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Электронный компонент: S-8460B00AFT-TB

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Rev.1.1
_00
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE
SWITCHING REGULATOR CONTROLLER
S-8460
Seiko Instruments Inc.
1
The S-8460 is a PWM control step-up and step-down
switching regulator-controller consisting of an
automatic-selection control circuit for step-up and
step-down, a reference voltage source, an oscillation
circuit, an error amplifier, a phase compensation
CMOS circuit, etc. The automatic-selection control
circuit for step-up and step-down in PWM control
realizes a high performance step-up and step-down
switching regulator operating on one coil. Adopting N-
channel power MOS transistors for external switches,
in addition, enables high efficiency and high output
current.
The S-8460 provides low-ripple output, high-efficiency
and excellent transient characteristics which come
from the PWM control circuit capable of varying the
duty ratio linearly from 0%, the optimized error
amplifier and the phase compensation circuit.
Features
High-efficiency is achieved from one coil by automatic-selection control circuit.
N-channel power MOS configuration for external switches realizes high-efficiency.
Synchronous rectification at step-down operation
Input voltage :
2.2 V to 18.0 V
Variable output voltage
:
Output voltage range 2.5 V to 6.0 V
Automatic-recovery overload protection circuit
Oscillation frequency :
300 kHz
Soft-start function set by an external capacitor Css
Power-off function
Applications
Power source for portable devices such as PDAs, electronic organizers, cellular phones.
Main or local power source for notebook PCs and peripherals.
Constant voltage source for cameras, video equipment and communication devices.
Available from 2 dry battery cells and 1 lithium cell to AC adapter.
Package
16-Pin TSSOP
(Package drawing code:
FT016-A
)
Product code
Product code
S-8460B00AFT-TB
Delivery form
Taping only
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
2
Seiko Instruments Inc.
Block Diagram
FB
EXT3
R
FB2
R
FB1
SD1
PWM automatic-
selection circuit
S-8460
C
BST
SD2
T
VSS DVSS
C
VL
C
PRO
CPRO
C
SS
CSS
VL
EXT2
LX
SW3
SW2
SW1
L
VIN
BST
EXT1
V
IN
C
IN
+
-
ON / OFF
Voltage
source
Osccilation
circuit
Overload
protection
Reference voltage
with soft-start
Cfzfb
C
OUT

Remark Diodes shown in the figure are parasitic diodes.
Figure 1
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
3
Pin Configuration
Table 1
Pin No.
Name
Description
1
VIN
IC Power supply pin
2 VL
Power supply for boost
*1
3
ON/ OFF Power-off pin
"H" : Normal operation (Step-up and -down)
"L" : Halt (No step-up and -down)
4 VSS
GND pin
*2
5
CSS
Capacitor connection for soft-start time
6
CPRO
Capacitor connection for protection time
7
T
Test pin, should be connected to GND
8 NC
No connection
*3
9 FB
FB
pin
10 NC
No connection
*3
11
EXT3
External transistor driving pin 3
12 DVSS
Digital GND pin
*2

3
4
14
2
13
1
15
16-Pin TSSOP
Top View
16
7
8
6
5
10
9
11
12
13
EXT2
External transistor driving pin 2
14
LX
Connection pin for coil
Figure 2
15
EXT1
External transistor driving pin 1
16
BST
Boost capacitor connection for SW1 driving
*1. No use except boosting this IC is allowed.
*2. VSS pin and DVSS pin are internally short-circuited.
*3. NC pin is electrically open. Connection of this pin to VIN or VSS is
allowed.
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
4
Seiko Instruments Inc.
Absolute Maximum Ratings
Table 2
(Ta=25C unless otherwise specified)
Parameter Symbol Ratings Unit
VIN pin voltage
V
IN
V
SS
-0.3 to V
SS
+20 V
FB pin voltage
V
FB
V
SS
-0.3 to V
SS
+20 V
ON/ OFF pin voltage
V
ON/
OFF
V
SS
-0.3 to V
SS
+20 V
CSS pin voltage
V
CSS
V
SS
-0.3 to V
L
+0.3 V
CPRO pin voltage
V
PRO
V
SS
-0.3 to V
L
+0.3 V
BST pin voltage
V
BST
V
SS
-0.3 to V
SS
+25 V
BST pin
LX pin voltage
V
BST
V
LX
-0.3 to +7 V
LX pin voltage
V
LX
V
SS
-3 to V
SS
+20 V
EXT1 pin voltage
V
EXT1
V
Lx
-0.3 to V
BST
+0.3 V
EXT2,3 pin voltage
V
EXT2,3
V
SS
-0.3 to V
L
+0.3 V
EXT1,2,3 pin current
I
EXT1,2,3
100 mA
LX pin current
I
LX
100 mA
BST pin current
I
BST
100 mA
VL pin voltage
*1
V
L
V
SS
-0.3 to V
SS
+7 V
VL pin current
*1
I
VL
100 mA
T pin voltage
*2
V
T
V
SS
-0.3 to V
SS
+20 V
Power dissipation
P
D
400
mW
Operating temperature rage
T
opr
-40 to + 85
C
Storage temperature range
T
stg
-40 to + 125
C
Caution The absolute maximum ratings are rated values exceeding which the product
could suffer physical damage. These values must therefore not be exceeded
under any conditions.
*1. Only capacitor C
VL
and Schottky diode D2 can be connected to this pin.
*2. T pin should be connected to GND.
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
5
Electrical Characteristics
Table 3
(Unless otherwise specified : V
IN
=5.0 V, I
OUT
=66 mA, output voltage is set to 3.3 V, Ta=25C)
Parameter Symbol
Conditions
Min.
Typ.
Max.
Unit
Test
Circuit
Output voltage at step-
down
V
OUTD
V
IN
=4.95
V
3.234 3.3 3.366 V 2
Output voltage at step-up
V
OUTU
V
IN
=2.64
V
3.234 3.3 3.366 V 2
Input voltage
V
IN
2.2
18.0 V 2
Current consumption 1
I
SS1
No external parts, V
OUT
=3.3 V0.95 V (Step-up
mode at MaxDuty)
900
1380
A 1
Current consumption 2
I
SS2
No external parts, V
OUT
=3.3 V+0.5 V(Step-down
mode at 0
% Duty)
75 150
A 1
Current consumption at
power-off
I
SSS
V
ON/
OFF
=0 V
0.5 2.0
A 1
VL pin output voltage
V
L
The same condition as I
SS2
4.32
4.50
4.68
V
1
I
EXT1,2,3H
V
VL
=4.5 V,
V
EXT1,2,3
= V
VL
-0.2 30
40
mA 1
EXT1,2,3pin output
current
I
EXT1,2,3L
V
EXT1,2,3
= 0.2 V
40
60
mA 1
Line regulation
V
OUT1
V
IN
= 2.2 V to 18.0 V
V
OUTD
1.0%
V
OUTD
2.0%
V 2
Load regulation
V
OUT2
I
OUT
= 10 A to 1.25 66 mA
V
IN
=4.95 V
V
OUTD
1.0%
V
OUTD
2.0%
V 2
Temperature coefficient
for output voltage
V
OUT
Ta V
OUT
Ta
=-40C to + 85C
100
ppm/C
Oscillation frequency
fosc
The same condition as I
SS1
, judged by wave form
at EXT3 pin.
255 300 345
kHz 1
Maximum duty
MaxDuty
The same condition as I
SS1
, judged by wave form
at EXT3 pin.
70 78 85
% 1
FB pin input current
I
FB
The same condition as I
SS2
0.0 0.1
A 1
ON/
OFF
pin
V
SH
The same condition as I
SS2
, judged by voltage
output at VL pin.
1.6
V 1
input voltage
V
SL
The same condition as I
SS2
, judged by voltage
output at VL pin.
0.4 V 1
ON/
OFF
pin
I
SH
The same condition as I
SS1
, V
ON/
OFF
=V
IN
-0.1
0.1 A 1
input leak current
I
SL
The same condition as I
SS1
, V
ON/
OFF
=0 V
-0.1
0.1 A 1
Soft-start time
T
SS
The same condition as I
SS1
, time for EXT3 pin to
start is measured.
6.0 12.0 24.0
ms 1
Integration time of
protection circuit
T
PRO
The same condition as I
SS1
, CSS pin: OPEN,
C
PRO
:2200 pF, repeat time of CPRO pin is
measured.
1.25 2.5 5.0 ms 1
Efficiency at step-down
EFFI1
V
IN
=4.95 V, I
OUT
=200 mA to 600 mA
87
% 2
Efficiency at step-up
EFFI2
V
IN
=2.64 V, I
OUT
=50 mA to 400 mA
83
% 2
Details for external parts
Coil:
Sumida Corporation
CDRH104R (22
H)
Diode: Panasonic
MA2Q737
(Schottky)
Rohm
Corporation
RB411D
(Schottky)
Capacitor:
Nichicon Corporation
F93 (16 V, 47
F, tantalum)4
Transistor:
Fairchild Semiconductor Corporation FDN337N
3
C
VL
:
4.7
F (Ceramic)
C
SS
: 4700
pF
C
PRO
: 2200
pF
C
BST
: 0.1
F
R
FB1
: 230 k
, R
FB2
: 100 k
, Cfzfb: 330 pF
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
6
Seiko Instruments Inc.
Test Circuits
1.
LX
VSS DVSS
CPRO
CSS
T
47
F
0.1
F
4700pF
2200pF
4.7
F
ON/OFF
VL
BST
FB
EXT1
EXT2
EXT3
VIN
A
A
A
A
A
A
2.
I
OUT
F93
47
F
A
VL
VSS DVSS
CPRO CSS
T
0.1
F
4.7
F
4700 pF
ON/OFF
EXT2
LX
EXT1
BST
FB
EXT3
VIN
CDRH104R
22
H
100 k
230 k
330 pF
RB411D
MA2Q737
FDN337N
FDN337N
FDN337N
F93
47
F
F93
47
F
F93
47
F
+
+
+
+
Figure 3
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
7
Operation
1. Step-up-and-down DC-DC converter
1.1 Basic
operation
The S-8460 automatically selects step-up operation or step-down operation to hold the output voltage
constant according to input voltage V
IN
, output voltage V
OUT
and output current I
OUT
. A high-efficient
power supply can be constructed using the S-8460, since the S-8460 works as a switching regurator for
both step-up and step-down operation.
Figure 4 shows the block diagram of the S-8460. Internal circuits operate on the voltage V
L
generated internally except pre-driver circuit for EXT1 and ON/ OFF circuit. When the input voltage V
IN
is 4.5 V or more, the voltage is down converted to 4.5 V to generate the internal voltage V
L
, and when
V
IN
is lower than 4.5 V, the internal voltage is set to V
IN
. The output voltage of the pre-driver circuit for
EXT1 lies between the BST pin voltage V
BST
and the LX pin voltage V
LX
where the BST pin voltage V
BST
is normally V
LX
plus V
L
. The gate to source voltages for all external power MOS transistors, SW1 to
SW3, thus become V
L
, which drives these external power MOS transistors.
FB
EXT3
PWM step-up and
step-down selection
VSS DVSS CPRO CSS
VL
EXT2
LX
VIN
BST
EXT1
+
-
ON / OFF
Voltage
source
Oscillation circuit
Overload
protection
Voltage refference
with soft-start
Figure 4
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
8
Seiko Instruments Inc.
1.2 Step-up operation
SW2
LX1
SW1
C
OUT
V
OUT
Parasitic diode
SD1
V
IN
SW3
ON/OFF
Figure 5
Step-up operation is carried out by setting SW1:ON, SW2:OFF, and toggling the SW3. The voltage
V
IN
+V
L
is needed at the BST pin to turn the SW1 on to maintain this state. For this purpose the
capacitor C
BST
is charged to V
L
by the switch combination SW1:OFF, SW2:ON for approximate 200 ns
just after the SW3 is turned off, and the BST pin is then bootstrapped to V
IN
+V
L
by SW1:ON, SW2:OFF.
The SW2 is turned on after the SW1 is turned off and the SW1 is turned on after the SW2 is turned
off to avoid the large current to flow between V
IN
and V
SS
if the SW1 and the SW2 are turned on
simultaneously. When the two switches, SW1 and SW2, are turned off, current flows to V
OUT
through
the parasitic diode of the SW2. In some MOS transistors current is not allowed to flow through the
parasitic diode. Then a Schottky diode must be connected parallel to the MOS transistor.
1.3 Step-down operation
SW2
ON/OFF
SW1 ON/OFF
C
OUT
V
OUT
SD1
V
IN
SW3
OFF
Parasitic diode
Figure 6
Step-down operation is carried out by synchronous switching of SW1 and SW2, and keeping SW3
open. The BST pin voltage is kept at V
IN
+V
L
, since the switches, SW1 and SW2, repeat toggling in each
period in step-down operation.
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
9
1.4 Control sequence
SW2
SW1
C
OUT
V
OUT
SD1
V
IN
SW3
Parasitic diode
Figure 7
If the switches, SW1 and SW2, are turned on simultaneously, V
IN
and V
SS
are short-circuited and
large useless current flows. And if the switches, SW2 and SW3, are turned on simultaneously, the
energy stored in the coil flows to V
SS
and is wasted. The S-8460 thus controls the switches in such a
way that in operations involving SW1 and SW2, and involving SW2 and SW3 both transistors are turned
off simultaneously to avoid useless current flowing due to simultaneous turn-on of the switches.
1.5 Step-up and step-down selection control
The S-8460 automatically selects operation between step-up and step-down to maintain a constant
output voltage according to the relation which holds among input voltage V
IN
, output voltage V
OUT
and
output current I
OUT
. Simple relations that step-up operation works when input voltage
output voltage
and that step-down operation works when input voltage
output voltage do not hold. Step-up operation
emerges when the output voltage is kept constant by step-up operation, and step-down operation
emerges when the output voltage is kept constant by step-down operation according to the relation
among input voltage V
IN
, output voltage V
OUT
and output current I
OUT
.
Figure 8 shows the turning point between step-up operation and step-down schematically for the
case when the output voltage is 3.3 V. In the area where the two slant lines are crossing and noted by
"Step-up and -down" the S-8460 shows step-up operation or step-down operation. Not that step-up
operation and step-down operation appear alternately in this area, but that one of the two operations is
selected and stable operation is carried out. The voltage for the turning point between step-up and
step-down varies slightly due to external parts and mounting conditions.
Step-down operation
18
3.3
2.2
0.1
1.0
10.0
100.0
1000.0
I
OUT
(mA)
V
IN
(V)
Output voltage
Step-up or -down
Step-up operation
Figure 8 Graphic scheme for automatic selection of step-up and step-down for V
OUT
=
=
=
=3.3 V
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
10
Seiko Instruments Inc.
1.6 PWM control
The S-8460 is a pulse width modulation (PWM) control DC/DC converters. In conventional pulse
frequency modulation (PFM) DC/DC converters, pulses are skipped when the convertors operate at
light load, and caused variation in the ripple frequency and increase in the ripple voltage of the output
both of which constitute inherent drawbacks to those converters.
In the S-8460 the pulse width varies in the range from 0 to 100
% in step-down operation and 0 to 78%
in step-up according to the load, yet ripple voltage produced by the switching can easily be removed by
a filter since the switching frequency is always constant. The converter thus provides a low-ripple
voltage over wide range of input voltage and load current.
2. Internal circuits
ON/ OFF pin (Power-off pin)
When the ON/ OFF pin is set to "L", the EXT1 pin voltage becomes eqaul to the L
X
voltage and the
pin voltage of the EXT2 and EXT3 becomes V
SS
level to turn the power MOS transistors off as well as
the S-8460 stops all the internal circuit and suppresses the current consumption down to 0.5
A
approximately. At the same time the internal voltage, the CSS pin and CPRO pin become V
SS
level.
Electrical isolation between power input side V
IN
and output side V
OUT
is thus possible when the S-
8460 is in halt state.
The ON/ OFF pin is constructed as shown in the Figure 9. Since pull-up or pull-down is not
performed internally, operation where the ON/ OFF pin is in a floating state should be avoided. When
the ON/ OFF pin is not used, it should be connected to the VIN pin.

3. Soft-start function
The S-8460 has a built-in soft-start circuit. This circuit enables the output voltage to rise gradually
over the specified soft-start time to suppress the overshooting of the output voltage and the rush current
from the power source when the power is switched on or the ON/ OFF pin is set to "H".
The soft-start time T
SS
is determined by an external capacitor C
SS
. The time needed for V
OUT
to reach
95
% of the setting value of the output volltage is approximately expressed by the following equatuion.
T
SS
(ms)=0.0026
C
SS
(pF)
ON/OFF
VIN
VSS
ON/ OFF
pin
CR oscillation
circuit
All EXT pin
voltage
Output
voltage
"H" Active
Set value
"L" Non-active V
SS
Open
Figure 9
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
11
Soft-start time
0
10
20
30
40
50
60
70
80
90
100
0
5000
10000
15000
20000
External capacity
C
SS
(pF)
Soft-start
time (
ms)
Figure 10
The value for C
SS
should be selected to give enough margin to the soft-start time against the power
supply rise time. If the soft-start time is short, possibilty for output overshoot, input current rush and
malfunction of the IC increases.
4. Overload protection Circuit
The S-8460 contains a built-in overload protection circuit. When the output voltage falls because of
an overload despite the step-up operation or step-down, the S-8460 enters the step-up operation and
holds the maximum duty step-up operation. If this maximum duty state lasts longer than the overload
detection time T
PRO
, the overload protection circuit will hold the pins EXT1 to EXT3 at "L" to protect the
switching transistors and the inductor. When the overload protection circuit works, the output voltage
rises slowly since a soft-start is carried out in the reference voltage circuit in the IC to rise the reference
voltage slowly from 0 V. If the load is still heavy at this time and the maximum duty step-up operation
lasts longer than the overload detection time T
PRO
, the overload protection circuit will work again.
Repeat of this process leads to an operation of intermittent mode. If the overload is removed, the S-
8460 goes back to the normal operation.
The overload detection time T
PRO
which is measured from the beginning of the maximum duty
operation to the instant at which pin voltage of the EXT1 to EXT3 is held "L" to protect switching
transistors and the inductor is determined by the external capacitor C
PRO
, and is expressed by the
following equation.
T
PRO
(ms)=0.0011
C
PRO
(pF)
Selection of Extarnal parts
1. Inductor
The inductance value greatly affects the maximum output current I
OUT
and the efficiency
.
As the Inductance is reduced gradually, the peak current I
PK
increases, and the output current I
OUT
reaches the maximum at a certain Inductance value. As the Inductance is made even smaller, I
OUT
begins to decrease since the current drivability of the switching transistor becomes insufficient.
Conversely, as the Inductance is increased, the loss in the switching transistor due to I
PK
decreases,
and the efficiency reaches the maximum at a certain Inductance value. As the Inductance is made
even larger, the efficiency degrades since the loss due to the series resistance of the inductor
increases. In many applications, an inductance of 22
H will yield the best characteristics of the S-8460
in a well balanced manner.
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
12
Seiko Instruments Inc.
When choosing an inductor, attention to its allowable current should be paid since the current over
the allowable value will cause magnetic saturation in the inductor, leading to a marked decline in
efficiency.
An inductor should therefore be selected so as not the peak current I
PK
to surpass its allowable
current. The peak current I
PK
is represented by the following equations in step-up operation and in step-
down operation. Comparing each calculation result for step-up and step-down, larger value should be
taken as the I
PK
. Adding some margin to the obtained result, an inductor with the allowable current can
be thus chosen.
Continuous mode at step-up operation
I
V
V
V
I
(V
V
V ) V
2 (V
V ) fosc L
PK
OUT
F
IN
OUT
OUT
F
IN
IN
OUT
F
=
+
+
+
-
+
Continuous mode at step-down operation
I
I
V
(V
V
)
2 fosc L V
PK
OUT
OUT
IN
OUT
IN
=
+
-
Where fosc (
=300 kHz) is the oscillation frequency, L is the inductance of the inductor, and V
F
is the
diode forward voltage (
0.4 V).
2. Capacitors
2.1 Input and output capacitors (C
IN
, C
OUT
)
A capacitor inserted in the input side (C
IN
) serves to reduce the power impedance and to average the
input current to give better efficiency. The capacitor should have low ESR (Equivalent Series
Resistance) and large capacitance which should be selected according to the impedance of the power
supply. It should be 47 to 100
F, although the actual value depends on the impedance of the power
source used and load current value.
For the output side capacitor (C
OUT
), select a large capacitance with low ESR (Equivalent Series
Resistance) to smoothen the ripple voltage. When the input voltage is extremely high or the load
current is extremely large, the output voltage may become unstable. In this case the unstable area will
become narrow by selecting a large capacitance for an output capacitor. A tantalum electrolyte
capacitor is recommended since the unstable area widens when a capacitor with a large ESR, such as
an aluminum electrolyte capacitor, or a capacitor with a small ESR, such as a ceramic capacitor, is
chosen.
In selecting input and output capacitors sufficient evaluation is needed in actual application
environment.
2.2 Internal power source stabilization capacitor (C
VL
)
The main circuits of the IC work on an internal power source connected to the VL pin. The C
VL
is a
bypass capacitor for stabilizing the internal power source. C
VL
is a 4.7
F ceramic capacitor and should
be wired in a short distance and at a low impedance.
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
13
3. External Switching Transistors
Enhancement N-channel MOS FETs are recommended to use with the S-8460 for the extarnal
switching transistors. The SW1 is drived by the bootstrapped voltage. If a bipolar transistor is used for
the SW1, the transisitor does not turn on since the charge in the capacitor C
BST
for bootstrap is
discharged.
3.1 Enhancement MOS FET
The gate driving pins EXT1 to EXT3 of the S-8460 can directly drive an N-cannel power MOS FET
with a gate capacitance of approximate 1000 pF.
When an N-channel power MOS FET is chosen, efficiency will be 2 to 3
% higher than that achieved
by a PNP or an NPN bipolar transistor since the MOS FET switching speed is faster than that of the
bipolar transistor and power loss due to the base current is avoided.
The important parameters in selecting an N-channel power MOS FET are threshold voltage,
breakdown voltage between gate and source, breakdown voltage between drain and source, total gate
capacitance, on-resistance, and the current rating.
Voltage swing of the EXT2 and EXT3 is between VL and VSS. The EXT1 pin voltage swings
between V
L
and V
SS
since the LX pin voltage becomes V
SS
when the SW2 is on and swings between
V
L
+V
IN
and VIN since the LX pin voltage becomes V
IN
when the SW2 is off. The gate to source
breakdown voltage of the transistors should be at least some volts higher than VL voltage since the
maximum voltage applied between gate and source of each transistor is V
L
. On the other hand when
the input voltage V
IN
is lower than 4.5 V, the threshold voltage of MOS FETs should be low enough to
turn on completely at low input voltage since the V
L
voltage becomes V
IN
voltage.
Immediately after the power is turned on, or the power-off state at which the step-up and -down
operation is terminated, the input voltage or output voltage is applied across the drain and the source of
the MOS FETs. The transistors therefore need to have drain to source breakdown voltage that is also
several volts higher than the input voltage or output voltage.
The total gate capacitance and the on-resistance affect the efficiency.
The larger the total gate capacitance becomes and the higher the input voltage becomes, the more
the power loss for charging and discharging the gate capacitance by switching operation increases, and
affects the efficiency at low load current region. If the efficiency at low load is important, select MOS
FETs with a small total gate capacitance.
In regions where the load current is high, the efficiency is affected by power loss caused by the on-
resistance of the MOS FETs. If the efficiency under heavy load is particularly important in the
application, choose MOS FETs having on-resistance as low as possible.
As for the current rating, select a MOS FET whose maximum continuous drain current rating is higher
than the peak current I
PK
.
If the external N-channel MOS FETs have much different characteristics (input capacitance, Vth, etc.)
among them, they turn on at the same time to let a short-circuit current flow and reduce efficiency. If a
MOS FET with a large input capacitance is used, switching loss increases and efficiency decreases. If
such a MOS FET is used at several hundreds of mA or more, the loss at the MOS FET increases and
may exceed the power dissipation of the MOS FET. In selecting N-channel MOS FETs, enough
performance evaluation under the actual condition is indispensable.
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
14
Seiko Instruments Inc.
For reference, efficiency data using Sanyo CPH6401, CPH3403 and FTS2001, Siliconix Si2302DS,
and Fairchild FDN335N is attatched in this document. Please see "Reference Data".
In some MOS FETs current flow through the parasitic diode is not allowed . In this case, a Schottky
diode must be connected in parallel to the MOS FET. The Schottky diode must have a low forward
voltage, a high switching speed, a reverse-direction withstand voltage higher than the input/output
voltage, and a current rating higher than I
PK
.
4. Output voltage adjustment
The output voltage can be set and adjusted in the output voltage setting range (2.5 to 6.0 V) by
adding external resistors R
FB1
and R
FB2
and a capacitor Cfzfb in the S-8460. Temperature gradient can
be added by inserting a thermistor in series to R
FB1
and R
FB2
.
The output voltage is set as (R
FB1
+R
FB2
)/R
FB2
, since the FB pin voltage is kept 1.0 V. R
FB1
+R
FB2
must
be smaller than 2 M
. A capacitor Cfzfb should be added in parallel to the resistor R
FB1
to avoid
unstable operation like output oscillation.
Set the Cfzfb so that f
= 1/(2 Cfzfb R
FB1
) is equal to 2 kHz.
Example: When V
OUT
=3.3 V, R
FB1
=200 k, R
FB2
=100 k, then Cfzfb=330 pF is recommended.
The precision of output voltage V
OUT
determined by the resistors R
FB1
and R
FB2
is affected by the
precision of the voltage at the FB pin (1 V
2.0%) as well as the precision of external resistors R
FB1
and
R
FB2
, and IC power supply voltage V
IN
.
Waste current flows through external resistors R
FB1
and R
FB2
. When it is not a negligible value with
respect to load current in actual use, the efficiency decreases. The values of the external resistors must
therefore be made large.
When the R
FB1
and R
FB2
values are high, 1 M
or higher, evaluation of the influence of the noise is
needed in the actual condition since the resistors become susceptible to external noise.
5. Diode
Diode should meet the following requirements:
The forward voltage is low (Schottky barrier diode is recommended).
The switching speed is high (50 ns).
The current rating is larger than I
PK
The reverse breakdown voltage is higher than V
IN
or V
OUT
for SD1.
The reverse breakdown voltage is higher than V
IN
for SD2.2.
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
15
Standard Circuit
N-channel MOS FETs are used for SW1 to SW3
VL
VSS DVSS
CPRO
CSS
T
C
BST
C
VL
4.7
F
C
PRO
C
SS
ON/OFF
EXT2
LX
EXT1
BST
FB
EXT
VIN
A
L
I
OUT
SD2
R
FB2
R
FB1
Cfzfb
SD1
SW3
SW1
SW2
C
IN
C
OUT
+
+
+
+
Caution The above connections and values will not guarantee correct operation. Before setting
these values, perform sufficient evaluation on the application to be actually used.
Figure 11
Precautions
Install the external capacitors, diode, coil, and other peripheral components as close to the IC as
possible, and make a one-point grounding.
Normally the SW1 and SW2 do not turn on at the same time. If external N-channel MOS FETs have
much different characteristics (input capacitance, Vth, etc.) among them, however, they may turn on at
the same time, and short-circuit current flows. Select transistors with similar characteristics.
Characteristics ripple voltage and spike noise occur in IC containing switching regulators. Moreover
rush current flows at the time of a power supply injection. Because these largely depend on the coil, the
capacitor and inpedance of power supply used, fully check them using an actually mounted model.
When the input voltage is high and the output current is low, pulses with a low duty ratio may appear,
and then the 0
% duty ratio continues for several clocks. In this case the operation changes to the
pseudo pulse frequency modulation (PFM) mode, but the ripple voltage hardly increases.
According to the input voltage and the load condition the oscillation frequency of the EXT1 to EXT3
may become an integer fraction of 300 kHz.
No parts other than a capacitor C
VL
and a schottky diode SD2 can be connected to the VL pin.
A 4.7-F ceramic capacitor should be connected to the VL pin.
The overload protection circuit of the IC starts working by detecting the time for maximum duty. In
choosing the components, make sure that the overcurrent caused by load short-circuiting will not
exceed the power dissipation of the switching transistors, diodes, and the inductor.
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
16
Seiko Instruments Inc.
The oscillation frequency of the EXT1 and EXT2 may vary in some voltage range and load condition
depending on input voltage.
If the VOUT pin is short-circuited to VSS, the protection circuit starts to operate before the integral
protection time T
PRO
passes.
When the temperature is high and the load is 0 to about 1A, the voltage of the EXT1 to EXT3 pins is
held "L" and the output voltage VOUT increases. The operation returns to normal when the load of
1
A or more is attached.
Make sure that dissipation of the switching transistor especially at high temperature will not surpass the
power dissipation of the package.
Do not apply an electrostatic discharge to this IC that exceeds the performance ratings of the built-in
electrostatic protection circuit.
Seiko Instruments Inc. shall bear no responsibility for any patent infringement by a product that
includes an IC manufactured by Seiko Instruments Inc. in relation to the method of using the IC in that
product, the product specifications, or the destination country.
Package Power Dissipation
0
300
500
400
100
200
0
50
100
150
P
D
(mW)
Ambient Temperature Ta (C)
Power
Dissipation
Figure 12 16-Pin TSSOP package power dissipation in free air
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
17
Typical Characteristeics of Major Parameters
(1)I
SS2
V
IN
(2)I
SS1
V
IN
0
20
40
60
80
100
120
140
2
4
6
8
10
12
14
16
18
V
IN
(V)
I
SS2
(
A)
Ta=-40
C
25
C
85
C
0
200
400
600
800
1000
2
4
6
8
10
12
14
16
18
V
IN
(V)
I
SS1
(
A)
Ta=-40
C
25
C
85
C
(3)I
SSS
V
IN
(4)V
L
V
IN
0.0
0.5
1.0
1.5
2.0
2.5
3.0
2
4
6
8
10
12
14
16
18
V
IN
(V)
I
SSS
(
A)
Ta=-40
C
25
C
85
C
0
1
2
3
4
5
6
2
4
6
8
10
12
14
16
18
V
IN
(V)
V
L
(V)
Ta=-40
C 25C
85
C
(5)V
SH
V
IN
(6)V
SL
V
IN
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2
4
6
8
10
12
14
16
18
V
IN
(V)
V
SL
(V)
Ta=-40
C
25
C
85
C
0.0
0.2
0.4
0.6
0.8
1.0
1.2
1.4
1.6
1.8
2.0
2
4
6
8
10
12
14
16
18
V
IN
(V)
V
SH
(V)
Ta=-40
C
25
C
85
C
(7)Fosc
V
IN
(8)Max.Duty
V
IN
250
270
290
310
330
350
2
4
6
8
10
12
14
16
18
V
IN
(V)
Fosc (kHz)
Ta=-40
C
25
C
85
C
70
72
74
76
78
80
82
84
2
4
6
8
10
12
14
16
18
V
IN
(V)
Max.Duty (%)
Ta=-40
C
25
C
85
C
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
18
Seiko Instruments Inc.
(9)I
EXTH1H
V
IN
(10)I
EXT1L
V
IN
0
20
40
60
80
100
2
4
6
8
10
12
14
16
18
V
IN
(V)
I
EXT1H
(mA)
Ta=-40
C
25
C
85
C
0
20
40
60
80
100
120
140
2
4
6
8
10
12
14
16
18
V
IN
(V)
I
EXT1L
(mA)
Ta=-40
C
25
C
85
C
(11)I
EXTH2H
V
IN
(12)I
EXT2L
V
IN
0
20
40
60
80
100
2
4
6
8
10
12
14
16
18
V
IN
(V)
I
EXT2H
(mA)
Ta=-40
C
25
C
85
C
0
20
40
60
80
100
120
140
2
4
6
8
10
12
14
16
18
V
IN
(V)
I
EXT2L
(mA)
Ta=-40
C
25
C
85
C
(13)I
EXTH3H
V
IN
(14)I
EXT3L
V
IN
0
20
40
60
80
100
2
4
6
8
10
12
14
16
18
V
IN
(V)
I
EXT3H
(mA)
Ta=-40
C
25
C
85
C
0
20
40
60
80
100
120
140
2
4
6
8
10
12
14
16
18
V
IN
(V)
I
EXT3L
(mA)
Ta=-40
C
25
C
85
C
(15)T
SS
V
IN
(16)T
PRO
V
IN
0
5
10
15
20
25
30
2
4
6
8
10
12
14
16
18
V
IN
(V)
T
SS
(ms)
C
SS
:4700pF
Ta=-40
C
25
C
85
C
0
1
2
3
4
5
6
7
8
2
4
6
8
10
12
14
16
18
V
IN
(V)
T
PRO
(ms)
C
PRO
:2200pF
Ta=-40
C
25
C
85
C
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
19
Typical Characteristics for Transient Response
1. Response to power on (V
IN
: 0V
2.64V or 4.95 V or 18.0 V I
OUT
: no load) V
OUT
: 3.3 V, C
SS
: 4700 pF
(1) S-8460B00AFT
(2) S-8460B00AFT
TIME(2ms/div)
0V
4V
0V
3V
V
IN
(1V/div)
Output
voltage
(1V/div)
V
IN
:0V
2.64V
TIME(2ms/div)
0V
5V
0V
3V
V
IN
(1V/div)
Output
voltage
(1V/div)
V
IN
:0V
4.95V
(3) S-8460B00AFT
TIME(2ms/div)
0V
20V
0V
3V
V
IN
(4V/div)
Output
voltage
(1V/div)
V
IN
:0V
18V
2. Responce to power -off pin (V
ON/
OFF
: 0 V
2.2 V I
OUT
: no load) V
OUT
: 3.3 V, C
SS
: 4700 pF
(1) S-8460B00AFT
(2) S-8460B00AFT
TIME(2ms/div)
V
IN
:2.64V
0V
3V
0V
3V
Output
voltage
(1V/div)
V
(1V/div)
ON/OFF
TIME(2ms/div)
V
IN
:4.95V
0V
3V
0V
3V
Output
voltage
(1V/div)
V
(1V/div)
ON/OFF
(3) S-8460B00AFT
TIME(2ms/div)
V
IN
:18.0V
0V
3V
0V
3V
Output
voltage
(1V/div)
V
(1V/div)
ON/OFF
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
20
Seiko Instruments Inc.
3. Response to power voltage shift
(V
IN
: 2.7 V
5.0 V,5.0 V 2.7 V,2.2 V 18.0 V 2.2 V I
OUT
: 100 mA) V
OUT
: 3.3 V
(1) S-8460B00AFT
(2) S-8460B00AFT
TIME(0.5ms/div)
V
IN
:2.7V
5.0V I
OUT
:100mA
5V
0V
Input
voltage
(1.0V/div)
Output
voltage
(0.1V/div)
TIME(0.5ms/div)
V
IN
:5.0V
2.7V I
OUT
:100mA
5V
0V
Input
voltage
(1.0V/div)
Output
voltage
(0.1V/div)
(3) S-8460B00AFT
(4) S-8460B00AFT
TIME(0.5ms/div)
V
IN
:2.2V
18.0V I
OUT
:100mA
20V
0V
Input
voltage
(4.0V/div)
Output
voltage
(0.1V/div)
TIME(0.5ms/div)
V
IN
:18.0V
2.2V I
OUT
:100mA
20V
0V
Input
voltage
(4.0V/div)
Output
voltage
(0.1V/div)
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
21
4. Response to load shift (I
OUT
: 10
A 100 mA, 100 mA 10 A, V
IN
: 2.64 V, 4.95 V, 18.0 V) V
OUT
: 3.3V
(1) S-8460B00AFT
(2) S-8460B00AFT
TIME(0.5ms/div)
I
OUT
:10
A100mA V
IN
:2.64V
100mA
Output
current
10
A
Output
voltage
(0.1V/div)
TIME(40ms/div)
I
OUT
:100mA
10A V
IN
:2.64V
100mA
Output
current
10
A
Output
voltage
(0.1V/div)
(3) S-8460B00AFT
(4) S-8460B00AFT
TIME(0.5ms/div)
I
OUT
:10
A100mA V
IN
:4.95V
100mA
Output
current
10
A
Output
voltage
(0.1V/div)
TIME(40ms/div)
I
OUT
:100mA
10A V
IN
:4.95V
100mA
Output
current
10
A
Output
voltage
(0.1V/div)
(5) S-8460B00AFT
(6) S-8460B00AFT
TIME(0.5ms/div)
I
OUT
:10
A100mA V
IN
:18.0V
100mA
Output
current
10
A
Outout
voltage
(0.1V/div)
TIME(40ms/div)
I
OUT
:100mA
10A V
IN
:18.0V
100mA
Output
current
10
A
Output
voltage
(0.1V/div)
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
22
Seiko Instruments Inc.
Reference data
Reference data are intended for use in selecting peripheral components to the IC. The information therefore
provides characteristic data in which external components are selected with a view of wide variety of IC
applications. All data shows typical value.
External components list for efficiency-output voltage, efficiency-input voltage, output voltage-
output current, and output voltage-input voltage characteristics
Table 4
No. Product
Name
Output
Voltage
Transistor Diode
Inductor
Output
Capacitor
Input
Capacitor
(1) S-8460B00AFT
3.3 V
*1
CPH6401 MA2Q737 CDRH104R/22 H 47
F2 47
F2, 0.1 F
(2)
FTS2001
(3)
CPH3403
(4)
D1FH3
(5)
Si2302DS
(6)
FDN335N
(7)
CPH6401 MA2Q737 CDRH104R/10 H
(8)
CDRH104R/47
H
(9)
2.5 V
*2
CDRH104R/22
H
(10)
CPH3403 D1FH3
(11)
CPH6401 MA2Q737 CDRH104R/10 H
(12)
CDRH104R/47
H
(13)
5.0 V
*2
CDRH104R/22
H
(14)
CPH3403 D1FH3
(15)
CPH6401 MA2Q737 CDRH104R/10 H
(16)
CDRH104R/47
H
(17)
3.3 V
*1
CDRH104R/22
H
(18)
FTS2001
(19)
CPH3403
(20)
D1FH3
(21)
Si2302DS
(22)
FDN335N
(23)
CPH6401 MA2Q737 CDRH104R/10 H
(24)
CDRH104R/47
H
(25),(28)
3.3 V
*1
CDRH104R/22
H
(26),(29)
2.5 V
*2
CDRH104R/22
H
(27),(30)
5.0 V
*2
CDRH104R/22
H
*1 External parts: R
FB1
=230 k
, R
FB2
=100 k
, Cfzfb=330 pF
*2 External parts: R
FB1
=150 k
, R
FB2
=100 k
, Cfzfb=470 pF
*3 External parts: R
FB1
=400 k
, R
FB2
=100 k
, Cfzfb=220 pF
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
23
Test circuit
VL
VSS DVSS
CPRO CSS
T
0.1
F
4700pF
4.7
F
ON/OFF
EXT2
LX
EXT1
BST
FB
EXT3
VIN
A
CDRH104R
22
H
I
OUT
R
FB2
100 k
R
FB1
230 k
Cfzfb
230pF
RB411D
MA2Q737
CPH6401
CPH6401
CPH6401
F93
47
F
F93
47
F
F93
47
F
F93
47
F
+
+
+
+
Remark Values for R
FB1
, R
FB2
, and Cfzfb differ
according to the ouput.
External components list for ripple data
Table 5
No. Product
Name Output
Voltage
Transistor
Nch
Diode
SD1
Inductor Output
Capacitor
Input
Capacitor
(31) S-8460B00AFT 3.3 V*
1
CPH6401 MA2Q737 CDRH104R/22 H 47
F2 47
F2, 0.1
F
(32)
CDRH104R/10
H
(33)
CDRH104R/47
H
(34)
2.5 V*
2
CDRH104R/22
H
(35)
5.0 V*
3
CDRH104R/22
H
*1. External parts: R
FB1
=230 k
, R
FB2
=100 k
, Cfzfb=330 pF
*2. External parts: R
FB1
=150 k
, R
FB2
=100 k
, Cfzfb=470 pF
*3. External parts: R
FB1
=400 k
, R
FB2
=100 k
, Cfzfb=220 pF
Performance data for components
Table 6
Component
Product
Name
Manufacturer Performance
L
DC
resist.
Max.
current
Diameter
Hight
47
H 0.095
2.1 A
Inductor CDRH104R
Sumida
Corporation
22
H 0.054
2.9 A
13.5 mm max.
4.0 mm max.
10
H 0.026
4.4 A
MA2Q737
Panasonic
Forward current 2.0 A @V
F
=0.5 V
Diode D1FH3
Shin
Dengen
Electric
Manufacturing
Co., Ltd.
Forward current 1.0 A @V
F
=0.3 V
Output Capacity
F93
Nichicon Corporation
CPH6401 Sanyo Electric Co., Ltd. V
GS
12 V max. , I
D
4 A max. , V
th
0.4 V min. , Ci
ss
300 pF typ.
R
on
0.105
max.(V
gs
=2.5 V) , CPH6
CPH3403 Sanyo Electric Co., Ltd. V
GS
12 V max. , I
D
2.2 A max. , V
th
0.4 V min. , C
iss
170 pF typ.
R
on
0.220
max.(V
gs
=2.5 V) , CPH3
External Transistor
(N-channel MOS FET)
FTS2001 Sanyo Electric Co., Ltd. V
GS
10 V max. , I
D
5A max. , V
th
0.4 V min. , C
iss
750 pF typ.
R
on
0.046
max.(V
gs
=2.5V) , TSSOP-8
Si2302DS
Vishay
Siliconix
V
GS
8 V max. , I
D
2.8 A max. , V
th
0.65 V min. ,
R
on
0.115
max.(V
gs
=2.5 V) , SOT-23
FDN335N
Fairchild
Semiconductor
Corporation
V
GS
8 V max. , I
D
1.7 A max. , V
th
0.4 V min. , C
iss
310 pF typ.
R
on
0.100
max.(V
gs
=2.5 V) , Super SOT-3
Super SOT-3 is a trademark of Fairchild Semiconductor Corporation.
Figure 13
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
24
Seiko Instruments Inc.
1.Effficiency



Output current I
OUT
characteristics
(1) S-8460B00AFT(V
OUT
=3.3 V)
(2) S-8460B00AFT(V
OUT
=3.3 V)
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH6401,MA2Q737,CDRH104R/22
H
V
IN
=2.7V
3.0V
4.95V
3.3V
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
FTS2001,MA2Q737,CDRH104R/22
H
V
IN
=2.7V
3.0V
3.3V
4.95V
(3) S-8460B00AFT(V
OUT
=3.3 V)
(4) S-8460B00AFT(V
OUT
=3.3 V)
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH3403,MA2Q737,CDRH104R/22
H
V
IN
=2.7V
3.0V
4.95V
3.3V
4.0V
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH3403,D1FH3,CDRH104R/22
H
V
IN
=2.7V
3.0V
4.95V
3.3V
4.0V
3.3V
(5) S-8460B00AFT(V
OUT
=3.3 V)
(6) S-8460B00AFT(V
OUT
=3.3 V)
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
Si2302DS,D1FH3,CDRH104R/22
H
V
IN
=2.7V
3.0V
4.95V
3.3V
4.0V
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
FDN335N,D1FH3,CDRH104R/22
H
V
IN
=2.7V
3.0V
4.95V
3.3V
4.0V
3.3V
(7) S-8460B00AFT(V
OUT
=3.3 V)
(8) S-8460B00AFT(V
OUT
=3.3 V)
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH6401,MA2Q737,CDRH104R/10
H
V
IN
=2.7V
3.0V
4.95V
3.3V
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH6401,MA2Q737,CDRH104R/47
H
V
IN
=2.7V
3.0V
4.95V
3.3V
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
25
(9) S-8460B00AFT(V
OUT
=2.5 V)
(10) S-8460B00AFT(V
OUT
=2.5 V)
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH6401,MA2Q737,CDRH104R/22H
V
IN
=2.2V
2.5V
3.75V
5.0V
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH3403,D1FH3,CDRH104R/22
H
V
IN
=2.2V
2.5V
3.75V
5.0V
3.0V
(11) S-8460B00AFT(V
OUT
=2.5 V)
(12) S-8460B00AFT(V
OUT
=2.5 V)
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH6401,MA2Q737,CDRH104R/10H
V
IN
=2.2V
2.5V
3.75V
5.0V
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH6401,MA2Q737,CDRH104R/47
H
V
IN
=2.2V
2.5V
3.75V
5.0V
(13) S-8460B00AFT(V
OUT
=5.0 V)
(14) S-8460B00AFT(V
OUT
=5.0 V)
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH6401,MA2Q737,CDRH104R/22H
V
IN
=3.0V
4.0V
7.5V
5.0V
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH3403,D1FH3,CDRH104R/22
H
V
IN
=3.0
4.0V
7.5V
5.0V
5.8V
(15) S-8460B00AFT(V
OUT
=2.5 V)
(16) S-8460B00AFT(V
OUT
=2.5 V)
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH6401,MA2Q737,CDRH104R/10H
V
IN
=3.0V
4.0V
7.5V
5.0V
50
60
70
80
90
100
1
10
100
1000
I
OUT
(mA)
efficiency
(%)
CPH6401,MA2Q737,CDRH104R/47
H
V
IN
=3.0V
4.0V
7.5V
5.0V
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
26
Seiko Instruments Inc.
2.Efficiency
Input voltage V
IN
characteristics
(17) S-8460B00AFT(V
OUT
=3.3 V)
(18) S-8460B00AFT(V
OUT
=3.3 V)
50
60
70
80
90
100
2
3
4
5
V
IN
(V)
efficiency
(%)
CPH6401,MA2Q737,CDRH104R/22H
100mA
I
OUT
=50mA
66mA
200mA
50
60
70
80
90
100
2
3
4
5
V
IN
(V)
efficiency
(%)
FTS2001,MA2Q737,CDRH104R/22H
100mA
I
OUT
=50mA
66mA
200mA
(19) S-8460B00AFT(V
OUT
=3.3 V)
(20) S-8460B00AFT(V
OUT
=3.3 V)
50
60
70
80
90
100
2
3
4
5
V
IN
(V)
efficiency
(%)
CPH3403,MA2Q737,CDRH104R/22H
100mA
I
OUT
=50mA
66mA
200mA
50
60
70
80
90
100
2
3
4
5
V
IN
(V)
efficiency
(%)
CPH3403,D1FH3,CDRH104R/22H
100mA
I
OUT
=50mA
66mA
200mA
(21) S-8460B00AFT(V
OUT
=3.3 V)
(22) S-8460B00AFT(V
OUT
=3.3 V)
50
60
70
80
90
100
2
3
4
5
V
IN
(V)
efficiency
(%)
Si2302DS,D1FH3,CDRH104R/22H
100mA
I
OUT
=50mA
66mA
200mA
50
60
70
80
90
100
2
3
4
5
V
IN
(V)
efficiency
(%)
FDN335N,D1FH3,CDRH104R/22H
100mA
I
OUT
=50mA
66mA
200mA
(23) S-8460B00AFT(V
OUT
=3.3 V)
(24) S-8460B00AFT(V
OUT
=3.3 V)
50
60
70
80
90
100
2
3
4
5
V
IN
(V)
efficiency
(%)
CPH6401,MA2Q737,CDRH104R/10H
100mA
I
OUT
=50mA
66mA
200mA
50
60
70
80
90
100
2
3
4
5
V
IN
(V)
efficiency
(%)
CPH6401,MA2Q737,CDRH104R/47H
100mA
I
OUT
=50mA
66mA
200mA
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
Rev.1.1
_00
S-8460
Seiko Instruments Inc.
27
3.Output voltage V
OUT
Output current I
OUT
characteristics
(25) S-8460B00AFT(V
OUT
=3.3 V)
3.15
3.20
3.25
3.30
3.35
3.40
3.45
1
10
100
1000
I
OUT
(mA)
V
OUT
(V)
CPH6401,MA2Q737,CDRH104R/22
H
2.7V
V
IN
=2.2V
3.3V
18V
4.95V
(26) S-8460B00AFT(V
OUT
=2.5 V)
(27) S-8460B00AFT(V
OUT
=5.0 V)
2.40
2.45
2.50
2.55
2.60
2.65
2.70
1
10
100
1000
I
OUT
(mA)
V
OUT
(V)
CPH6401,MA2Q737,CDRH104R/22
H
2.5V
V
IN
=2.2V
3.75V
18V
5V
4.95
5.00
5.05
5.10
5.15
5.20
5.25
1
10
100
1000
I
OUT
(mA)
V
OUT
(V)
CPH6401,MA2Q737,CDRH104R/22
H
4V
V
IN
=2.2V
5V
18V
7.5V
4.Output voltage
Input voltage characteristics
(28) S-8460B00AFT(V
OUT
=3.3 V)
3.25
3.27
3.29
3.31
3.33
3.35
2
3
4
5
V
IN
(V)
V
OUT
(V)
CPH6401,MA2Q737,CDRH104R/22
H
66mA
I
OUT
=0.1mA
100mA
200mA
(29) S-8460B00AFT(V
OUT
=2.5 V)
(30) S-8460B00AFT(V
OUT
=5.0 V)
2.48
2.50
2.52
2.54
2.56
2.58
2
3
4
5
V
IN
(V)
V
OUT
(V)
CPH6401,MA2Q737,CDRH104R/22
50mA
I
OUT
=0.1mA
100mA
200mA
5.00
5.02
5.04
5.06
5.08
5.10
2
3
4
5
6
7
V
IN
(V)
V
OUT
(V)
CPH6401,MA2Q737,CDRH104R/22
H
50mA
I
OUT
=0.1mA
100mA
200mA
SINGLE-COIL PWM CONTROL STEP-UP/DOWN TYPE SWITCHING REGULATOR CONTROLLER
S-8460
Rev.1.1
_00
28
Seiko Instruments Inc.
5.Ripple voltage characteristics
(31) S-8460B00AFT(V
OUT
=3.3 V)
(32) S-8460B00AFT(V
OUT
=3.3 V)
0
10
20
30
40
50
0
2
4
6
8 10 12 14 16 18
V
IN
(V)
Ripple Vrip (mV
)
CPH6401,MA2Q737,CDRH104R/22
H
200mA
66mA
I
OUT
=5mA
0
10
20
30
40
50
0
2
4
6
8 10 12 14 16 18
V
IN
(V)
Ripple Vrip (mV
)
CPH6401,MA2Q737,CDRH104R/10
H
200mA
66mA I
OUT
=5mA
(33) S-8460B00AFT(V
OUT
=3.3 V)
0
10
20
30
40
50
0
2
4
6
8 10 12 14 16 18
V
IN
(V)
Ripple Vrip (mV
)
CPH6401,MA2Q737,CDRH104R/47
H
200mA
66mA
I
OUT
=5mA
(34) S-8460B00AFT(V
OUT
=2.5 V)
(35) S-8460B00AFT(V
OUT
=5.0 V)
0
10
20
30
40
50
0
2
4
6
8 10 12 14 16 18
V
IN
(V)
Ripple Vrip (mV
)
CPH6401,MA2Q737,CDRH104R/22
H
200mA
50mA
I
OUT
=5mA
0
10
20
30
40
50
0
2
4
6
8 10 12 14 16 18
V
IN
(V)
Ripple Vrip (mV
)
CPH6401,MA2Q737,CDRH104R/22
H
200mA
100mA
I
OUT
=5mA
0.170.05
9
1
8
16
5.10.2
0.220.08
0.65
No.
TITLE
SCALE
UNIT
mm
Seiko Instruments Inc.
No. FT016-A-P-SD-1.1
FT016-A-P-SD-1.1
TSSOP16-A-PKG Dimensions
4.00.1
2.00.1
1.5
+0.1
-0
1.60.1
8.00.1
4.20.2
6.5
+0.4
-0.2
0.30.05
1.50.1
(7.2)
No.
TITLE
SCALE
UNIT
mm
8
1
9
16
Seiko Instruments Inc.
No. FT016-A-C-SD-1.1
FT016-A-C-SD-1.1
TSSOP16-A-Carrier Tape
Feed direction
No.
TITLE
SCALE
UNIT
mm
17.41.0
21.41.0
17.4
+2.0
-1.5
2.00.5
13.00.2
210.8
Seiko Instruments Inc.
No. FT016-A-R-SD-1.1
FT016-A-R-SD-1.1
TSSOP16-A- Reel
Enlarged drawing in the central part
QTY.
2,000
The information described herein is subject to change without notice.
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