1
FN7435.5
EL7532
Monolithic 2A Step-Down Regulator
The EL7532 is a synchronous, integrated FET 2A step-down
regulator with internal compensation. It operates with an
input voltage range from 2.5V to 5.5V, which accommodates
supplies of 3.3V, 5V, or a single Li-Ion battery source. The
output can be externally set from 0.8V to V
IN
with a resistive
divider.
The EL7532 features PWM mode control. The operating
frequency is typically 1.5MHz. Additional features include a
100ms Power-On-Reset output, <1A shut-down current,
short-circuit protection, and over-temperature protection.
The EL7532 is available in the 10-pin MSOP package,
making the entire converter occupy less than 0.18 in
2
of
PCB area with components on one side only. The package is
specified for operation over the full -40C to +85C
temperature range.
Pinout
Features
2A continuous current (from -40C to +85C)
Less than 0.18 in
2
footprint for the complete 2A converter
Max height 1.1mm MSOP10
1.5MHz (typ.) switching frequency
100ms Power-On-Reset output (POR)
Internally-compensated voltage mode controller
Up to 94% efficiency
<1A shut-down current
Overcurrent and over temperature protection
Pb-Free plus anneal available (RoHS compliant)
Applications
PDA and pocket PC computers
Bar code readers
ADSL Modems
Portable instruments
Li-Ion battery powered devices
ASIC/FPGA/DSP supplies
Set Top Boxes
Typical Application Schematic
Ordering Information
PART NUMBER
(BRAND)
PACKAGE
TAPE &
REEL
PKG.
DWG. #
EL7532IY
(BABAA)
10-Pin MSOP
-
MDP0043
EL7532IY-T7
(BABAA)
10-Pin MSOP
7"
MDP0043
EL7532IY-T13
(BABAA)
10-Pin MSOP
13"
MDP0043
EL7532IYZ
(BAARA) (Note)
10-Pin MSOP
(Pb-free)
-
MDP0043
EL7532IYZ-T7
(BAARA) (Note)
10-Pin MSOP
(Pb-free)
7"
MDP0043
EL7532IYZ-T13
(BAARA) (Note)
10-Pin MSOP
(Pb-free)
13"
MDP0043
NOTE: Intersil Pb-free plus anneal products employ special Pb-free
material sets; molding compounds/die attach materials and 100%
matte tin plate termination finish, which are RoHS compliant and
compatible with both SnPb and Pb-free soldering operations. Intersil
Pb-free products are MSL classified at Pb-free peak reflow
temperatures that meet or exceed the Pb-free requirements of
IPC/JEDEC J STD-020.
SGND
FB
VDD
RSI
VIN
EN
LX
POR
PGND
VO
1
2
3
4
10
9
8
7
5
6
* V
O
= 0.8V * (1 + R
2
/ R
1
)
1.8H
V
O
(1.8V@ 2A)
C
1
R
2
*
R
1
*
124k
100k
C
2
V
IN
(2.5V-6V)
10F
10F
L
1
0.1F
R
3
100
C
3
VIN
VDD
VO
LX
EN
POR
RSI
FB
SGND
PGND
EL7532
Data Sheet
August 12, 2005
CAUTION: These devices are sensitive to electrostatic discharge; follow proper IC Handling Procedures.
1-888-INTERSIL or 1-888-468-3774
|
Intersil (and design) is a registered trademark of Intersil Americas Inc.
Copyright Intersil Americas Inc. 2004, 2005. All Rights Reserved.
All other trademarks mentioned are the property of their respective owners.
2
FN7435.5
August 12, 2005
IMPORTANT NOTE: All parameters having Min/Max specifications are guaranteed. Typ values are for information purposes only. Unless otherwise noted, all tests are
at the specified temperature and are pulsed tests, therefore: T
J
= T
C
= T
A
NOTE:
1.
JA
is measured in free air with the component mounted on a high effective thermal conductivity test board with "direct attach" features. See
Tech Brief TB379.
Absolute Maximum Ratings
(T
A
= 25C)
Thermal Information
V
IN
, V
DD
, POR to SGND . . . . . . . . . . . . . . . . . . . . . . -0.3V to +6.5V
LX to PGND . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to (V
IN
+ +0.3V)
RSI, EN, V
O
, FB to SGND . . . . . . . . . . . . . . . -0.3V to (V
IN
+ +0.3V)
PGND to SGND . . . . . . . . . . . . . . . . . . . . . . . . . . . . . -0.3V to +0.3V
Peak Output Current . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2.4A
ESD Classification
Human Body Model (Per JESD22-A114-B) . . . . . . . . . . . . Class 2
Thermal Resistance (Typical)
JA
(C/W)
MSOP10 Package (Note 1) . . . . . . . . . . . . . . . . . . .
115
Operating Ambient Temperature . . . . . . . . . . . . . . . .-40C to +85C
Storage Temperature . . . . . . . . . . . . . . . . . . . . . . . .-65C to +150C
Junction Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . +125C
CAUTION: Stresses above those listed in "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress only rating and operation of the
device at these or any other conditions above those indicated in the operational sections of this specification is not implied.
Electrical Specifications
V
DD
= V
IN
= V
EN
= 3.3V, C1 = C2 = 10F, L = 1.8H, V
O
= 1.8V, unless otherwise specified.
PARAMETER
DESCRIPTION
CONDITIONS
MIN
TYP
MAX
UNIT
DC CHARACTERISTICS
V
FB
Feedback Input Voltage
790
800
810
mV
I
FB
Feedback Input Current
250
nA
V
IN
, V
DD
Input Voltage
2.5
5.5
V
V
IN,OFF
Minimum Voltage for Shutdown
V
IN
falling
2
2.2
V
V
IN,ON
Maximum Voltage for Startup
V
IN
rising
2.2
2.4
V
I
DD
Supply Current
PWM, V
IN
= V
DD
= 5V
400
500
A
EN = 0, V
IN
= V
DD
= 5V
0.1
1
A
R
DS(ON)-PMOS
PMOS FET Resistance
V
DD
= 5V, wafer test only
52
80
m
R
DS(ON)-NMOS
NMOS FET Resistance
V
DD
= 5V, wafer test only
35
65
m
I
LMAX
Current Limit (GBD)
3
A
T
OT,OFF
Over-temperature Threshold (GBD)
T rising
145
C
T
OT,ON
Over-temperature Hysteresis (GBD)
T falling
130
C
I
EN
, I
RSI
EN, RSI Current
V
EN
, V
RSI
= 0V and 3.3V
-1
1
V
V
EN1
, V
RSI1
EN, RSI Rising Threshold
V
DD
= 3.3V
2.4
V
V
EN2
, V
RSI2
EN, RSI Falling Threshold
V
DD
= 3.3V
0.8
V
V
POR
Minimum V
FB
for POR, WRT Targeted
V
FB
Value
V
FB
rising
95
%
V
FB
falling
86
%
V
OLPOR
POR Voltage Drop
I
SINK
= 5mA
35
70
mV
V
LINEREG
Line Regulation (GBD)
V
IN
= 2.5V to 6V, I
OUT
= 2A, V
OUT
= 1.8V
0.1
%/V
V
LOADREG
Load Regulation (GBD)
V
IN
= 3.3V, V
OUT
= 1.8V, I
OUT
= 0 to 2A
0.5
%
AC CHARACTERISTICS
F
PWM
PWM Switching Frequency
1.35
1.5
1.65
MHz
t
RSI
Minimum RSI Pulse Width (GBD)
Guaranteed by design
25
50
ns
t
SS
Soft-start Time (GBD)
650
s
t
POR
Power On Reset Delay Time (GBD)
80
100
120
ms
GBD = Guaranteed By Design
EL7532
3
FN7435.5
August 12, 2005
Block Diagram
Pin Descriptions
PIN NUMBER
PIN NAME
PIN FUNCTION
1
SGND
Negative supply for the controller stage
2
PGND
Negative supply for the power stage
3
LX
Inductor drive pin; high current digital output with average voltage equal to the regulator output voltage
4
VIN
Positive supply for the power stage
5
VDD
Power supply for the controller stage
6
RSI
Resets POR timer; Connect to ground if not used
7
EN
Enable; Can be connected directly to the VIN for enable
8
POR
Power on reset open drain output; Leave open if not used
9
VO
Output voltage sense pin
10
FB
Voltage feedback input; connected to an external resistor divider between V
O
and SGND for variable
output
-
+
-
+
-
+
CONTROL
LOGIC
PWM
COMPEN-
SATION
POR
CLOCK
1.5MHz
SOFT-
START
BANDGAP
REFERENCE
TEMPERATURE
SENSE
+
V
IN
LX
PGND
POR
V
O
FB
EN
V
DD
SGND
10pF
5M
124K
100K
10F
2.5V-
5V
EN
PWM
COMPARATOR
N-DRIVER
P-DRIVER
CURRENT
LIMIT
1.8
10F
100K
PG
1.8V
2A
RSI
RAMP
GENERATOR
UNDER-
VOLTAGE
LOCKOUT
1
2
5
9
10
7
6
4
3
8
EL7532
4
FN7435.5
August 12, 2005
Typical Performance Curves
FIGURE 1. EFFICIENCY vs I
OUT
@ V
IN
=5V
FIGURE 2. EFFICIENCY vs I
OUT
@ V
IN
=3.3V
FIGURE 3. EFFICIENCY vs I
OUT
@ V
IN
=2.5V
FIGURE 4. LINE REGULATION
FIGURE 5. LOAD REGULATION @ V
IN
=5V
FIGURE 6. LOAD REGULATION @ V
IN
=3.3V
0
1
0.5
1.5
2
2.5
100
80
60
40
20
0
I
OUT
(A)
EFFICIENCY (%)
MAXIMUM EFFICIENCY,
=95%
V
O
=1.2V
V
O
=3.3V
V
O
=1.8V
0
1
0.5
1.5
2
2.5
100
80
60
40
20
0
I
OUT
(A)
EFFICIENCY (%)
MAXIMUM EFFICIENCY,
=95%
V
O
=1.2V
V
O
=2.5V
V
O
=1.8V
0
1
0.5
1.5
2
2.5
100
80
60
40
20
0
I
OUT
(A)
EFFICIE
N
CY
(%)
MAXIMUM EFFICIENCY,
=94%
V
O
=1.8V
V
O
=1.2V
2.5
4
3
5
5.5
6
1
0.6
0.2
-0.2
-0.6
-1
V
IN
(V)
V
O
CHANGE
S
(%
)
4.5
3.5
I
O
=2A
V
O
=0.8V
V
O
=2.5V
V
O
=3.3V
0
1.5
0.5
2.5
1
0.6
0.2
-0.2
-0.6
-1
I
OUT
(A)
V
O
CHANGE
S
(%
)
2
1
V
O
=0.8V
V
O
=3.3V
0
1.5
0.5
2.5
1
0.6
0.2
-0.2
-0.6
-1
I
OUT
(A)
V
O
CHANGES
(
%
)
2
1
V
O
=0.8V
V
O
=2.5V
EL7532
5
FN7435.5
August 12, 2005
FIGURE 7. LOAD REGULATION @ V
IN
=2.5V
FIGURE 8. LOAD REGULATION @ V
IN
=2.5V
FIGURE 9. START-UP 1
FIGURE 10. START-UP 2
FIGURE 11. POR FUNCTION
FIGURE 12. TRANSIENT RESPONSE
Typical Performance Curves
(Continued)
0
1.5
0.5
2.5
1
-0.5
-1
I
OUT
(A)
V
O
CHANGES
(
%
)
2
1
V
O
=1.8V
V
O
=0.8V
0.5
0
100mV/d
10mV/d
0.5A/d
1s/d
i
L
V
IN
V
O
V
LX
2V/d
V
IN
(1V/d)
I
IN
(0.5A/d)
V
O
(1V/d)
0.5ms/d
V
IN
(2V/d)
POR
(2V/d)
V
O
(2V/d)
50ms/d
V
IN
(2V/d)
POR
(2V/d)
V
O
(2V/d)
50ms/d
RSI
(2V/d)
2A
50mV/d
0.1A
0.5ms/d
I
O
V
O
EL7532
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