FA3621F
1
s
Dimensions, mm
LQFP-48
0~7
9.0
0.3
0.10
0.06
0.5
0.1
0.2
0.06
0.127
0.05
1.45 max
7.0
1
12
36
25
48
37
13
24
9.0
0.3
0.5
0.2
7.0
7.8
8.0
CMOS IC
For Switching Power Supply Control
s
Description
FA3621F is a control IC for 6-channel DC-DC converter.
This IC can directly drive a Nch/Pch-MOSFET.
This IC is suitable to reduce converter size because it has
many functions in a small package LQFP-48.
s
Features
6-channel PWM control with MOSFET direct driving :
5-channel for Pch-MOSFET, 1channel for Nch-MOSFET
Low input voltage: 4.5V to 20V
1.5% high accuracy bandgap reference
Low power consumption by means of CDMOS
Standby mode: 10
A(max.)
Operating mode: 6mA(max.)
Soft start function for each channel
ON/OFF function for each channel
Timer latch for short protection
Overheat protection
Undervoltage lockout
Wide range of operation frequency: 50kHz to 1MHz
Package: LQFP-48(Thin and small)
s
Application
VTR-camera, digital-steel-camera and portable equipment
FA3621F
FA3621F
3
s
Recommended operating conditions
Item
Symbol
Min.
Max.
Unit
Power supply voltage
V
CC
4.5
18.0
V
Input voltage for logic input
V
LOG
0.0
5.25
V
Oscillation frequency
f
OSC
50
1000
kHz
Oscillator timing resistor
R
T
6.8
100
k
Oscillator timing capacitor
C
T
68
1000
pF
CREF terminal by-pass capacitor
C
REF
0.01
F
VREF terminal output current
I
REF
60
0
A
Pin
Pin
Description
No.
symbol
1
RT
Oscillator timing resistor
2
CT2
(Not connect any component)
3
CT1
Oscillator timing capacitor
4
VREF
Reference voltage output
5
CREF
Capacitor for reference voltage output
6
CP
Timing capacitor for timer latch delay
7
FB4
Ch. 4 output of error amplifier
8
IN4+
Ch. 4 non-inverting input to error amplifier
9
IN4
Ch. 4 inverting input to error amplifier
10
IN3
Ch. 3 inverting input to error amplifier
11
IN3+
Ch. 3 non-inverting input to error amplifier
12
VREG
Regulated voltage output
13
FB3
Ch. 3 output of error amplifier
14
IN2
Ch. 2 inverting input to error amplifier
15
FB2
Ch. 2 output of error amplifier
16
IN1
Ch. 1 inverting input to error amplifier
17
FB1
Ch. 1 output of error amplifier
18
FB5
Ch. 5 output of error amplifier
19
IN5+
Ch. 5 non-inverting input to error amplifier
20
IN5
Ch. 5 inverting input to error amplifier
21
IN6
Ch. 6 inverting input to error amplifier
22
GND1
Ground
23
OUT6b
ON/OFF switch for ch.6 power supply
24
FB6
Ch. 6 output of error amplifier
s
Absolute maximum ratings
Item
Symbol
Rating
Unit
Power supply voltage
V
CC
20.0
V
Source peak current
I
OUT
200
mA
Sink peak current
I
OUT
200
mA
Output peak current of OUT6b
I
OUT6b
500
mA
Input voltage for analog input
V
ANA
0.3 to +2.8
V
Input voltage for logic input
V
LOG
0.3 to +5.5
V
Total power dissipation
*
P
d
550
mW
Junction temperature
T
J
125
C
Ambient temperature
T
OP
20 to +85
C
Storage temperature
T
stg
40 to +125
C
*
Ta < 25
C
Pin
Pin
Description
No.
symbol
25
CS5
Soft start for Ch. 5
26
CS6
Soft start for Ch. 6
27
CNT6
Ch. 6 ON/OFF function
28
CNT5
Ch. 5 ON/OFF function
29
VCC2
Power supply for output stage
30
CS3/4
Soft start for Ch. 3 & Ch. 4
31
CS2
Soft start for Ch. 2
32
CS1
Soft start for Ch. 1
33
CNT3/4
Ch. 3 & Ch. 4 ON/OFF function
34
CNT2
Ch. 2 ON/OFF function
35
CNT1
Ch. 1 ON/OFF function
36
SYN
(Connect to GND1/ GND2 terminal)
37
VDRV
Bias for logic circuit of outputs
38
OUT5
Ch. 5 output (for Pch-MOSFET)
39
OUT6a
Ch. 6 output (for Nch-MOSFET)
40
(OPEN)
(Not connect any component)
41
OUT1
Ch. 1 output (for Pch-MOSFET)
42
GND2
Ground
43
OUT2
Ch. 2 output (for Pch-MOSFET)
44
OUT3
Ch. 3 output (for Pch-MOSFET)
45
OUT4
Ch. 4 output (for Pch-MOSFET)
46
VCC1
Power supply for control circuit
47
DT2
(Connect to DT1)
48
DT1
(Connect to DT2)
FA3621F
4
Oscillator section
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Oscillation frequency
f
OSC
R
T
=18k
,
C
T
=100pF
414
460
506
kHz
Frequency variation due to supply voltage change
f
dV
V
CC
=4.5 to 18V
1
3
%
Frequency variation due to temperature change
f
dT
T
a
=20 to +25
C
1.5
%
T
a
=+25 to +85
C
1.5
Error amplifier section
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Input offset voltage
V
IOF
10
mV
Input common mode voltage range
V
ICOM
0.2
1.7
V
Open-loop gain
A
VOL
70
75
dB
Unity-gain bandwidth
f
T
1.2
MHz
Output sink current
I
FBL
V
FB
=
1.0V
1.5
2.8
mA
Output source current
I
FBH
V
FB
=
0V
0.25
0.15
mA
PWM control section
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Maximum duty cycle
D
max
100
%
Soft-start circuit section 1 (CS1, CS2, CS3/4)
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Input threshold voltage
V
CSO
Duty cycle=0%
0.78
V
V
CS100
Duty cycle=100%
1.38
V
Charge current
I
CS
7.5
5.1
2.5
A
Soft-start circuit section 2 (CS5, CS6)
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Input threshold voltage
V
CSO
Duty cycle=0%
0.79
V
V
CS100
Duty cycle=100%
1.40
V
Charge current
I
CS
0
A
Regulated voltage section
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Output voltage
V
REG
2.40
2.67
2.95
V
s
Electrical characteristics (Ta=25
C, Vcc
1
=Vcc
2
=6V, C
T
=100pF, R
T
=18k
)
Reference voltage section
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Output voltage
V
REF
0.985
1.00
1.015
V
Line regulation
V
RLIN
V
CC
=4.5 to 18V
3
10
mV
Output voltage variation due to temperature change
V
RTa
T
a
=20 to +85
C
0.5
%
FA3621F
5
Overheat protection section
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Operating temperature
T
OH
125
135
145
C
Hysteresis width
T
OH
45
50
55
C
Output section 2 (OUT2, OUT3, OUT4, OUT5, OUT6a )
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
L-level ON resistance
R
ONL
I
O
=10mA
10
15
H-level ON resistance
R
ONH
I
O
=10mA
10
15
Rise time
tr
C
LOAD
=1000pF
40
60
ns
Fall time
tf
C
LOAD
=1000pF
55
80
ns
Output section 3 (OUT6b )
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
ON resistance
R
ON6b
I
O
=10mA
1
2
Overall device
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Standby current
I
CCO
3
10
A
Operating-state supply current
I
CC
Duty cycle=0%,
R
L=
4
6
mA
Short-circuit protection section
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Threshold voltage at CP
V
CPTH
1.90
2.16
2.42
V
Charge current at CP
I
CP
3.45
2.30
1.15
A
Threshold voltage at error amplifier output
V
FBTL
2.16
V
Output section 1 (OUT1)
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
L-level ON resistance
R
ONL
I
O
=10mA
6
10
H-level ON resistance
R
ONH
I
O
=10mA
6
10
Rise time
tr
C
LOAD
=1000pF
30
50
ns
Fall time
tf
C
LOAD
=1000pF
45
70
ns
ON/OFF logic input section
Item
Symbol
Test condition
Min.
Typ.
Max.
Unit
Input voltage for ON mode
V
DH
1.0
5.25
V
Input voltage for OFF mode
V
DL
0
0.4
V