FA551X series
FA5510P (N), FA5511P (N)
FA5514P (N), FA5515P (N)
■
Description
The FA551X series are the PWM type switching power supply
control ICs that can directly drive power MOSFET. These ICs
use a CMOS device with high dielectric strength (30V) to
implement low power consumption. These ICs contain many
function in a small 8-pin package. With these ICs, a high-
performance and compact power supply can be created
because not many external discrete components are needed.
CMOS IC
For Switching Power Supply Control
FA551X
■
Dimensions, mm
SOP-8
8
5
1
4.9
4
+0.1
–0.05
6.0
±0.2
3.9
■
Features
• Low current consumption by CMOS process with high
dielectric strength (30V)
• Standby current of 2µA or less (at Vcc=14V), and operating
current of 1.5mA (typ)
• Overvoltage protection function detecting the Vcc voltage
• A drive circuit for connecting a power MOSFET directly
• Output peak current: ±1.5A
• Pulse-by-pulse overcurrent limiting function
• Overload protection function (latch or non-latch mode selectable)
• Output ON-OFF function by external signal
• Latch-mode overvoltage shutdown function
• Undervoltage lockout function (16.5V ON / 9V OFF)
• Reference voltage output (5V)
• 8-pin package (DIP/SOP)
0.4
±0.1
1.27
DIP-8
8
5
1
9.3
4
1.5
±0.3
6.4
3.0min 4.5max
3.3
0~8
°
■
Block diagram
FA5510P (N), FA5511P (N)
CS(8)
REF
(7)
5V VCC
ENB
5V REF
8.5V/7.9V
0.8V
3.5V
ENB
4V
PWM
Dmax
FA5510: 46%
FA5511: 70%
OSC
RT CT
OUT
PUT
0.8V/0.68V 5.2µA
0.95mA
15.5V
15.5V
UVLO
0.05
0.25
–
7.62
0~15
˚
0~1
5˚
VCC(6)
2.54
0.46
±0.1
16.5V/9V
FB
(2)
OUT
(5)
Pin Pin
Function
No. symbol
1
RT
FB
IS
GND
OUT
VCC
REF
CS
Oscillator timing
resistor
Feedback
Overcurrent
detection
Ground
Output
Power supply
Reference voltage
Soft-start and
ON/OFF control
Description
Setting oscillation frequency
Input of PWM comparator
Input of the overcurrent
limiting function
Ground
Output for driving a power
MOSFET
Power supply
Reference voltage output (5V)
Soft-start, ON/OFF function and
latch-mode shutdown operations
R
+0.24V
GND
(4)
2
3
4
5
6
7
8
QB
S Q
FF
5V Controlled block
RT(1)
IS+(3)
FA5514P (N), FA5515P (N)
CS(8)
REF
(7)
5V VCC
ENB
5V REF
8.5V/7.9V
0.8V
3.5V
ENB
4V
PWM
Dmax
FA5514: 46%
FA5515: 70%
OSC
RT CT
OUT
PUT
0.8V/0.68V 5.2µA
0.95mA
15.5V
15.5V
UVLO
VCC(6)
Type
FA5510P
OUT
(5)
Max. duty
cycle (typ.)
46%
70%
46%
70%
Polarity of overcurrent Package
detection
+
+
–
–
DIP-8
SOP-8
DIP-8
SOP-8
DIP-8
SOP-8
DIP-8
SOP-8
16.5V/9V
FA5510N
FA5511P
FA5511N
FB
(2)
R
-0.17V
GND
(4)
FA5514P
FA5514N
FA5515P
FA5515N
QB
S Q
FF
5V Controlled block
RT(1)
IS-(3)
1.8max
+0.1
0.20
1
FA551X
■
Absolute maximum ratings
I
tem
Supply Voltage
Output peak current
FB pin input voltage
IS pin input voltage
REF pin source current
CS pin sink current
Total power dissipation (Ta=25˚C)
Ambient temperature
Maximum junction temperature
Storage temperature
Low impedance source (I
CC
>15mA)
Internal zener clamp (I
CC
<15mA)
Symbol
V
CC1
V
CC2
I
OUT
V
FB
V
IS
I
REF
I
CS
Pd
Ta
Tj
Tstg
Rating
30
Self limiting
±1.5
–0.3 to 5.0
–0.3 to 5.0
–10
+2.0
800 (DIP-8)
400 (SOP-8)
–30 to +85
125
–40 to +150
Unit
V
V
A
V
V
mA
mA
mW
˚C
˚C
˚C
Note: There are cases where the IC cannot output the rating current depending on Vcc voltage or temperature.
Maximum power dissipation curve
400mW (SOP)
800mW (DIP)
Max. power
dissipation
0
–30
25
85
125
Ambient temperature Ta [˚C]
■
Recommended operating conditions
Item
Supply voltage
Oscillation frequency
REF-GND capacitor
Soft start capacitor
Symbol
V
CC
f
OSC
Cref
C
S
Min.
10
10
0.1
0.01
0.47
1
Typ.
Max.
28
500
Unit
V
kHz
µF
µF
2
FA551X
■
Electrical characteristics
(V
CC
=18V, R
T
=47kΩ, Ta=25˚C)
Reference voltage section (REF pin)
Item
Reference voltage
Line regulation
Load regulation
Temperature stability
Symbol
V
REF
V
dv1
V
dv2
V
dT
Test condition
Tj=25˚C
V
CC
=10 to 28V
I
L
=0 to 10mA, V
CC
=18V
Ta=–30 to 85˚C
–40
Min.
4.75
Typ.
5.00
±6
–12
±0.5
Max.
5.25
±20
Unit
V
mV
mV
mV/˚C
Oscillator section (RT pin)
Item
Oscillation frequency
Voltage stability
Temperature stability
Symbol
f
OSC
f
dv
f
dT
Test condition
R
T
=47kΩ, Tj=25˚C
V
CC
=10 to 28V
Ta=–30 to 85˚C
Min.
92.6
Typ.
100
±1.0
±0.02
Max.
107.4
Unit
kHz
%
%/˚C
Pulse width modulation circuit section (FB pin)
Item
FB pin source current
Input threshold voltage (FB pin)
Maximum duty cycle
Symbol
Test condition
FA5510/14
Min.
Typ.
1
1.92
42
46
50
66
FA5511/15
Max. Min.
0.9
Typ.
1
2.40
70
74
Max.
V
V
%
Unit
I
FB
V
TH FB0
V
TH FBM
D
MAX
V
FB
=0
Duty cycle =0%
Duty cycle =
D
MAX
–855 –720 –585 –855 –720 –585 µA
0.9
Overcurrent limiting circuit section (IS pin)
Item
Input threshold voltage (IS pin)
Source current (IS pin)
Delay time
Symbol
V
THIS
I
IS
t
pdIS
V
IS
=0V
150
Test condition
FA5510/11
Min.
220
Typ.
240
260
±5
FA5514/15
Max. Min.
–28
Typ.
–20
150
Max.
–12
µA
ns
Unit
–190 –170 –150 mV
Soft start circuit section (CS pin)
Item
Charge current (CS pin)
Input threshold voltage (CS pin)
Symbol
Test condition
FA5310/14
Min.
Typ.
–5.2
1.0
1.92
–3.2
FA5311/15
Max. Min.
–7.2
0.90
Typ.
–5.2
1.0
2.40
Max.
–3.2
µA
V
V
Unit
I
CHG
V
TH CS0
V
TH CSM
V
CS
=1V, Tj=25˚C –7.2
Duty cycle =0%
Duty cycle =
D
MAX
0.90
Output ON/OFF control circuit section (CS pin)
Item
Source current (CS pin)
ON/OFF control threshold voltage (CS pin)
Hysteresis voltage
Symbol
I
S0CS
V
THON
V
THOFF
V
THOHS
Test condition
V
CS
=0V, Tj=25˚C
OFF→ON, Tj=25˚C
ON→OFF, Tj=25C
0.50
Min.
–7.2
Typ.
–5.2
0.8
0.68
0.12
Max.
–3.2
0.93
Unit
µA
V
V
V
3
FA551X
Latch-mode cutoff circuit section (CS pin)
Item
Sink current (CS pin)
Cutoff threshold voltage (CS pin)
Hysteresis voltage
Symbol
I
SICS
V
TH CSF
V
TH CSN
V
THHIS
Test condition
V
CS
=6.5V, V
FB
=1V, Tj=25˚C
ON→OFF, Tj=25˚C
OFF→ON, Tj=25˚C
Min.
18
8.0
7.4
Typ.
30
8.5
7.9
0.6
Max.
45
9.0
8.4
Unit
µA
V
V
V
Overload cutoff circuit section (FB pin)
Item
Overload threshold voltage (FB pin)
Symbol
V
TH FB
Test condition
Min.
3.2
Typ.
3.5
Max.
3.8
Unit
V
Overvoltage cutoff circuit section (VCC pin)
Item
Overvoltage threshold voltage (VCC pin)
Cutoff operating supply current (VCC pin)
Charge current (CS pin)
Symbol
V
TH VCC
I
VCC
I
S0CS2
Test condition
Tj=25˚C
Tj=25˚C, V
CC
=V
THVCC
V
CS
=6.5V
–1.4
Min.
30
Typ.
31.8
14
–0.95
–0.5
Max.
34
Unit
V
mA
mA
Undervoltage lockout circuit section (VCC pin)
Item
OFF-to-ON threshold voltage
ON-to-OFF threshold voltage
Hysteresis voltage
Symbol
V
CC ON
V
CC OFF
V
HYS
Test condition
Tj=25˚C
Tj=25˚C
Tj=25˚C
Min.
15.5
8.5
6.8
Typ.
16.5
9.0
7.5
Max.
17.5
10.0
8.2
Unit
V
V
V
Output circuit section (OUT pin)
Item
Low output voltage
High output voltage
Rise time
Fall time
Symbol
V
OL
V
OH
tr
tf
Test condition
I
OL
=100mA
I
OH
=–100mA, V
CC
=18V
C
L
=1nF
C
L
=1nF
15
Min.
Typ.
0.7
16.5
40
25
Max.
1.5
Unit
V
V
ns
ns
Supply current (VCC pin)
Item
Stand-by current
Startup current
Operating-state supply current
OFF-state supply current
Latch mode supply current
Symbol
I
CCSTB
I
CCST
I
CCOP
I
CCOF
I
CCL
Test condition
V
CC
=14V
V
CC
=OFF-to-ON threshold voltage
No load
V
CC
=17V, CS=0V
V
CC
=10V
12
1.5
80
45
Min.
Typ.
Max.
2
30
2.5
200
80
Unit
µA
µA
mA
µA
µA
4
FA551X
■
Characteristic curves
(V
CC
=18V, R
T
=47kΩ, Ta=25˚C)
Oscillation frequency (f
OSC
) vs.
timing resistor resistance (R
T
)
1000
Oscillation frequency (f
OSC
) vs. supply voltage (V
CC
)
100.1
100.08
100.06
100
100.04
fosc (kHz)
fosc (kHz)
100.02
100
99.98
99.96
99.94
99.92
10
1
1
10
100
1000
R
T
(kΩ)
99.9
10
15
20
25
30
Vcc (V)
Oscillation frequency (f
OSC
) vs.
junction temperature (Tj)
102
101.5
101
FB pin source current (I
FB
) vs. FB pin voltage (V
FB
)
0
-100
-200
fosc (kHz)
-300
100.5
100
99.5
99
98.5
–50
I
FB
(µA)
-400
-500
-600
-700
-800
0
1
2
3
4
5
0
50
100
150
V
FB
(V)
Tj (˚C)
Maximum duty cycle (D
MAX
) vs. timing resitor resistance (R
T
)
FA5510/14
49
48
Maximum duty cycle (D
MAX
) vs. timing resitor resistance (R
T
)
FA5511/15
72
71
47
D
MAX
(%)
D
MAX
(%)
1
10
100
1000
46
45
44
43
42
70
69
68
67
1
10
100
1000
R
T
(kΩ)
R
T
(kΩ)
5
