Data Sheet

KA7552A/KA7553A
www.onsemi.com
2
Absolute Maximum Ratings
Electrical Characteristics
(V
CC
= 18V, F
OSC
= 135kHz, T
A
= 25°C, unless otherwise specified)
Parameter Symbol Value Unit
Supply voltage V
CC
30 V
Output current I
O
±1.5 A
Input voltage at overcurrent detection pin V
IN(IS)
-0.3 to 4 V
Input voltage at FB pin V
IN(FB)
4V
Input current at CS pin I
IN(CS)
2mA
Total power dissipation (Ta = 25°C) P
D
800 mW
Operating temperature T
OPR
-25 to 85 °C
Storage temperature range T
STG
-65 to 150 °C
Junction temperature T
j
+125 °C
Parameter Symbol Conditions Min. Typ. Max. Unit
OSCILLATOR SECTION
Initial accuracy F
OSC
C
T
= 360pF, T
J
= 25°C 125 135 145 kHz
Frequency variation 1 ∆F/∆VV
CC
= 10V to 30V - ±1 ±3%
Frequency variation 2
(Note1)
∆F/∆VT
A
= 25°C to 85°C-±1.5 - %
Ramp high voltage V
RH
C
T
= 360pF, T
J
= 25°C 2.80 3.08 3.30 V
Ramp low voltage V
RL
C
T
= 360pF, T
J
= 25°C 0.6 0.9 1.2 V
Amplitude V
OSC
V
PIN7
, peak to peak 1.80 2.18 2.50 V
PULSE WIDTH MODULATION SECTION
Input threshold voltage(pin2) V
TH(FBD)
Duty cycle = 0% 0.6 0.75 0.95 V
Input threshold voltage(pin2)
(Note1)
V
TH(FB1)
(KA7552) Duty cycle = Dmax 1 2.1 2.3 2.6 V
V
TH(FB2)
(KA7553) Duty cycle = Dmax 2 1.6 1.8 2.1 V
Max. duty cycle
D
(Max1)
(KA7552) - 66 70 74 %
D
(Max2)
(KA7553) - 43 46 49 %
Source current(pin2) I
SOURCE(FB)
V
PIN2
= 0V -660 -800 -960 uA
OVERCURRENT LIMIT SECTION
Input threshold voltage V
TH(IS)
- 0.21 0.24 0.27 V
Source current(pin3) I
SOURCE(IS)
V
PIN3
= 0V -300 -200 -100 uA
Deley time
(Note1)
T
D
- - 150 - ns
SOFT START SECTION
Charging current I
CHG
V
PIN8
= 0V -15 -10 -5 uA
Input threshold voltage(pin8) V
TH(CSO)
- 0.7 0.9 1.1 V
Input threshold voltage(pin8)
(Note1)
V
TH(CS1)
(KA7552) Duty cycle = Dmax 1 2.2 2.4 2.6 V
V
TH(CS2)
(KA7553) Duty cycle = Dmax 2 1.7 1.9 2.1 V
LATCH MODE SHUTDOWN CIRCUIT SECTION
Sink current(pin8) I
SINK(CS)
V
PIN8
= 6V, V
PIN2
= 1V 25 45 65 uA
Shutdown threshold voltage V
TH(SD,CS)
- 6.7 7.2 7.7 V
OVERLOAD SHUTDOWN SECTION
Shutdown threshold voltage V
TH(SD,FB)
- 2.6 2.8 3.1 V