Document
Semiconductor
S494
Pulse Width Modulation
Description
The S494 is a monolithic integrated circuit which includes all the necessary building blocks for the design of pulse width modulate(PWM) switching power supplies, including push-pull, bridge and series configuration. The device can operate at switching frequencies between 1KHz and 300KHz and output voltage up to 40V. The S494 is specified over an operating temperature range of -40℃to85℃.
Features
• Uncommitted output transistors capable of 200mA source or sink • Internal protection from double pulsing of out-puts with narrow pulse widths or with supply voltages bellows specified limits • Easily synchronized to other circuits • Dead time control comparator • Output control selects single-ended or push-pull operation
Ordering Information
Type NO. S494 Marking S494 Package Code SOP-16
Outline Dimensions
unit :
mm
PIN Connections 1. Non-INV Input 2. INV Input 3. Feed-Back 4. Dead-Time Control 5. CT 6. RT
7. GND 8. C1 9. E1 10. E2 11. C2 12. Vcc 13 Output Control 14. Ref Out 15. INV-Input 16. Non-INV Input
KSI-K003-000
1
S494
Absolute Maximum Ratings
Characteristic
supply voltage Voltage From Any Pin to Ground (except pin 8 and pin 11) Output Collector Voltage Peak Collector Current Power Dissipation Operating Temperature Storage Temperature
Ta=25°C
Symbol
VCC VIN VC1, VC2 IC1, IC2 PD Topr Tstg
Ratings
42 VCC+0.3 42 250 1500 -40 ~ 85 -65 ~ 150
Unit
V V V mA mW °C °C
Recommended Operating Condition
Characteristic
supply voltage Voltage on Any Pin Except Pin 8 and 11(Referenced to Ground) Output Voltage Output Collector Current Timing Capacitor Timing Capacitor Timing Resistor Oscillator Frequency
Symbol
VCC VIN VC1, VC2 IC1, IC2 Ct Ct Rt fOSC
Min.
7 -0.3 -0.3 470 1.8 1
Max.
40 VCC+0.3 40 200 10 500 300
Unit
V V V mA PF ㎌ ㏀ KHz
Electrical Characteristics Reference Section
Characteristic
Reference Voltage Line Regulation Load Regulation Temperature Coefficient
Symbol
Vref VLINE VLOAD -
Test Condition
Iref = 1.0mA 7V < Vcc < 40V
Min. Typ. Max.
4.75 5.00 2 1 0.01 5.25 25 15 0.03
Unit
V mV mV %/°C
1mA< IREF <10mA
0°C < Ta <70°C
Oscillator Section
Characteristic
Oscillator Frequency Oscillator Frequency Change Over Operating Temperature Range
Symbol
fOSC Δ fSOC
Test Condition
Ct=0.01 ㎌, Rt=12 ㏀ Ct=0.01 ㎌, Rt=12 ㏀
Min. Typ. Max.
10 2
Unit
㎑ %
KSI-K003-000
2
S494
Dead Time Control Section
Characteristic
Input Bias Current (Pin4) Max. Duty cycle, Each Output Input Threshold Voltage Zero Duty Max Duty
Symbol
IIB(DT) DC(Max) VTH
Test Condition
Vcc = 15V, 0V < V4 < 5.25V Vcc = 15V, Pin4 = 0V, Output Control Pin = Vref -
Min. Typ. Max.
43 0 -2 3 -10 45 3.3 -
Unit
㎂
%
V
Error Amplifier Section
Characteristic
Input Offset Voltage Input Offset Current Input Bias Current Input Common Mode voltage Range Large Signal Open Loop Voltage Range Unity Gain Band width
Symbol
VIOS IIOS IIB VICR GVO fC
Test Condition
V3 = 2.5V V3 = 2.5V V3 = 2.5V 7V ≤ VCC ≤ 40V 0.5V ≤ V3 ≤ 3.5V -
Mi.