This monolithic integrated circuit contains all the control circuitry for a regulating power supply inverter or switching regulator. Included a 16-pin dual-in-line package is the voltage reference, error amplifier, oscillator, pulse-width modulator, pulse steering flip-flop, dual alternating output switches and current-limiting and shut-down circuitry. This device can be used for switching regulators of either polarity, transformer-coupled DC-to-DC converters, transformerless voltage doublers and polarity converters, as well as other power control applications. The SG3524 is designed for commercial applications to +70°C.
INVERT INPUT 1 NON-INV INPUT 2 OSC OUTPUT 3 (+)CL SENSE 4 ()CL SENSE 7 16 VREF 15 VIN 14 EMITTER B 13 COLLECTOR B 12 COLLECTOR A 11 EMITTER A 10 SHUTDOWN 9 TOP VIEW COMPENSATION
· Complete PWM power control circuitry· Single ended or push-pull outputs· Line and load regulation 0.2%· 1% maximum temperature variation· Total supply current is less than 10mA· Operation beyond 100kHz
DESCRIPTION 16-Pin Plastic Dual In-Line Package (DIP) 16-Pin Ceramic Dual In-Line Package (CERDIP) 16-Pin Small Outline (SO) Package
VREF 16 VIN 15 REF REG +5V TO ALL INTERNAL CIRCUITRY +5V OSCILLATOR 3 OUTPUT FLIP FLOP
SYMBOL VIN IOUT IREF PD Input voltage Output current (each output) Reference output current Oscillator charging current Power dissipation Package limitation Derate above 25°C TA TSTG Operating temperature range Storage temperature range +150 mW mW/°C °C PARAMETER RATING UNIT V mA
+70°C, VIN=20V, and f=20kHz, unless otherwise specified. SYMBOL PARAMETER TEST CONDITIONS LIMITS Min VREF=0, TA=25°C Over operating temperature range TA=25°C CT=0.001 µF, RT=2k RT and CT constant 40V, TA=25°C Over operating temperature range Pin TA=25°C CT=0.01 µF, TA=25°C % each output "ON" Zero duty cycle Maximum duty cycle Pin 9=2V with error amplifier set for maximum out, TA=25°C Typ Max 30 50 UNIT
VOUT Output voltage Line regulation Load regulation Ripple rejection ISC Short circuit current limit Temperature stability Long-term stability mA % mV/kHz kHz V dB MHz µA mV mV/°C V
fMAX Maximum frequency Initial accuracy Voltage stability Temperature stability Output amplitude Output pulse width
VOS IBIAS VCM CMRR BW VOUT Input offset voltage Input bias current Open-loop voltage gain Common-mode voltage Common-mode rejection ratio Small-signal bandwidth Output voltage Duty cycle Input threshold Input threshold IBIAS Input bias current Sense voltage Sense voltage T.C. VCM Common-mode voltage
to +70°C, VIN = 20V, and = 20kHz, unless otherwise specified. SYMBOL PARAMETER TEST CONDITIONS LIMITS Min RC=2k, TA=25°C Typ Max UNIT
Collector-emitter voltage (breakdown) Collector-leakage current Saturation voltage Emitter output voltage tR tF Rise time Fall time (excluding oscillator charging current, error and current limit dividers, and with outputs open) V µs
An internal series regulator provides a nominal 5V output which is used both to generate a reference voltage and is the regulated source for all the internal timing and controlling circuitry. This regulator may be bypassed for operation from a fixed 5V supply by
connecting Pins 15 and 16 together to the input voltage. In this configuration, the maximum input voltage is 6.0V. This reference regulator may be used a 5V source for other circuitry. It will provide 50mA of current itself and can easily be expanded to higher currents with an external PNP as shown in Figure 3.
IS OSC OUT VREF 2k 1W RAMP VIN 2k 2 N.I. INPUT 1 INV. INPUT 9 COMP SHUT DOWN 4 SG3524 CURRENT LIMIT 2k 1W OUTPUTS