UC3842BD1R2G

Product Summary

The UC3842BD1R2G is a high performance fixed frequency current mode controller. The UC3842BD1R2G is specifically designed for Off-Line and DC-DC converter applications offering the designer a cost-effective solution with minimal external component. The UC3842BD1R2G integrated circuits feature a trimmed oscillator for precise duty cycle control, a temperature compensated reference, high gain error amplifier, current sensing comparator, and a high current totem pole output ideally suited for driving a power MOSFET. Also included are protective features consisting of input and reference undervoltage lockouts each with hysteresis, cycle-by-cycle current limiting, programmable output deadtime, and a latch for single pulse metering.

Parametrics

UC3842BD1R2G absolute maximum ratings: (1)Bias and driver voltages (zero series impedance, see also total device spec), VCC, VC: 30 V; (2)Total power supply and zener current, (ICC + IZ): 30 mA; (3)Output current, source or sink, IO: 1.0 A; (4)Output energy (capacitive load per cycle), W: 5.0 μJ; (5)Current sense and voltage feedback inputs, Vin: - 0.3 to + 5.5 V; (6)Error amp output sink current, IO: 10 mA; (7)Power dissipation and thermal characteristics. D suffix, plastic package, SOIC-14 Case 751A Maximum power dissipation @ TA = 25°C,PD: 862 mW; Thermal resistance, junction-to-air: 145 °C/W; D1 suffix, plastic package, SOIC-8 case 751 maximum power dissipation @ TA = 25°C: 702 mW; Thermal resistance, junction-to-air: 178 °C/W; N suffix, plastic package, Case 626 maximum power dissipation @ TA = 25°C: 1.25 W; Thermal resistance, junction-to-air: 100 °C/W; (8)Operating junction temperature, TJ: +150 °C; (9)Operating ambient temperature: 0 to 70 °C; (10)Storage temperature range, Tstg: - 65 to +150 °C.

Features

UC3842BD1R2G features: (1)Trimmed oscillator for precise frequency control; (2)Oscillator frequency guaranteed at 250 kHz; (3)Current mode operation to 500 kHz; (4)Automatic feed forward compensation; (5)Latching PWM for cycle-by-cycle current limiting; (6)Internally trimmed reference with undervoltage lockout; (7)High current totem pole output; (8)Undervoltage lockout with hysteresis; (9)Low startup and operating current; (10)Pb-free packages are available.

Diagrams