UC2844B Datasheet | onsemi

feature an oscillator, a temperature pensated reference, high gain error amplifier, current sensing parator, 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, a latch for single pulse metering, and a flip- flop which blanks the output off every other oscillator cycle, allowing output deadtimes to be programmed from 50% to 70%. These devices are available in an 8- pin dual- in- line and surface mount (SOIC- 8) plastic package as well as the 14- pin plastic surface mount (SOIC- 14). The SOIC- 14 package has separate power and ground pins for the totem pole output stage. The UCX844B has UVLO thresholds of 16V (on) and 10V (off), ideally suited for off- line converters. The UCX845B is tailored for lower voltage applications having UVLO thresholds of 8.5V (on) and 7.6V (off). Features - Trimmed Oscillator for Precise Frequency Control - Oscillator Frequency Guaranteed at 250 k Hz - Current Mode Operation to 500 k Hz Output Switching Frequency - Output Deadtime Adjustable from 50% to 70% - Automatic Feed Forward pensation - Latching PWM for Cycle- By- Cycle Current Limiting - Internally Trimmed Reference with Undervoltage Lockout - High Current Totem Pole Output - Undervoltage Lockout with Hysteresis - Low Startup and Operating Current - These Devices are Pb- Free and are Ro HS pliant - NCV Prefix for Automotive and Other Applications Requiring Unique Site and Control Change Requirements; AEC- Q100 Qualified and PPAP Capable DATA SHEET .onsemi. 8 1 14 1 8 1 PDIP- 8 N SUFFIX CASE 626 SOIC- 14 D SUFFIX CASE 751A SOIC- 8 D1 SUFFIX CASE 751 PIN CONNECTIONS pensation 1 Voltage Feedback 2 8 Vref 7 VCC Current Sense 3 6 Output RT/CT 4 5 GN (Top View) pensation 1 NC 2 Voltage Feedback 3 NC 4 Current Sense 5 NC 6 RT/CT 7 14 Vref 13 NC 12 VCC 11 VC 10 Output 9 GND 8 Power Ground (Top View) ORDERING...