UC3842A

UC1842A, UC1843A, UC1844A, UC1845A UC2842A, UC2843A, UC2844A, UC2845A UC3842A, UC3843A, UC3844A, UC3845A SLUS224G – SEPTEMBER 1994 – REVISED JULY 2022 UCx84xA Current-Mode PWM Controller 1 Features Optimized for Off-Line and DC-DC Converters Low Start-Up Current (< 0.5 mA) Trimmed Oscillator Discharge Current Automatic Feedforward Compensation Pulse-by-Pulse Current Limiting Enhanced Load Response Characteristics Undervoltage Lockout With Hysteresis Double Pulse Suppression High-Current Totem Pole Output Internally-Trimmed Bandgap Reference Up to 500-kHz Operation Create a Custom Design Using the UCx84xA With the WEBENCH® Power Designer 2 Applications Switch Mode Power Supplies (SMPS) DC-DC Converters Power Modules Industrial PSU Battery Operated PSU 3 Description The UCx84xA family of control devices is a pin-for-pin compatible improved version of the UCx84x family. Providing the necessary features to control currentmode or switched-mode power supplies, this family of devices has many improved features: startup current is less than 0.5 mA, oscillator discharge is trimmed to 8.3 mA, and during UVLO, the output stage can sink at least 10 mA at less than 1.2 V for VCC over 5 V. Device Information(1) PART NUMBER PACKAGE BODY SIZE (NOM) UC1842A, UC1843A, UC1844A, UC1845A CDIP (8) LCCC (20) 6.67 mm × 9.60 mm 8.89 mm × 8.89 mm UC2843A PLCC (20) 8.96 mm × 8.96 mm UC2842A, UC2843A, UC2844A, UC2845A, UC3842A, UC3843A, UC3844A, UC3845A PD...