Microchip Technology MIC38C43AYMM

Description
The MIC38C4xA family of BICMOS devices are fixed frequency, high performance, current-mode PWM controllers. They are pin compatible with 384x bipolar devices but offer several improvements.
Undervoltage lockout circuitry allows the '42 and '44 versions to start up at 14.5V and operate down to 9V, while the '43 and '45 versions start at 8.4V and operate down to 7.6V. All versions operate up to 20V.
Compared to bipolar 384x devices operating from a 15V supply, start-up current has been reduced to 50μA typical and operating current has been reduced to 4.0mA typical.
Decreased output rise and fall times drive larger MOSFETs, and rail-to-rail output capability increases efficiency, especially at lower supply voltages.
The MIC38C4xA also features a trimmed oscillator discharge current and bandgap reference.

Features
Fast 40ns output rise and 30ns output fall times (-40°C to 85°C temperature range meets UC284x specifications)
High-performance, low-power BICMOS Process
Ultralow start-up current (100µA typical)
Low operating current (4mA typical)
CMOS outputs with rail-to-rail swing
≥ 500kHz current-mode operation
Trimmed 5V bandgap reference
Pin-for-pin compatible with UC3842/3843/3844/3845
Trimmed oscillator discharge current
UVLO with hysteresis
Low cross-conduction current

Applications
Current-mode, off-line, switched-mode power supplies
Current-mode, dc-to-dc converters
Step-down "buck" regulators
Step-up "boost" regulators
Flyback, isolated regulators
Forward converters
Synchronous FET converters