Microchip | MIC38HC43YM

The MIC38HC43YM is a part of MIC38HC4x family fixed frequency current-mode PWM controller with 1 A drive current capability. Micrel’s BiCMOS devices are pin-compatible with 384x bipolar devices. Their high output drive, with fast rise and fall times, combined with low startup current make it an ideal PWM controller where high efficiency is required.

Decreased output rise and fall times drive larger MOSFETs, and rail-to-rail output capability increases efficiency, especially at lower supply voltages. The MIC38HC43YM TR also features a trimmed oscillator discharge current and bandgap reference. MIC38HC4x-1 is available in 14-pin plastic DIP and SOIC packages. 8-pin devices feature small size, while 14-pin devices separate the analog and power connections for improved performance and power dissipation.

Features:

• Fast 20 ns output rise and 15 ns output fall times.
• –40°C to +85°C temperature range exceeds UC284x specifications.
• High-performance, low-power BiCMOS Process.
• Ultralow start-up current (50 μA typical).
• Low operating current (4 mA typical).
• High output drive (1 A peak current, HC version).
• CMOS outputs with rail-to-rail swing.
• Current-mode operation up to 500 kHz.
• Trimmed 5 V bandgap reference.
• Pin-for-pin compatible with UC3842/3843/3844/3845(A).
• Trimmed oscillator discharge current.
• UVLO with hysteresis.
• Low cross-conduction currents.

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