General Description
The MIC2155 and MIC2156 are a family of two-phase, single-output synchronous buck control ICs featuring small size, high efficiency, and a high level of flexibility. The ICs implement a 500kHz (MIC2155) and 300kHz (MIC2156) voltage mode PWM control, with the outputs switching 180° out of phase. The result of the out-of-phase operation is 1MHz (or 600kHz) input ripple with ripple current cancellation, minimizing the required input filter capacitance. A 1% output voltage tolerance allows the maximum level of system performance. Internal drivers with adaptive gate drive allow the highest efficiency with the minimum external components.

Features
• Synchronous buck control ICs with outputs switching 180° out-of-phase
• Remote sensing with internal differential amplifier
• 4.5V to 14.5V input voltage range
• Adjustable output voltages down to 0.7V
• 1% output voltage accuracy
• Starts up into a pre-biased output
• 500kHz PWM operation (MIC2155)
• 300kHz PWM operation (MIC2156)
• Adaptive gate drive allows efficiencies over 95%
• Adjustable current limit with no sense resistor
• Senses low-side MOSFET current
• Internal drivers allow 25A per phase
• Power Good output allow simple sequencing
• Dual enables with micro-power shutdown and UVLO
• Programmable soft-start pin
• Output over-voltage protection
• Works with ceramic output capacitors
• Multi-input supply capability
• Single-output high-current capability with master/slave current sharing
• External synchronization
• Small footprint 32-pin 5mm × 5mm MLF®
• Junction temperature range of -40°C to +125°C

Applications
• Multi-output power supplies with sequencing
• DSP, FPGA, CPU and ASIC power supplies
• DSL modems
• Telecom and networking equipment
• Servers