Features

• Wide V_IN Range: 4.5V to 60V (65V Abs Max)
• Wide Output Voltage Range: 0.8V ≤ V_OUT ≤ 99% • V_IN
• Adjustable Gate Drive Level 5V to 10V (OPTI-DRIVE)
• No External Bootstrap Diodes Required
• Low Operating I_Q: 29μA (One Channel On)
• Selectable Gate Drive UVLO Thresholds
• Out-of-Phase Operation Reduces Required Input Capacitance and Power Supply Induced Noise
• Phase-Lockable Frequency: 75kHz to 850kHz
• Selectable Continuous, Pulse Skipping or Low Ripple Burst Mode® Operation at Light Loads
• Selectable Current Limit (LTC3892/LTC3892-2)
• Very Low Dropout Operation: 99% Duty Cycle
• Power Good Output Voltage Monitors (LTC3892/LTC3892-2)
• Low Shutdown I_Q: 3.6μA
• Small 32-Lead 5mm × 5mm QFN Package (LTC3892/ LTC3892-2) or TSSOP Package (LTC3892-1)

Typical Application

Description

The LTC®3892/LTC3892-1/LTC3892-2 is a high performance dual step-down DC/DC switching regulator controller that drives all N-channel synchronous power MOSFET stages. Power loss and noise are minimized by operating the two controller output stages out-of-phase.

The gate drive voltage can be programmed from 5V to 10V to allow the use of logic or standard-level FETs and to maximize efficiency. Internal switches in the top gate drivers eliminate the need for external bootstrap diodes.

A wide 4.5V to 60V input supply range encompasses a wide range of intermediate bus voltages and battery chemistries. Output voltages up to 99% of V_IN can be regulated. OPTILOOP^® compensation allows the transient response and loop stability to be optimized over a wide range of output capacitance and ESR values.

The 29μA no-load quiescent current extends operating run time in battery powered systems. For a comparision of the LTC3892 to the LTC3892-1 and LTC3892-2, see Table 1 in the Pin Functions section of this data sheet.