Analog Devices LTC7802-3.3

Description

The LTCR7802-3.3 is a high performance dual step-down synchronous DC/DC switching regulator controller that drives all N-channel power MOSFET stages. Constant frequency current mode architecture allows a phase-lockable switching frequency of up to 3MHz. The LTC7802-3.3 operates from a wide 4.5V to 40V input supply range. Power loss and supply noise are minimized by operating the two controller output stages out-of-phase. The very low no-load quiescent current extends operating runtime in battery powered systems. OPTI-LOOP compensation allows the transient response to be optimized over a wide range of output capacitance and ESR values. The LTC7802-3.3 features a precision 0.8V reference and power good output indicators. The MODE pin selects among Burst Mode operation, pulse-skipping mode, or continuous inductor current mode at light loads. The LTC7802-3.3 additionally features spread spectrum operation which significantly reduces the peak radiated and conducted noise on both the input and output supplies, making it easier to comply with electromagnetic interference (EMI) standards.

Features

• Wide Input Voltage Range: 4.5V to 40V
• Wide Output Voltage Range: 0.8V to 99% - VIN
• Low Operating IQ: 12μA (14V to 3.3V, Channel 1 On)
• Fixed 3.3V Output Voltage on Channel 1
• Spread Spectrum Operation
• RSENSE or DCR Current Sensing
• Out-of-Phase Controllers Reduce Required Input Capacitance and Power Supply Induced Noise
• Programmable Fixed Frequency (100kHz to 3MHz)
• Phase-Lockable Frequency (100kHz to 3MHz)
• Selectable Continuous, Pulse-Skipping, or Low Ripple, Burst ModeR Operation at Light Loads
• Very Low Dropout Operation: 99% Duty Cycle
• Power Good Output Voltage Monitors
• Output Overvoltage Protection
• Internal LDO Powers Gate Drive from VIN or EXTVCC
• Low Shutdown IQ: 1.5μA
• Side Wettable 4mm × 5mm QFN-28 Package

Typical applications

• Automotive and Transportation
• Military / Avionics
• Industrial

More information

• Datasheet
• IC product information