LTC3875 Series

Dual, 2-Phase, Synchronous Controller with Low Value DCR Sensing and Temperature Compensation

Catalog

Dual, 2-Phase, Synchronous Controller with Low Value DCR Sensing and Temperature Compensation

Part	Operating Temperature [Min]	Operating Temperature [Max]	Frequency - Switching [Max]	Frequency - Switching [Min]	Voltage - Supply (Vcc/Vdd) [Max]	Voltage - Supply (Vcc/Vdd) [Min]	Control Features	Topology	Output Phases	Number of Outputs	Mounting Type	Package / Case	Output Type	Output Configuration	Supplier Device Package	Function
Analog Devices LTC3875IUH#TRPBF	-40 °C	125 ¯C	720 kHz	250 kHz	38 V	4.5 V	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Buck	2	2	Surface Mount	40-WFQFN Exposed Pad	Transistor Driver	Positive	40-QFN (5x5)	Step-Down
Analog Devices LTC3875IUH#PBF	-40 °C	125 ¯C	720 kHz	250 kHz	38 V	4.5 V	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Buck	2	2	Surface Mount	40-WFQFN Exposed Pad	Transistor Driver	Positive	40-QFN (5x5)	Step-Down
Analog Devices LTC3875EUH#TRPBF	-40 °C	125 ¯C	720 kHz	250 kHz	38 V	4.5 V	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Buck	2	2	Surface Mount	40-WFQFN Exposed Pad	Transistor Driver	Positive	40-QFN (5x5)	Step-Down
Analog Devices LTC3875IUH#PBF	-40 °C	125 ¯C	720 kHz	250 kHz	38 V	4.5 V	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Buck	2	2	Surface Mount	40-WFQFN Exposed Pad	Transistor Driver	Positive	40-QFN (5x5)	Step-Down
Analog Devices LTC3875IUH	-40 °C	125 ¯C	720 kHz	250 kHz	38 V	4.5 V	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Buck	2	2	Surface Mount	40-WFQFN Exposed Pad	Transistor Driver	Positive	40-QFN (5x5)	Step-Down
Analog Devices LTC3875EUH#PBF	-40 °C	125 ¯C	720 kHz	250 kHz	38 V	4.5 V	Current Limit Enable Frequency Control Phase Control Power Good Soft Start Tracking	Buck	2	2	Surface Mount	40-WFQFN Exposed Pad	Transistor Driver	Positive	40-QFN (5x5)	Step-Down

Catalog

Dual, 2-Phase, Synchronous Controller with Low Value DCR Sensing and Temperature Compensation

Key Features

• Low Value DCR Current Sensing

• Programmable DCR Temperature Compensation

• ±0.5% 0.6V Output Voltage Accuracy

• Dual True Remote Sensing Differential Amplifiers

• Phase-Lockable Fixed Frequency 250kHz to 720kHz

• Dual, 180° Phased Controllers Reduce Required Input Capacitance and Power Supply Induced Noise

• Dual N-Channel MOSFET Synchronous Drive

• Wide VINRange: 4.5V to 38V Operation

• Output Voltage Range with Low DCR: 0.6V to 3.5V, without Low DCR: 0.6V to 5V

• Adjustable Soft-Start Current Ramping or Tracking

• Foldback Output Current Limiting

• Clock Input and Output for Up to 12-Phase Operation

• Short-Circuit Soft Recovery

• Output Overvoltage Protection

• Power Good Output Voltage Monitor

• 40-Lead QFN Packages

• AEC-Q100 Qualified for Automotive Applications

Description

The LTC3875 is a dual output current mode synchronous step-down DC/DC controller that drives all N-channel power MOSFET stages. It employs a unique architecture that enhances the signal-to-noise ratio of the current sense signal, allowing the use of very low DC resistance (DCR) power inductors to maximize efficiency in high current applications. This feature also reduces the switching jitter commonly found in low DCR applications with current mode control.The LTC3875 features two high speed differential amplifiers which can be used to compensate for the voltage drop from the LTC3875 to the load. Its DCR temperature compensated adjustable over current trip points from 10mV to 30mV limits the maximum output current precisely over temperature.A unique thermal balancing function adjusts per phase current to minimize the thermal stress for multichip single output applications. The LTC3875 is available in the 40- lead 6mm × 6mm (0.5mm pitch) and 40-lead 5mm × 5mm (0.4mm pitch) QFN packages.APPLICATIONSServers and InstrumentsTelecom SystemsDC Power Distribution Systems