RT8857

4/3/2/1-Phase PWM Controller with Embedded Drivers for CPU Core Power Supply

The RT8857 is a 4/3/2/1-phase synchronous buck controller with 2 integrated MOSFET drivers for Intel VR11.1/VR10.x and AMD K8/K8_M2 CPUs power application. The RT8857 uses differential inductor DCR current sense to achieve phase current balance and active voltage positioning. Other features include adjustable operating frequency, adjustable soft start, power good indication, external error-amp compensation, over voltage protection, over current protection, VRHOT sensing and IMON for various applications. The RT8857 comes to a small footprint with WQFN-48L 7x7 package.

Applications

Desktop CPU Core Power
Low Voltage, High Current DC/ DC Converter

Key Spec.
	RT8857
Status	Active
VID Table Support	K8;K8_M2;VR10.x;VR11.1
Number of Phases	4
Vcc (typ) (V)	12
Vin (min) (V)	10.8
Vin (max) (V)	13.2
Accuracy (Vout>=1V) (+/- %)	0.5
Freq (typ) (kHz)	300
Built-in DAC Generator	Yes
Number of MOSFET Drivers	2
Features	Adjustable Current Limit;Adjustable Frequency;Adjustable Soft-Start;Built-in Bootstrap Switch;Current Mode Control;Cycle-by-Cycle Current Limit;DCR Current Sense;Diode Emulation Mode;Droop Control;Enable Input;Fast Transient Response;OVP;Power Good;SCP;UVP
Package Type	WQFN7x7-48

Features

12V Power Supply Voltage
4/3/2/1-Phase Power Conversion
2 Embedded MOSFET Drivers
Internal Regulated 5V Output
VID table for INTEL VR11.1/VR10.x and AMD K8/K8_M2 CPUs
Continuous Differential Inductor DCR Current Sense
Adjustable Soft Start
Adjustable Frequency
Power Good Indication
Adjustable Over Current Protection
Over Voltage Protection
VRHOT Sensing with External Thermistor
IMON Output Current Indication
Power State Indicator (PSI)
Small 48-Lead WQFN Package
RoHS Compliant and Halogen Free

Datasheet
Title	Last Update	Download
4/3/2/1-Phase PWM Controller with Embedded Drivers for CPU Core Power Supply	2018/06/08

Please confirm with our distributor or sales representative for actual stock status.