PWM DC/DC Controller with VID Inputs for Portable GPU Core-Voltage Regulator

The ISL95870, ISL95870A, ISL95870B ICs are Single-Phase Synchronous-Buck PWM regulators

featuring Intersil’s proprietary R4 Technology™. The wide 3.3V to 25V input voltage range is ideal for systems that run on battery or AC-adapter power sources.

Features

• Input Voltage Range: 3.3V to 25V

• Output Voltage Range: 0.5V to 5V

• Precision Regulation

- Proprietary R4™ Frequency Control Loop

- ±0.5 System Accuracy Over -10°C to +100°C

• Optimal Transient Response

- Intersil’s R4™ Modulator Technology

• Output Remote Sense

• Extremely Flexible Output Voltage Programmability

- 2-Bit VID Selects Four Independent Setpoint Voltages for ISL95870B

- 2-Bit VID Selects Four Dependent or Three Independent Setpoint Voltages for ISL95870A

- Simple Resistor Programming of Setpoint Voltages

• Selectable 300kHz, 500kHz, 600kHz or 1MHz PWM Frequency in Continuous Conduction

• Automatic Diode Emulation Mode for Highest Efficiency

• Power-Good Monitor for Soft-Start and Fault Detection

Applications*(see page 26)

• Mobile PC Graphical Processing Unit VCC Rail

• Mobile PC I/O Controller Hub (ICH) VCC Rail

• Mobile PC Memory Controller Hub (GMCH) VCC Rail