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