ISL6539 Wide Input Range Dual PWM Controller with DDR Option

VIN (min) (V)	3.3
VIN (max) (V)	18
VOUT (min) (V)	0.9
VOUT (max) (V)	5.5
IOUT (max) (A)	8

The ISL6539 dual PWM controller delivers high efficiency and tight regulation from two voltage regulating synchronous buck DC/DC converters. It was designed especially for DDR DRAM, SDRAM, graphic chipset applications, and system regulators in high performance applications.

Voltage-feed-forward ramp modulation, current mode control, and internal feedback compensation provide fast response to input voltage and output load transients. Input current ripple is minimized by channel-to-channel PWM phase shift of 0°, 90°, or 180° (determined by input voltage and status of the DDR pin).

The ISL6539 can control two independent output voltages adjustable from 0.9V to 5.5V or, by activating the DDR pin, transform into a complete DDR memory power supply solution. In DDR mode, CH2 output voltage VTT tracks CH1 output voltage VDDQ. CH2 output can both source and sink current, an essential power supply feature for DDR memory. The reference voltage VREF required by DDR memory is generated as well.

In dual power supply applications the ISL6539 monitors the output voltage of both CH1 and CH2. An independent PGOOD (power good) signal is asserted for each channel after the soft-start sequence has completed, and the output voltage is within PGOOD window. In DDR mode CH1 generates the only PGOOD signal.

Built-in overvoltage protection prevents the output from going above 115% of the set point by holding the lower MOSFET on and the upper MOSFET off. When the output voltage decays below the overvoltage threshold, normal operation automatically resumes. Once the soft-start sequence has completed, undervoltage protection latches the offending channel off if the output drops below 75% of its set point value for the dual switcher. Adjustable overcurrent protection (OCP) monitors the voltage drop across the rDS(ON) of the lower MOSFET. If more precise current-sensing is required, an external current sense resistor may be used.

ISL6539 特点

Provides regulated output voltage in the range 0.9V-5.5V
Complete DDR memory power solution with VTT tracks VDDQ/2 and VDDQ/2 buffered reference output
Supports both DDR-I and DDR2 memory
Lossless rDS(ON) current-sense sensing
Excellent dynamic response with voltage feed-forward and current mode control accommodating wide range LC filter selections
Dual mode operation–operates directly from a 5.0-15V input or 3.3V/5V system rail
Undervoltage lock-out on VCC pin
Power-good, overcurrent, overvoltage, undervoltage protection for both channels
Synchronized 300kHz PWM operation in PWM mode
Pb-Free Plus Anneal Available (RoHS Compliant)

ISL6539 应用

Single and Dual Channel DDR Memory Power Systems
Graphics cards - GPU and memory supplies
Supplies for Servers, Motherboards, FPGAs
ASIC power supplies
Embedded processor and I/O supplies
DSP supplies

ISL6539 芯片订购指南

芯片型号	产品状态	温度范围	封装尺寸图	潮湿敏感度等级MSL	美元价格US $
ISL6539CAZ	量产	民用级	28 Ld QSOP	2	2.05
ISL6539CAZ-T	量产	民用级	28 Ld QSOP T+R	2	2.05
ISL6539EVAL1	量产		评估板	N/A	价格录入中
ISL6539EVAL2	量产		评估板	N/A	价格录入中
ISL6539IAZ	量产	工业级	28 Ld QSOP	3	2.71
ISL6539IAZ-T	量产	工业级	28 Ld QSOP T+R	3	2.71
ISL6539IRZ	Coming Soon	工业级	28 Ld QFN	2	价格录入中
ISL6539IRZ-T	Coming Soon	工业级	28 Ld QFN T+R	2	价格录入中
ISL6539CA	停产	民用级	28 Ld QSOP	2	N/A
ISL6539CA-T	停产	民用级	28 Ld QSOP T+R	2	N/A
ISL6539IA-T	停产	工业级	28 Ld QSOP T+R	2	N/A
ISL6539IA	To Be Discontinued	工业级	28 Ld QSOP	2	3.24