The PCI-Express is used in many PCs as the interface to the graphics card. Although the new format allows much higher data rate, one consequence is that 5V is no longer supplied to the interface. This has spawned a new generation of controller IC’s that use 12V for bias, and can also use 12V (or any lower voltage) for the input to the regulators. The ISL6549 can control one PWM and one linear output for these conditions, but it can also be used in other systems with 12V available. These EVAL boards provide a simple way to configure a system, and test it out.
There are two current ranges that are presently supported: ISL6549LOW-EVAL1 for higher output voltages, but lower output currents and ISL6549HI-EVAL1 for lower output voltages, but higher output currents. The schematic provided is for the generic board, so the values listed may not match each board; use the appropriate BOM for the correct values, and also for which components are populated or not (DNP = Do Not Populate).
- Single 12V bias supply (no 5V supply is required)
- Provides two regulated voltages
- Both controllers drive low cost N-Channel MOSFETs
- Small converter size
- Excellent output voltage regulation
- 12V down conversion
- PWM and linear output voltage range: down to 0.8V
- Simple single-loop voltage-mode PWM control design
- Fast PWM converter transient response
- Undervoltage fault monitoring on both outputs
- Processor and memory supplies
- ASIC power supplies
- Embedded processor and I/O supplies
- DSP supplies