You should use a switching regulator to minimize losses. At 175W, you could use a PWM chip like UC384X or a microcontroller driving a MOSFET in "buck" configuration. Then, use voltage feedback from the output to maintain a constant output voltage. The feedback loop should be adjusted as required. You could also use a ready made buck controller.
You should use a switching regulator to minimize losses. At 175W, you could use a PWM chip like UC384X or a microcontroller driving a MOSFET in "buck" configuration. Then, use voltage feedback from the output to maintain a constant output voltage. The feedback loop should be adjusted as required. You could also use a ready made buck controller.
You can use UC3843. Download the datasheet and study the datasheet to understand how it works and how to use it. You can read associated application notes if that helps. Then, read a bit about buck converters and high-side drivers. Shouldn't be too hard to understand. Then look for such circuits or you can even design one yourself. You need:
1) UC3843 set up as high frequency oscillator.
2) UC3843 drives a high-side MOSFET driver like IR2117. The IR2117 drives the MOSFET in a buck configuration.
3) Filter the output with appropriate LC filter.
4) UC3843 "monitors" the output via a feedback circuitry to ensure that output stays fixed.
5) You will need an auxiliary power supply to power the UC3843 and the IR2117.
You can read about buck converters here: **broken link removed**
You can get help for buck converter design here: **broken link removed**
Here is an application note for UC384X: www.soloelectronica.net/PDF/AppNote03.pdf