60V+ Output Charge Pump Selection/Design

[Matt Coates]

I'm looking for some help in selecting a charge pump or other device for a project.

I have an input voltage VIN which can range from 17V to 52V, and from that I am generating a 12V rail using a COTS DC-DC module.

I also need to generate a voltage at VIN + 10V (or VIN + 12V would also work) which is then used to drive a HV op amp and FET gate. The current requirement is only 10mA or so.

I have been looking at the LTC3290 https://www.analog.com/en/products/ltc3290.html#product-overview which can happily generate VIN + 10V but my voltage input range is slightly too big. To keep within spec (VIN + VAUX < 55V) I would need to keep VIN below 43V. You can push it slightly whilst keeping below the Abs Max ratings, but this isn't ideal.

Does anyone have any suggestions for alternative approaches or parts? Any help would be much appreciated!

Thanks!

[Ian.M]

If you don't need the boosted Vin rail to come up before the 12V rail, simply use a 0.5W or 1W 12V output isolated DC-DC converter, powered from the 12V rail and stack its output on top of Vin.