The CosmicPi project uses a very nice chip for biasing SiPMs, the MAX1932. It can be configured to output as much as 90V for powering SiPMs, and you can set the voltage within a programmable range using SPI. It’s not cheap, but it’s very cool.

The jumpers (O1 and O2) allow two output ranges: 25.5V..30.5V for Onsemi SiPMs, or 36.5V..48.5V for Broadcom ones.

The board works great for powering the SiPMs, but draws a bit more current than I'd be happy with, at ~9mA while supplying 31V. I certainly did not help with the feedback resistors that can draw up to 150uA @ 31V. Adding reverse current through diode, switching efficiency (0.5 hinted in the datasheet), and the 1mA operating supply current I'd expect about 4mA. Interestingly even with the chip in shutdown (DAC = 0x00) I'm seeing ~3mA being drawn.

But it's definitely good enough to allow me to develop the analog front-end for the SiPM which plugs into the horizontal headers on the PCB.