what we’re trying to do is charge/discharge a single UltraCap cell (10, 25, or 50F). We were looking for a bidirectional DC/DC converter IC that will work with a constant output voltage equal to Li-ion battery, somewhere between 3.6 and 4.2V. However we are more than glad to look into two unidirectional components, one path for charge, one path for discharge.
We want to discharge UltraCap with max 800mA (at DC/DC output, that is, constant 4.2V), charge with maybe 200mA (again at the constant 4.2V side). We are flexible on charge current and can discuss if it helps. The 800mA discharge current is peak and expected to last 1ms, continuous current in the 300mA range.
Components like the BQ33100 seem to have functions (like cell balancing) we don’t need. We definitely overshot with the LTC3110EUF. We are not looking for all that functionality, and pricing has become a significant issue.
