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Switched capacitor question

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Mar 19, 2022
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I have a question concerning switched caps dc-dc converters. I want to test corners across load variations (from 1mA to 150 mA current consumed by load)
they told me to put a current mirror as a load but I am not sure how to put this CM at the Vout of my switched cap to make sure it consumes that current
Can someone help, please?

A current source by itself can do the job. Namely the conventional 2-transistor type. It's compatible with your low power specs.

The lefthand resistor biases the transistor and is important for setting maximum overall current through the system.

Righthand column...
Current level is set chiefly by the bottom resistor value. Set its value to admit a maximum desired current level. Then you can use a wide range of values for the upper resistor (load), yet maximum current reaches the same peak level.

To pass 1mA, change the bottom resistor to 600 ohms. A potentiometer makes it easy.

Current source 150mA supply 2-20V (2 NPN).png

--- Updated ---

Current mirror arranged in a manner that seems to work. The transistors must be NPN rather than PNP. Ampere levels are not identical in a strict sense although the righthand circuit has its separate lesser current flow which controls the left column's greater current flow.

The left column 'dummy' load can be a transistor. It carries your spec maximum current therefore it needs adequate power rating. Put a resistor or other type of load if desired in emitter or collector wire.

A lesser current level is feasible in the right hand column yet it controls the left column. You can vary righthand voltage or righthand resistor values. Low power ratings are suitable.

Current mirror at right controls load at left 140mA (2 NPN).png
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