I want to improve an existing OFF/ON circuit in a project I have. Why do most off/on controller ICs have such a high quiescent current (approx 6 uA)? Their sole purpose is to manage an off/on battery circuit. The transistor I currently use has leakage of 100 nA.
6uA typ or even 20 uA max is not much “power”.
The Maxim IC’s you selected are designed for 5V logic only/
If you need high voltage low Quiescent current switches, you can choose MOSFETs or BJT’s to suit your task and choose low side switching for logic level drive.
If you define all your specs, for input and output V,I etc. Then you can start your design rather than look at IC’s and ask why these do not do the undefined tasks in your project.
Specs 1st, (must haves and nice to have for all inputs, outputs and environment)
- then decide on topology, technology & find off-the-shelf solutions , figure out how it works,
- then decide , Make or Buy.
This is how design is done.
P.s. all transistors have tradeoffs for V limit vs hFE vs GBW vs power rating vs leakage current vs slew rate vs current limit or Ron.
That's probably mostly the output driver at work: it has to be able to still pull the output below 0.4 V even if you draw 1.6 mA from it. That'll require a transistor that sinks 1.6 mA – and assuming a current amplification of say \$\beta\approx 200\$ that would roughly lead to your numbers.