hi there I want to learn how to make low power design

[nikhilele]

1>
First thing we should use CMOS instead of TTL
2>
enter in power down or idle mode will using microprocessor
3>
use Switching regulator specially when u want to decrease the voltage i.e buck regulator DC-DC convertor.
4>
use LP series of opams

what else I want to design my products such that they can operate using batteries for years.

 

[PaulHolland]

Hi, If you design something that has to work for years on battery you have to look deap itto the idle current consumption and NOT the operation current consumption. So do all that is possible to lower the first !!.

1: Use FET's & MOSFET's instead of transistors (NPN/PNP) (much lower idle current)
2: Use Microchip MPU's if needed or 74HC (NOT 74HCT) SERIES. good MCU is 12F629 series: 1nA Idle current.
3: If microchip MPU use the WDT to wake-up from sleep when needed !.
4: Select the correct battery technology: Alkaline has leak currents of 10 - 15 uA. 30% is gone after 3 years Ilde. Litium is Much better +/- 100nA leak current, 10 years for 20% loss !!.

5: Use you logic to switch on/off power consuming parts.
6: Make your design so that it can work without voltage regulators, no switched or linear.
7: Do not use Elco's but polyester of ceremic capacitors.
8: Do not use zener diodes.
9: Try to minimize OPAMPS or switch power off when not needed.

I have designed battery devices that can last 8 years on 1 3 Volt litium cell and operate 15 times a Day for 20 seconds transmitting IR data !!!!!!.

Paul.

 

[andrabi]

and yeah to add to the existing ponts..
i..u can use gated clocks..
ii..use high vt Mos to minimise leakage
iii..and spread the ciruits horintally rather than vertically e.g avoid usin cascodes instead use opam for high impedance that cascodes provide