Title :
A chopper-based CMOS current sense instrumentation amplifier [for GSM]
Author :
Christoforou, Y.
Author_Institution :
Philips Semicond., Nijmegen, Netherlands
fDate :
6/24/1905 12:00:00 AM
Abstract :
We present in this paper a very low power, bipolar current sense chopper amplifier circuit, destinated to be used inside power management circuits for GSM applications. The role of the amplifier is to measure the current charging or discharging the battery of the cellular handset. This should allow an optimal use of the battery. For the reduction of the offset, the amplifier uses the chopper technique. The amplifier uses a resistor ratio to improve gain precision, needs a very small area 400 μm × 150 μm, consumes only 10 μA and exhibits a minimum residual offset of 15 μV for 16 kHz of chopper frequency.
Keywords :
CMOS analogue integrated circuits; cellular radio; choppers (circuits); feedback amplifiers; instrumentation amplifiers; low-power electronics; operational amplifiers; CMOS current sense; GSM applications; OTA; cellular handset; chopped offset; chopper-based amplifier circuit; current charging; current discharging; feedback; instrumentation amplifier; power management circuits; Battery charge measurement; Choppers; Circuits; Current measurement; Energy management; Frequency; GSM; Instruments; Resistors; Telephone sets;
Conference_Titel :
Instrumentation and Measurement Technology Conference, 2002. IMTC/2002. Proceedings of the 19th IEEE
Print_ISBN :
0-7803-7218-2
DOI :
10.1109/IMTC.2002.1006852
