Title :
A 16-bit current sample/hold circuit using a digital CMOS process
Author :
Mehr, Iuri ; Sculley, Terry
Author_Institution :
Dept. of Electr. Eng. & Comput. Sci., Washington State Univ., Pullman, WA, USA
fDate :
30 May-2 Jun 1994
Abstract :
In current-mode circuits clock feedthrough from sampling switches is a major source of error. While this error can be reduced to only an offset in switched-capacitor circuits, it produces more severe nonlinearities in switched-current designs. If the input is held constant over several cycles, clock feedthrough errors can be significantly reduced, but for a dynamic input, the ultimate solution has been to use a large sampling capacitor and small-switches. We propose a method of building a highly accurate oversampling current-mode sample/hold circuit using feedback architectures. First, second, and third-order feedback structures are proposed and simulated, with the results showing increased precision as oversampling ratio increases. A 16-bit current sample/hold circuit using a standard digital 2 μm CMOS process is presently being designed and fabricated
Keywords :
CMOS digital integrated circuits; circuit feedback; sample and hold circuits; switched current circuits; 16 bit; 2 micron; clock feedthrough errors; current-mode circuit; digital CMOS process; feedback; nonlinearities; oversampling; sample/hold circuit; simulation; switched-current circuit; Buildings; CMOS process; Circuit simulation; Clocks; Current mode circuits; Feedback circuits; Sampling methods; Switched capacitor circuits; Switches; Switching circuits;
Conference_Titel :
Circuits and Systems, 1994. ISCAS '94., 1994 IEEE International Symposium on
Conference_Location :
London
Print_ISBN :
0-7803-1915-X
DOI :
10.1109/ISCAS.1994.409397