Measuring Leakage current in a Big Schematic using XA/HSPICE/HSIM

*Set accuracy level to 6

.option xa_cmd="set_sim_level 6"

*Doing operating point analysis

.op

*Optional, but good to have a probe point – helpful if the XA run takes a lot of time to run

.probe i(vvdd) i(vgnd)

*Can measure the ‘transient’ current through VDD – that’s leakage current (if no other nodes are switching)

.meas tran vdd_cur i(vvdd)

Analog Filters - Pease

Various Basic Filter (Passive) Designs

Time domain and Freq domain response

A better response in frequency domain has a lousy time-domain response and vice-versa ..

a) a sharp roll-off i.e. small transition band filter rings in the time domain

b) while a relatively gradual roll-off has a more flat step response

High Q Filters

High Q + High Precision: NOT POSSIBLE !!

if someone manages to build one with high Q and high precision, the circuit rings forever and never settles ..

Passive and Active Filters

Passive Filters: R, L, C: Use more Area
Active Filters: Using transistors, OPAMPS: Burn more Power

Designing Analog Filters

Talk by Robert A. Pease: 05/27/2008, Department of Electrical Engineering, Stanford, CA

Useful links: http://www.national.com/rap/
Webench Filters: http://www.national.com/appinfo/amps/webench_filters.html

Williams, A. and F.J. Taylor, Electronic Filter Design Handbook, MGH, NY 2006