manodipan wrote on Apr 30th, 2009, 4:57am:Hi guys,
I want an area efficient very high resistance(~ 4-5 MOhms) ,also the resiatnce is required to be controllable as i am using this to control the current source......off transistors can implement high resistance but process variation effect is very high...so can you suggest some literatures on that.....thank you..
Hi,
No matter how you realize an on-chip resistance, the process variation will be quite high as long as there is no external precise reference available. You have to live with atleast +/- 20-30% variation in most cases. Else, you must consider trimming.
For realizing high resistance, you can use a narrow MOS transistor.
Regards,
Vivek