Consider the Wilson MOS mirror of Fig. 8.41(a) for the case of all transistors

Chapter 8, Problem 8.88

(choose chapter or problem)

Consider the Wilson MOS mirror of Fig. 8.41(a) for the case of all transistors identical, with W/L = 10, nCox = 400 A/V2 , Vt n = 0.5 V, and VA = 18 V. The mirror is fed with IREF = 180 A. (a) Obtain an estimate of VOV and VGS at which the three transistors are operating, by neglecting the Early effect. (b) Noting thatQ1 andQ2 are operating at differentVDS , obtain an approximate value for the difference in their currents and hence determine IO. (c) To eliminate the systematic error between IO and IREF caused by the difference in VDS between Q1 and Q2, a diode-connected transistor Q4 can be added to the circuit as shown in Fig. 8.41(c). What do you estimate IO now to be? (d) What is the minimum allowable voltage at the output node of the mirror? (e) Convince yourself that Q4 will have no effect on the output resistance of the mirror. Find Ro. (f) What is the change in IO (both absolute value and percentage) that results from VO = 1 V?

Unfortunately, we don't have that question answered yet. But you can get it answered in just 5 hours by Logging in or Becoming a subscriber.

Becoming a subscriber
Or look for another answer

×

Login

Login or Sign up for access to all of our study tools and educational content!

Forgot password?
Register Now

×

Register

Sign up for access to all content on our site!

Or login if you already have an account

×

Reset password

If you have an active account we’ll send you an e-mail for password recovery

Or login if you have your password back