1. Design of an Instrumentation Amplifier

2. Instrumentation Amplifier Differential Pair with Active Load Bias Voltage Generation

3. Anatomy of a Different Pair with Active Load Differential Pair (Sec. 10.3) Differential Pair with Active Load (Sec. 10.3) Current Mirror (Section 9.2)

4. Bias Voltage Generation

5. Schedule Cascode (Section 9.1, 11/14) Current Mirror (Section 9.2.3, 11/19) Bias Circuitry (Handout, 11/26) Differential Pair (Section 10.3, 11/28) Differential Pair with Active Load (Section 10.6, 12/3) Instrumentation Amplifier (12/5)

6. Common Source Amplifier Design Design spec: 1 uA of bias current AV=-30 V/V of gain.

7. Measure Peak to Peak Voltage The gain is approximately 30.

8. Voltage Gain

9. Design Exploration Initial results – ro1=2.228 Mohms – ro2=5.32 Mohms – Av=-31.4 V/V – gmovergds1=44.57 – gmvoergds2=42.5 Design: If we can increase ro1, we can potentially raise the gain!

10. Cascode Circuit

11. Matlab Computation ro2 is 1.526 Mohms gmovergds_2=30 Mohms Rout is 55.2 Mohms

12. Gain Calculation We should be increase the gain from 30 to 97.

13. DC of Vout is too low! The gate bias voltage for T0=284.4 mV The gate bias voltage For T1 is 0.33 V +0.3 V 0.63 V The output voltage does Is only 71.87 mV What happens?

14. Calculate the Gain of a Circuit Using Norton Equivalent Circuit

15. Short Circuit Transconductrance

16. Sweep DC Voltage Define DC voltage as a variable. Copy from Cellview

17. Setup the Sweep

18. Run Parametric Analysis

19. Use Sweep to Zoom on the Correct Gate Bias Voltage We want to keep the output voltage close to 0.6 V.

20. Adjust Gate Voltage Gate voltage of T0: 255 mV Matlab: 284 mV We were off by 31 mV

21. Vin and Vout A faster way to calculate voltage gain is using the calculator. A gain of 88!

22. Using the Calculator

23. Calculate Peak to Peak Voltage