MELZG 632: Analog IC Design Assignment 1 Submission Date: 18th August 2019 Note: Until and otherwise stated use the device data given in table at the end of this document and assume π½π«π« = π π½ where necessary. 1. Sketch πΌπ and transconductance of the transistor as a function of ππ for each circuit given as ππ varies from 0 to ππ·π· . 2. Sketch πππ’π‘ as a function of πππ for the circuit given as πππ varies from 0 to ππ·π· . 3. Sketch ππ and πΌπ as a function of time for the circuit given. The initial voltage of πΆ1 is equal to 3 V. 4. The transit frequency, ππ , of a MOSFET is defined as the frequency at which the small-signal current gain of the device drops to unity while the source and drain terminals are held at ac ground. Prove that ππ = ππ 2π(πΆπΊπ· + πΆπΊπ ) Note that ππ does not include the effect of S/D junction capacitance. 5. Explain why the structures cannot operate as current sources even if they are in saturation. 6. An NMOS device is operating in the subthreshold region has a ζ of 1.5. What variation in πΆπΊπ results in a ten-fold change in πΌπ· ? If πΌπ· = 10 µ π΄, what is ππ ?
