Pergunta de entrevista da empresa Broadcom

how to bias a cascode current mirror? how you would layout it?

Respostas da entrevista

Sigiloso

12 de fev. de 2018

- Biasing the gate of the cascode devices with a ratio of 1/5 or 1/6 (W/L) to ensure the lower device stay in saturation. If we have a ratio lower than 1/6, then we are decreasing the minimum Vo for the cascode device. - The 1/5 (W/L) device while having a long channel, its better to layout it with 5 (W/L) transistors connected in series. Why? to decrease the variation of Vt of long channel transistors

Sigiloso

10 de mai. de 2019

Mirroring transistors has to be matched and interdigitized to reduce 2nd order effects. Using multiplier matches the transistor better.