CMOS基本放大器设计°ò MOSFET¤j 1. 2. 3. °q]-pP¤R °òMOSFET¤j IC MOSFET¤j 8-22¤¤z ]¤Z °q]-pP¤R Discrete MOSFET amplifiers°]-p 1. 2. 3. ]° IG=0A qe ]-pC IDM VGSA¤p ¤]-pC RGq±`¤jb Mδ ≥∫Χβ ICs{í AG°]-p bIC]-p¤¤¤¤¨C 8-23¤¤z ]¤Z IC MOSFET amplifiers°]-p ICq°]-p¤@¨°ò-ìhG 1. 2. ¤qAhqéAC§Y active loadC ¨qyC qy¤@¨G¤@Oe-±¨ìLF¤óA±N GSuFt¤@ O¨qyè (current mirror)C °òMOSqyè 1 I REF IREF¨Mw VGS C 1 W ′ (VGS Vt ) 2 = kn 2 L 1 3 IO = VGS¨Mw IOC 1 W ′ (VGS Vt )2 kn 2 L 2 2 VGS A -Y¤]b P°òOPs§@A Vt¤] PA k’¤]PAפ]PC Q1M Q2P IO I REF = (W / L)2 (W / L)1 ο∞ι∞Η±±±ο∩ΤΧ 8-24¤¤z ]¤Z qyèéXS IO IREF Slope=1/ro For Q1 and Q2 are matched. VGS -Vt í VGS VO VO ≥VGS -Vt¤§q ¤p°T IO Ro Ro = VO V = ro 2 = A IO I O Ro 8-25¤¤z ]¤Z qyè]-p I D1 = I D1 = 1 W ′ (VGS Vt ) 2 kn 2 L 1 VDD VGS R ID……