Rail-to-Rail经典分析

Rail-to-Rail Op AmpsAMSC/TAMU

Rail-to-Rail Op Amps

Edgar Sánchez-Sinencio TAMU, AMSC
Thanks to Shouli Yan for his valuable input in helping in generating part of this material 1

Op Amp Configurations
There are the following Op Amp Configurations, (a) inverting configuration, (b) non-inverting configuration, (c) voltage follower ( or voltage buffer, a special case of (b)), (d) fully-differential configuration, (e) fully-differential to single-ended conversion
R2 R1

vI vO
R1 R2

vO

vI

vO

vI
(a)

(b)

R2

(c)

vI+ R1 vI- R1

R2

vOR2

vI- R1

vO
R2

vO+ v I+ R1

(d)

(e)
2

Why Rail-to-Rail Differential Input Stage?
The input and output swing requirements
Configuration Inverting Non-inverting Voltage follower Fully Differential FD to SE Figure (a) (b) (c) (d) (e) Input common mode voltage swing ≈0 R1/(