TS358 Taiwan Semiconductor Company, TS358 Datasheet - Page 5

• Manufacturer Part Number: TS358
• Description: Dual Operating Amplifier
• Manufacturer: Taiwan Semiconductor Company

REPRESENTATIVE CIRCUIT SCHEMATIC
CIRCUIT DESCRIPTION
The TS358 series made using two internally compensated,two-stage operational amplifiers.
The first stage of each consists of differential input devices Q20 and Q18 with input buffer
transistors Q21 and Q17 and differential to single ended converter Q3 and Q4. The first stage
performs not only the first stage gain function but also performs the level shifting and
transconductance reduction functions. By reducing the transconductance, a smaller compen-
sation capacitor (only 5.0pF) can be empllyed, thus saving chip area. The transconductance
reduction is accomplished by splitting the collectors of Q20 and Q18. Another feature of this
input stage is that the input common mode range can include the negative supply or ground, in
single supply operation, without saturating either the input devices or the differential to single-
ended converter. The second stage consists of a standard current source load amplifier stage.
Each amplifier is biased from an internal-voltage regulator which has a low temperature coeffi-
cient thus giving each amplifier good temperature chatacteristics as well as excellent power
supply rejection.
Inputs
Q2
Q18
Q17
Q3
Q19
Q4
5.0 pF
Q21
Q20
Q5
Q16
Q6
Q26
Q7
Q8
Q15
Q9
Q12
Q14
40k
25
Q13
Q1 1
Q10
Output
Q1
2.0k
Common to Both
Bias Circuitry
Q22
Q23
Q25
Amplifiers
2.4k
Q24
V
V
CC
EE
/Gnd