TS616 STMicroelectronics, TS616 Datasheet - Page 29

• Manufacturer Part Number: TS616
• Description: Multi video line driver (6 lines) and ADSL driver
• Manufacturer: STMicroelectronics

Specifications of TS616

• Low Noise: 2.5nV/√Hz
• High Output Current: 420mA
• High Slew Rate: 420V/µs
• -3db Bandwidth: 40MHz @ gain = 12dB on 25

TS616
9.1
9.2
The bias of an inverting amplifier
A resistance is necessary to achieve good input biasing, such as resistance R, shown in
Figure
The magnitude of this resistance is calculated by assuming the negative and positive input
bias current. The aim is to compensate for the offset bias current, which could affect the
input offset voltage and the output DC component. Assuming Ib-, Ib+, R
volt output, the resistance R is:
Figure 66. Compensation of the input bias current
Active filtering
Figure 67. Low-pass active filtering - Sallen-Key
From the resistors R
inverting amplification configuration:
We assume the following expression as the response of the system:
R = R
66.
in
// R
fb
fb
IN
IN
and R
Ib-
Ib-
R
R
G,
1
1
we can directly calculate the gain of the filter in a classic non-
T
j
R
R
Ib+
Ib+
in
in
=
R
R
Vout
---------------- -
A
2
2
Vin
R
R
V
_
_
+
+
j
=
j
R
R
TS616
TS616
G
G
g
C
C
=
C
C
1
1
2
2
=
R
R
Vcc+
Vcc+
Vcc-
Vcc-
---------------------------------------- -
1
fb
fb
1
+
+
+
+
_
_
2
R
--------
R
TS616
TS616
---- -
j
fb
910
910
g
g
c
R
R
+
fb
fb
Output
Output
----------- -
j
c
2
Load
Load
Choosing the feedback circuit
2
OUT
OUT
25
25
in
, R
fb
and a zero
29/37