TA0310 Datasheet, PDF (9/14 Pages) STMicroelectronics – High Speed Operational Amplifiers for 75Ω Video Lines

Notes on video line driving
TA0310
Implementation of TSH7x-TSH8x-TSH9x-TSH11x families in dual supply -5V/+5V:
Figure 10: Implementation of the TSH7x-8x-9x-11x in dual supply -5V/+5V
1Vpp ^+5V
+
T_- SH
0Volt
Rg ^Rfb
-5V
1Vpp
2Vpp
video line
75Ω
75Ω
0Volt
1Vp-p
300mV
+5V
0V
-5V
Signal on the line
In this scenario, the implementation of the op-amp is much more simple because the video signal
amplitudes are far away from the rails. But the drawback of this solution is the cost of the providing a
power supply of -5V.
Note:Rfb can eMqual 1kΩ for TSH7x-8x-9x, 680Ω for TSH11x (see datasheet).
Frequency response of TSH7x-8x-9x-11x:
Figure 11: Small Signal Bandwidth. Gain=+2, Rload=150ohms
8
7
6
5
TSH7x-8x, 0/+5V
-3dB Bw = 48MHz
4
TSH11x, 0/+5V
-3dB Bw = 80MHz
TSH11x, -5/+5V
-3dB Bw = 110MHz
3
TSH7x-8x, -5V/+5V
-3dB Bw = 48MHz
2
1
TSH9x, -5V/+5V
-3dB Bw = 75MHz
0
1M
10M
100M
Frequency (Hz)
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