THS3215 Datasheet, PDF (27/71 Pages) Texas Instruments – THS3215 650-MHz, Differential to Single-Ended DAC Output Amplifier

www.ti.com
THS3215
SBOS780A – MARCH 2016 – REVISED APRIL 2016
Feedthrough Measurement (continued)
In order to test the reverse feedthrough performance of the OPS in its disabled state, the circuit shown in
Figure 74 was used. The PATHSEL pin was driven high to select the external path to the OPS noninverting pin,
VIN+, pin 9. A 100-mV_PP, swept-frequency, sinusoidal signal was applied at the VIN+ pin and the output signal
was measured at the D2S output pin (VO1, pin 6). The results shown in Figure 58 account for the 16.5-dB loss
due to the D2S termination, and the test reports the reverse feedthrough between the VO1 and VIN+ pins. The
D2S inputs were grounded through 50-Ω resistors for this test.
16
15
14
50 k
1
100
x1
50 k
50
2 x1
49.9
+
250
500
3 x1
49.9
4
PATHSEL = High
5
6
7
VO1
169
13
12
18.5 k
11
162 Ÿ
249 Ÿ
18.5 k
DISABLE = High
10
VIN+
9
49.9
8
100
Network
Analyzer
GND Port 1
50
Port 2
50
73.2
Figure 74. Reverse-Feedthrough Test Circuit
Copyright © 2016, Texas Instruments Incorporated
Product Folder Links: THS3215
Submit Documentation Feedback
27