Datasheet
TP2 TP3
C
3
0.1 Fm
C603 C0805
C
5
0.1 Fm
C
8
10 Fm
C
7
10 Fm
V
S-
J4
V
S-
C
12
0.1 Fm
C603C0805
C
11
0.1 Fm
C
9
10 Fm
C
10
10 Fm
V
S+
V
S+
J8
V
S+
C
15
Open
C
16
Open
C
13
Open
C
14
Open
V
S-
J5
GND
R
1
R
2
R
12
1kW
R
13
1kW
R
14
1kW
R
15
1kW
R
25
0W
J9
J10
R
26
R
16
487W
R
20
52.3W
R
17
487W
R
22
2
1
3
5
6
4
R
21
R
7
5
4
6
2
3
1
R
3
R
4
0W
R
6
49.9W
C
1
0.22 Fm
R
8
C
2
C
4
0.22 Fm
V
S-
V
S-
V
S+
R
23
R
18
R
24
0W
R
9
R
5
0W
R
10
52.3W
R
11
52.3W
J6
R
19
J7
J1
J2
T2T1
TP1
V
OUT+
V
OUT-
4
5
6
3
1
8
7
2
PW
CM
J11
JP1
J3
C
6
0.22 Fm
THS4521
THS4522
THS4524
SBOS458F –DECEMBER 2008–REVISED SEPTEMBER 2011
www.ti.com
EVM AND LAYOUT RECOMMENDATIONS
Figure 87 shows the THS4521EVM schematic. PCB layers 1 through 4 are shown in Figure 88; Table 8 lists the
bill of materials for the THS4521EVM as supplied from TI. It is recommended to follow the layout of the external
components near to the amplifier, ground plane construction, and power routing as closely as possible. Follow
these general guidelines:
1. Signal routing should be direct and as short as possible into and out of the op amp circuit.
2. The feedback path should be short and direct.
3. Ground or power planes should be removed from directly under the amplifier input and output pins.
4. An output resistor is recommended in each output lead, placed as near to the output pins as possible.
5. Two 0.1-μF power-supply decoupling capacitors should be placed as near to the power-supply pins as
possible.
6. Two 10-μF power-supply decoupling capacitors should be placed within 1 inch of the device and can be
shared among multple analog devices.
7. A 0.22-μF capacitor should be placed between the V
OCM
input pin and ground near to the pin. This capacitor
limits noise coupled into the pin.
8. The PD pin uses TTL logic levels; a bypass capacitor is not necessary if actively driven, but can be used for
robustness in noisy environments whether driven or not.
9. If input termination resistors R
10
and R
11
are used, a single point connection to ground on L2 is
recommended.
Figure 87. THS4521EVM: Schematic
36 Submit Documentation Feedback Copyright © 2008–2011, Texas Instruments Incorporated
Product Folder Link(s): THS4521 THS4522 THS4524