LM7321, LM7322

www.ti.com

SNOSAW8E – MAY 2008 – REVISED SEPTEMBER 2015

10 Power Supply Recommendations

The use of supply decoupling is mandatory in most applications. As with most relatively high-speed or high-

output current op amps, best results are achieved when each supply line is decoupled with two capacitors; a

small value ceramic capacitor ( about 0.01

μF) placed very close to the supply lead in addition to a large value

Tantalum or Aluminum (> 4.7

μF). The large capacitor can be shared by more than one device if necessary. The

small ceramic capacitor maintains low supply impedance at high frequencies while the large capacitor will act as

the charge bucket for fast load current spikes at the op amp output. The combination of these capacitors will

provide supply decoupling and will help keep the op amp oscillation free under any load.

11 Layout

11.1 Layout Guidelines

Take care to minimize the loop area formed by the bypass capacitor connection between supply pins and

ground. A ground plane underneath the device is recommended; any bypass components to ground should have

a nearby via to the ground plane. The optimum bypass capacitor placement is closest to the corresponding

supply pin. Use of thicker traces from the bypass capacitors to the corresponding supply pins will lower the

power supply inductance and provide a more stable power supply.

The feedback components should be placed as close to the device as possible to minimize stray parasitics.

11.2 Layout Example

Figure 70. LM732xx Layout Example

Copyright © 2008–2015, Texas Instruments Incorporated

Submit Documentation Feedback

27

Product Folder Links: LM7321 LM7322