Simplified Schematic

Application Tips

The LM6365 is stable for gains of 25 or greater. The LM6361

and LM6364, specified in separate datasheets, are compen-

sated versions of the LM6365. The LM6361 is unity-gain

stable, while the LM6364 is stable for gains as low as 5. The

LM6361, and LM6364 have the same high slew rate as the

LM6365, typically 300 V/µs.

To use the LM6365 for gains less than 25, a series

resistor-capacitor network should be added between the in-

put pins (as shown in the Typical Applications, Noise Gain

Compensation) so that the high-frequency noise gain rises

to at least 25.

Power supply bypassing will improve stability and transient

response of the LM6365, and is recommended for every de-

sign. 0.01 µF to 0.1 µF ceramic capacitors should be used

(from each supply “rail” to ground); an additional 2.2 µF to

10 µF (tantalum) may be required for extra noise reduction.

Keep all leads short to reduce stray capacitance and lead in-

ductance, and make sure ground paths are low-impedance,

especially where heavier currents will be flowing. Stray ca-

pacitance in the circuit layout can cause signal coupling be-

tween adjacent nodes, and can cause circuit gain to uninten-

tionally vary with frequency.

Breadboarded circuits will work best if they are built using

generic PC boards with a good ground plane. If the op amps

are used with sockets, as opposed to being soldered into the

circuit, the additional input capacitance may degrade circuit

performance.

Typical Applications

DS009152-3

Offset Voltage Adjustment

DS009152-11

Noise-Gain Compensation

DS009152-12

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