Power Supply La4out And By ass

The AD863xA family operates from either a single +2.3V to +5.5V supply or

dual ±1.15V to ±2.25V supplies. For single-supply operation, bypass the power supply

Application Notes

VS with a ceramic capacitor (i.e. 0.01μF to 0.1μF) which should be placed close

(within 2mm for good high frequency performance) to the VS pin. For dual-supply

operation, both the VS+ and the VS– supplies should be bypassed to ground with

separate 0.1μF ceramic capacitors. A bulk capacitor (i.e. 2.2μF or larger tantalum

capacitor) within 100mm to provide large, slow currents and better performance. This

bulk capacitor can be shared with other analog parts.

Good PC board layout techniques optimize performance by decreasing the

amount of stray capacitance at the op-amp’s inputs and output. To decrease stray

capacitance, minimize trace lengths and widths by placing external components as

close to the device as possible. Use surface-mount components whenever possible. For

the op-amp, soldering the part to the board directly is strongly recommended. Try to

keep the high frequency big current loop area small to minimize the EMI

(electromagnetic interfacing).

Grounding

A ground plane layer is important for the AD863xA circuit design. The length of

the current path speed currents in an inductive ground return will create an unwanted

voltage noise. Broad ground plane areas will reduce the parasitic inductance.

Input To Output Coupling

To minimize capacitive coupling, the input and output signal traces should not be

parallel. This helps reduce unwanted positive feedback.

480

μA, 6.5MHz, RRIO CMOS Operational Amplifiers

UMW

AD8631,AD8632,AD8634

R

www.umw-ic.com

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UTD Semiconductor Co.,Limited