RF Micro Devices Inc.

7628 Thorndike Road, Greensboro, NC 27409-9421

DS140530

For sales or technical support, contact RFMD at +1.336.678.5570 or customerservice@rfmd.com.

The information in this publication is believed to be accurate. However, no responsibility is assumed by RF Micro Devices, Inc. ("RFMD") for its use, nor for any infringement of patents or other rights of

third parties resulting from its use. No license is granted by implication or otherwise under any patent or patent rights of RFMD. RFMD reserves the right to change component circuitry, recommended

application circuitry and specifications at any time without prior notice.

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RFAC3612

Application Guidelines

A decoupling capacitor on VDD may be used for noise reduction. The one directional 3-wire SPI compatible interface with chip select is a

very robust interface for on-board inter chip signaling. To further improve the robustness of the interface RFMD uses input level hysteresis

on the 3 logic inputs. This gives good immunity to noise on the input lines.

The PAC is DC coupled on RF1 and RF2 ports, with a bias voltage of 0V. This means that the RF ports can be DC shorted to GND, by

e.g. an inductor, but they cannot be connected to any other device with a non-zero bias voltage without a DC blocking capacitor.

Application Note

Turn On Sequence = VDD

Turn Off Sequence = RF

→ SPI → VDD

Branding Diagram