Rev C Preliminary

Amalfi Confidential

Page 11

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Preliminary Device Specification

AM7808

Timing and VRAMP Profile

VRAMP

ENABLE,

SW1

Time Mask

Up-ramp

TX_EN

10 us

10 us

8 us

Time Mask

Down-ramp

10 us

10 us

8 us

0.16V

Less than

0.18V

ENABLE: Set high to enable TXM

SW1: Set low or high depending on Band

RF Input

Power

Figure 1. AM7808 Timing Diagram for VRAMP, TX_EN, SW1 and ENABLE.

Note on Pedestal Voltage: The VRAMP profile should set the pedestal voltage at the nominal value prior to the onset of

the ramp-up to ensure that the output power tracks the VRAMP control voltage. The nominal value has been optimized

to ensure good performance over the entire dynamic power range of the amplifier.

For information of power calibration and VRAMP profiles, see separate application notes.

Note on the Down-Ramp: The trailing edge of the VRAMP waveform should be brought down as low as the TCVR/base

band allows, typically 0.10V before TX_EN, ENABLE and SW1 are set low to minimize spurious emissions from being

generated.