2.4GHz 802.11b Zero-IF Transceivers

14

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Pin Description (continued)

PIN

NAME

DESCRIPTION

39

RX_BBQP

Receive Positive Quadrature Baseband Output. Analog low-impedance differential buffer output.

Connect output directly to baseband ADC input. Internally biased to 1.2V common-mode voltage and

can drive loads up to 5k

Ω || 5pF.

40

RX_BBQN

Receive Negative Quadrature Baseband Output. Analog low-impedance differential buffer output.

Connect output directly to baseband ADC input. Internally biased to 1.2V common-mode voltage and

can drive loads up to 5k

Ω || 5pF.

41

RX_BBIN

Receive Negative In-Phase Baseband Output. Analog low-impedance differential buffer output.

Connect output directly to baseband ADC input. Internally biased to 1.2V common-mode voltage and

can drive loads up to 5k

Ω || 5pF.

42

RX_BBIP

Receive Positive In-Phase Baseband Output. Analog low-impedance differential buffer output.

Connect output directly to baseband ADC input. Internally biased to 1.2V and can drive loads up to

5k

Ω || 5pF.

43

RX_DET

Receive Level Detection Output. Digital CMOS output. Connect output directly to baseband IC input.

Used to indicate RF input level. Logic high for input levels above -49dBm (typ). Logic low for levels

below -54dBm (typ).

44

VCC_BUF

Supply Voltage for Receiver Baseband Buffer. Bypass with capacitor as close to the pin as possible.

Do not share the bypass capacitor ground vias with other branches.

45

RX_ON

Receiver-On Control Input. Digital CMOS input. Connect to baseband IC mode control CMOS output.

46

VCC_RMX

Supply Voltage for Receiver Downconverter. Bypass with capacitor as close to the pin as possible.

Do not share the bypass capacitor ground vias with other branches.

47

TX_ON

Transmitter-On Control Input. Digital CMOS input. Connect directly to baseband IC mode control

CMOS output.

48

RX_AGC

Receive AGC Control. Analog high-impedance input. Connect directly to baseband IC DAC voltage

Exposed

Paddle

GND

DC and AC Ground Return for IC. Connect to PC board ground plane using multiple vias.