Datasheet

Detailed Description
The MAX2830 single-chip, low-power, direct conversion,
zero-IF transceiver is designed to support 802.11g/b
applications operating in the 2.4GHz to 2.5GHz band.
The fully integrated transceivers include a receive path,
transmit path, VCO, sigma-delta fractional-N synthesizer,
crystal oscillator, RSSI, PA power detector, temperature
sensor, Rx and Tx I/Q error-detection circuitry, baseband-
control interface, linear power amplifier, and an Rx/Tx
antenna diversity switch. The only additional components
required to implement a complete radio front-end solution
are a crystal, a pair of baluns, a BPF, and a small number
of passive components (RCs, no inductors required).
Rx/Tx and Antenna Diversity Switches
The MAX2830 integrates an Rx/Tx switch and an anten-
na diversity switch before the receiver and after the
power amplifier. See Figure 1 for a block diagram of the
switches. The receiver and transmitter enable pin
(RXTX) and the antenna selection pin (ANTSEL) deter-
mine which ports (ANT1 or ANT2) the receiver or trans-
mitter is connected to. See Table 1 for the Rx/Tx and
antenna diversity switches truth table. When RXTX = 0
(receive mode) and ANTSEL = 0, the switch provides a
low-insertion loss path (main) between the ANT1 port
(pins 4 and 5) and the receiver. When RXTX = 0
(receive mode) and ANTSEL = 1, the switch provides
Pin Description (continued)
PIN NAME FUNCTION
35 RXBBQ-
36 RXBBQ+
Receiver Baseband Q-Channel Differential Outputs. In TX calibration mode, these pins are the LO leakage
and sideband detector outputs.
37 RXBBI-
38 RXBBI+
Receiver Baseband I-Channel Differential Outputs. In TX calibration mode, these pins are the LO leakage
and sideband detector outputs.
39 V
CCRXVGA
Receiver VGA Supply Voltage
40 RXHP Receiver Baseband AC-Coupling High-Pass Corner Frequency Control Logic Input
41 V
CCRXFL
Receiver Baseband Filter Supply Voltage
42 TXBBQ-
43 TXBBQ+
Transmitter Baseband I-Channel Differential Inputs
44 TXBBI-
45 TXBBI+
Transmitter Baseband Q-Channel Differential Inputs
46 V
CCRXMX
Receiver Downconverters Supply Voltage
47 ANTSEL Antenna Selection Logic Input. See Table 1 for operation
48 RXTX Rx/Tx Mode Control Logic Input. See Table 32 for operating modes.
—EP
Exposed Paddle. Connect to the ground plane with multiple vias for proper operation and heat dissipation.
Do not share with any other pin grounds and bypass capacitors' ground.
Table 1. Rx/Tx and Antenna Diversity Switches Operation
RXTX ANTSEL MODE ANTENNA
0 0 Rx (main) Ant1_
0 1 Rx (diversity) Ant2_
1 X Tx Ant2_
MAX2830
2
2
ANT1
2
2
LNA
PA
2
ANT2
Figure 1. Simplified Rx/Tx and Antenna Diversity Switch Structure
20
Maxim Integrated
2.4GHz to 2.5GHz 802.11g/b RF Transceiver, PA,
and Rx/Tx/Antenna Diversity Switch
MAX2830