Datasheet
Modes of Operation
The modes of operation for the MAX2830 are shutdown,
standby, transmit, receive, transmitter calibration, and
receiver calibration. See Table 32 for a summary of the
modes of operation. The logic-input pins, SHDN (pin 12)
and RXTX (pin 48), control the various modes.
Shutdown Mode
The MAX2830 features a low-power shutdown mode
that disables all circuit blocks, except the serial-inter-
face and internal registers, allowing the registers to be
loaded and values maintained, as long as V
CC
is
applied. Set SHDN and RXTX logic-low to place the
device in shutdown mode. After a supply voltage ramp
up, supply current in shutdown mode could be high.
Program the default value to SPI register 0 to eliminate
high shutdown current.
Standby Mode
The standby mode is used to enable the frequency syn-
thesizer block while the rest of the device is powered
down. In this mode, the PLL, VCO, and LO generators
Table 30. Register 14 (A3:A0 = 1110)
BIT RECOMMENDED DESCRIPTION
D13:D11 000 Set to recommended value.
D10 0 Reference Clock Output Divider Ratio. Set 1 to divide by 2 or set 0 to divide by 1.
D9 1 Refer ence C l ock Outp ut E nab l e. S et 1 to enab l e the r efer ence cl ock outp ut or set 0 to d i sab l e.
D8:D7 10 Set to recommended value.
D6:D0 XXXXXXX Crystal-Oscillator Fine Tune. Tunes crystal oscillator over ±20ppm to within ±1ppm.
Table 31. Register 15 (A3:A0 = 1111)
BIT RECOMMENDED DESCRIPTION
D13:D12 00 Set to recommended value.
D11:D10 00
Receiver I/Q Output Common-Mode Voltage Adjustment. Set D11:D10 = 00: 1.1V,
01: 1.2V, 10: 1.3V, 11: 1.45V.
D9:D0 0101000101 Set to recommended value.
Table 32. Operating Mode Table
LOGIC PINS
REGISTER
SETTINGS
CIRCUIT BLOCK STATES
MODE
SHDN RXTX
D1:D0
(A3:A0 = 0110)
Rx PATH Tx PATH
PLL, VCO,
LO GEN,
AUTOTUNER
CALIBRATION
SECTIONS ON
Shutdown 0 0 00 Off Off Off None
Standby 0 1 00 Off Off On None
Rx 1 0 X0 On Off On None
Tx 1 1 0X Off On On None
Rx Calibration 1 0 X1
On
(except LNA)
Upconverters On
Cal tone, RF phase
shift, Tx filter
Tx Calibration 1 1 1X Off
On (except PA
driver and PA)
On
AM detector,
Rx I/Q buffers
X = Don’t care.
Note: See Table 1 for Rx/Tx and antenna diversity operating mode.
X = Don’t care.
30
Maxim Integrated
2.4GHz to 2.5GHz 802.11g/b RF Transceiver, PA,
and Rx/Tx/Antenna Diversity Switch
MAX2830