ML2712 Datasheet, PDF (12/22 Pages) Micro Linear Corporation – 2.4GHz RF Transceiver

PRELIMINARY
ML2712
CONTROL INTERFACES
OPERATING MODE CONTROL
A parallel control interface dynamically controls the
four different Modes of operation. The control lines
TS (Pin 47), RS (Pin 48) and LOE (Pin 46) enable the
PLLs, VCOs, transmitter and receiver circuits. The
relationship between this control interface, the
Modes of operation and the functioning of the
circuits are described in Table 1. The function of this
control interface can be duplicated via the Serial
Control Bus, and the circuits enabled in STANDBY,
RECEIVE and TRANSMIT can be programmed via the
Serial Control Bus.
RS
TS
LOE
Mode
IC Status
High
High
Low
High
High
High
High
Low
High
Low
Low
Low
SLEEP
All radio circuits are off. Static CMOS control circuits are active, consuming
minimal current but permitting the register settings to be changed via the baseband
controller IC. Registers store power-up default or previously programmed values on
serial control lines. The baseband IC may configure the radio, while the radio is
neither transmitting nor receiving data, but the ML2712 will maintain the last
programmed values. Note that in SLEEP Mode the operating Mode control may be
overridden by the Serial Control Bus if parallel control interface is not required.
STANDBY
Only the VCO and PLL circuits are enabled in this mode and will be locked within
150msec. This will be flagged by an LD (lock detect) signal. The frequency divide
ratio settings will cause the two PLLs to lock to the desired frequencies. In this
mode the 2nd LO output signal can have a calibration signal added to the 2LO
VCO signal. This calibration signal is used for discriminator alignment on the
ML2713. The 8 bit DAC and associated comparator circuit are enabled.
RECEIVE
The Receive RF down-converter, 1LO PLL & VCO, 2LO PLL & VCO, RSSI DAC,
and RSSI comparator are all enabled, although for maximum flexibility any of these
circuits could be disabled via the Serial Control Bus.
TRANSMIT
The Transmit RF down-converter, Wideband PLL, 1LO PLL & VCO, 2LO PLL &
VCO, and RSSI D/A are all enabled, although for maximum flexibility any of these
circuits could be disabled via the Serial Control Bus
Table 1. Operating Mode ControlStates
12
PRELIMINARY DATASHEET ^{January, 2000}