Datasheet
MAX19706
10-Bit, 22Msps, Ultra-Low-Power
Analog Front-End
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In ENABLE-16 mode, the aux-DACs have independent
control bits E4, E5, and E6, and bit E9 enables the aux-
ADC. Table 7 shows the auxiliary DAC enable codes
and Table 8 shows the auxiliary ADC enable codes. Bits
E11 and E10 are reserved. Program bits E11 and E10 to
logic-low.
Modes aux-DAC1, aux-DAC2, and aux-DAC3 select
the aux-DAC channels named DAC1, DAC2, and
DAC3 and hold the data inputs for each DAC. Bits
_D11–_D0 are the data inputs for each aux-DAC and
can be programmed through SPI. The MAX19706 also
includes two 6-bit registers that can be programmed to
adjust the offsets for the Tx DAC I and Q channels
independently (see Table 9). Use the COMSEL mode
to select the output common-mode voltage with bits
CM1 and CM0 (see Table 10). Use aux-ADC mode to
start the auxiliary ADC conversion (see the 10-Bit,
333ksps Auxiliary ADC section for details). Use
ENABLE-8 mode for faster enable and switching
between shutdown, idle, and standby states as well as
switching between FAST, SLOW, and Rx and Tx
modes.
Table 6. Tx-Rx Control Using SPI Commands
ADDRESS DATA BITS T/R
A3 A2 A1 A0 E3 E2 E1 E0 PIN 27
MODE
FUNCTION
(Tx-Rx SWITCHING
SPEED)
DESCRIPTION COMMENTS
1011 X SPI1-Rx SLOW
Rx Mode:
Rx ADC = ON
Tx DAC = OFF
Rx Bus = Enable
Low Power:
Slow Rx to Tx through
SPI command.
1100 X SPI2-Tx SLOW
Tx Mode:
Rx ADC = OFF
Tx DAC = ON
Tx Bus = Enable
Low Power:
Slow Tx to Rx through
SPI command.
1101 X SPI3-Rx FAST
Rx Mode:
Rx ADC = ON
Tx DAC = ON
Rx Bus = Enabled
Moderate Power:
Fast Rx to Tx through
SPI command.
0000
(16-Bit Mode)
or
1000
(8-Bit Mode)
1110 X SPI4-Tx FAST
Tx Mode:
Rx ADC = ON
Tx DAC = ON
Tx Bus = Enabled
Moderate Power:
Fast Tx to Rx through
SPI command.
Table 7. Aux-DAC Enable Table
(ENABLE-16 Mode)
E6 E5 E4 AUX-DAC3 AUX-DAC2 AUX-DAC1
000ONONON
0 0 1 ON ON OFF
0 1 0 ON OFF ON
0 1 1 ON OFF OFF
1 0 0 OFF ON ON
1 0 1 OFF ON OFF
1 1 0 OFF OFF ON
1 1 1 OFF OFF OFF
Table 8. Aux-ADC Enable Table
(ENABLE-16 Mode)
E9 SELECTION
0 (Default) Aux-ADC is Powered ON
1 Aux-ADC is Powered OFF
X = Don’t care.