Datasheet
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SBAS404B –OCTOBER 2006– REVISED JANUARY 2012
Table 3. Control Register (CR)
ACTIVE IN
BIT NAME DESCRIPTION HARDWARE MODE
0 = Channel pair C disabled for next conversion (default)
C31 CH_C No
1 = Channel pair C enabled
0 = Channel pair B disabled for next conversion (default)
C30 CH_B No
1 = Channel pair B enabled
0 = Channel pair A disabled for next conversion (default)
C29 CH_A No
1 = Channel pair A enabled
0 = Input voltage range selection for channel pair C: 4V
REF
(default)
C28 RANGE_C No
1 = Input voltage range selection for channel pair C: 2V
REF
0 = Input voltage range selection for channel pair B: 4V
REF
(default)
C27 RANGE_B No
1 = Input voltage range selection for channel pair B: 2V
REF
0 = Input voltage range selection for channel pair A: 4V
REF
(default)
C26 RANGE_A No
1 = Input voltage range selection for channel pair A: 2V
REF
0 = Internal reference source disabled (default)
C25 REF
EN
No
1 = Internal reference source enabled
0 = Internal reference buffers enabled (default)
C24 REFBUF No
1 = Internal reference buffers disabled
0 = Sequential convert start mode disabled (default)
C23 SEQ No
1 = Sequential convert start mode enabled (bit 11 must be '1' in this case)
0 = Normal operation (default)
C22 A-NAP Yes
1 = Auto-NAP feature enabled
0 = BUSY/INT pin in normal mode (BUSY) (default)
C21 BUSY/INT Yes
1 = BUSY/INT pin in interrupt mode (INT)
0 = BUSY active high while INT active low (default)
C20 BUSY L/H Yes
1 = BUSY active low while INT active high
C19 Don’t use This bit is always set to '0' —
0 = Internal reference voltage: 2.5V (default)
C18 VREF Yes
1 = Internal reference voltage: 3V
0 = Normal operation (conversion results available on SDO_x) (default)
C17 READ_EN Yes
1 = Control register contents output on SDO_x with next access
0 = Control register bits C[31:24] update only (serial mode only) (default)
C16 C23:0_EN Yes
1 = Entire control register update enabled (serial mode only)
0 = Normal operation (default)
C15 PD_C Yes
1 = Power-down for channel pair C enabled (bit 31 must be '0' in this case)
0 = Normal operation (default)
C14 PD_B Yes
1 = Power-down for channel pair B enabled (bit 30 must be '0' in this case)
0 = Normal operation (default)
C13 PD_A Yes
1 = Power-down for channel pair A enabled (bit 29 must be '0' in this case)
C12 Don't use This bit is always '0' —
0 = Normal operation with internal conversion clock (mandatory in hardware mode) (default)
C11 CLKSEL No
1 = External conversion clock (applied through pin 27) used
0 = Normal operation (default)
C10 CLKOUT_EN No
1 = Internal conversion clock available at pin 27
C9 REFDAC[9] Bit 9 (MSB) of reference DAC value; default = 1 Yes
C8 REFDAC[8] Bit 8 of reference DAC value; default = 1 Yes
C7 REFDAC[7] Bit 7 of reference DAC value; default = 1 Yes
C6 REFDAC[6] Bit 6 of reference DAC value; default = 1 Yes
C5 REFDAC[5] Bit 5 of reference DAC value; default = 1 Yes
C4 REFDAC[4] Bit 4 of reference DAC value; default = 1 Yes
C3 REFDAC[3] Bit 3 of reference DAC value; default = 1 Yes
C2 REFDAC[2] Bit 2 of reference DAC value; default = 1 Yes
C1 REFDAC[1] Bit 1 of reference DAC value; default = 1 Yes
C0 REFDAC[0] Bit 0 (LSB) of reference DAC value; default = 1 Yes
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