Datasheet

AMC7812

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SBAS513E –JANUARY 2011–REVISED SEPTEMBER 2013

ADC CHANNEL REGISTER 0 (Read/Write, Address = 50h, Default = 0000h)

MSB LSB

BIT 15 BIT 14 BIT 13 BIT 12 BIT 11 BIT 10 BIT 9 BIT 8 BIT 7 BIT 6 BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0

DF DF

0 SE0 SE1 (CH0+/ SE2 SE3 (CH2+/ SE4 SE5 SE6 SE7 SE8 SE9 SE10 SE11 SE12

CH1–) CH3–)

These bits specify the external analog auxiliary input channels (CH0 to CH12) to be converted. The specified

channel(s) is accessed sequentially in order from bit 14 to bit 0. The input is converted when the corresponding

bit is set ('1').

Bit 15 Reserved. Writing to this bit causes no change. Reading this bit returns '0'.

Bits 14, 13, 11, 10, 8:0 SE0 to SE12. External single-ended analog input for CHn. The result is stored in ADC-n-Data Register in

straight binary format.

Bit 12 DF (CH0+CH1 –). External analog differential input pair, CH0 and CH1, with CH0 as positive and CH1 as

negative. The difference of (CH0 – CH1) is converted and the result is stored in the ADC-0-Data Register in twos

complement format.

DF(CH2+/CH3-). External analog differential input pair, CH2 and CH3, with CH2 as positive and CH3 as

Bit 9 negative. The difference of (CH2 – CH3) is converted and the result is stored in the ADC-2-Data Register in twos

complement format.

Table 23. CH0 and CH1 Bit Settings

BIT 14 BIT 13 BIT 12 DESCRIPTION

1 1 0 CH0 and CH1 are both accessed as single-ended inputs. Bit 12 is ignored.

1 0 0 CH0 is accessed as a single-ended input. CH1 is not accessed. Bit 12 is ignored.

0 1 0 CH1 is accessed as a singled-ended. CH0 is not accessed. Bit 12 is ignored.

0 0 1 Differential input pair CH0 + and CH1– is accessed as a differential input.

0 0 0 CH0, CH1, and differential pair CH0+/CH1– are not accessed.

Table 24. CH2 and CH3 Bit Settings

BIT 11 BIT 10 BIT 9 DESCRIPTION

1 1 0 CH2 and CH3 are both accessed as single-ended inputs. Bit 9 is ignored.

1 0 0 CH2 is accessed as a single-ended input. CH3 is not accessed. Bit 9 is ignored.

0 1 0 CH3 is accessed as a singled-end input. CH2 is not accessed. Bit 9 is ignored.

0 0 1 Differential input pair CH2+ and CH3– is accessed as a differential input.

0 0 0 CH2, CH3, and differential pair CH2+/CH3– are not accessed.

Table 25. CH4 to CH12 Bit Settings

BIT 8 BIT 7 BIT 6 BIT 5 BIT 4 BIT 3 BIT 2 BIT 1 BIT 0 DESCRIPTION

1 — — — — — — — — CH4 is accessed as a single-ended input

— 1 — — — — — — — CH5 is accessed as a single-ended input

— — 1 — — — — — — CH6 is accessed as a single-ended input

— — — 1 — — — — — CH7 is accessed as a single-ended input

— — — — 1 — — — — CH8 is accessed as a single-ended input

— — — — — 1 — — — CH9 is accessed as a single-ended input

— — — — — — 1 — — CH10 is accessed as a single-ended input

— — — — — — — 1 — CH11 is accessed as a single-ended input

— — — — — — — — 1 CH12 is accessed as a single-ended input

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