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AS8002

Data Sheet - D e t a i l e d D e s c r i p t i o n

7.6 Measurement Example

The following example shows a simple way to alternately read the voltage and current values:

Bits [b2:b0] in Addr 03h control the ADC input multiplexer:

1. Select the Current channel input (IOM, IOP) : 0610h

- Set the Address [A6:A0] to 03h,

- Set the R/W bit to 0 (write mode) and the data to 10h (adc_en = 1, mux_sel = 0)

- In parallel to writing the 16-bit data on SDI, a set of 16-bit data can be read on SDO, which contains the data from the second to last

command.

2. Select the Voltage channel input (V1M, V1P) : 0611h

- Set the Address [A6:A0] to 03h,

- Set the R/W bit to 0 (write mode) and the data to 11h (adc_en = 1, mux_sel = 1)

- In parallel to writing the 16-bit data on SDI, a set of 16-bit data can be read on SDO, which contains the data from the second to last

command.

3. Change the input multiplexer back to Current channel input (IOM, IOP) : 0610h

- Repeat the sequence 1 above: addr = 03h, data = 10h,

- The 16-bit current input data from the second to last invoked command (1 above) can be read on SDO.

4. Loop sequences 2 and 3

Note:

In sequence 2, the 16-bit voltage input data from the second to last command can be read on SDO.

Figure 8. Measurement Diagram

Note:

The 16-bit input data from the voltage and current measurements contain the ADC data in the lower 12 bits and two status bits in the

upper 4 bits (see Register Map Table on page 15).

Name

Addr

Default

Content

b7

b6

b5

b4

b3

b2

b1

b0

Input Multiplexer

03h

00h

adc_en

mux_sel[2:0]

0: Current channel PGA output

1: Voltage channel PGA output

set Mux to

Current

measurement

set Mux to

Voltage

measurement

set Mux to

Current

measurement

set Mux to

Voltage

measurement

SDI

MSB

0610h

LSB

data from

previous

command

data from

previous

command

read Current

input value

read Voltage

input value

SDO

MSB

LSB

MSB

LSB

MSB

LSB

MSB

LSB

Transmission 1

Transmission 2

Transmission 3

Transmission 4

1)

2)

3)

4)=2)

MSB

0611h

LSB

MSB

0610h

LSB

MSB

0611h

LSB