www.austriamicrosystems.com/AS8002

Revision 1.1

14 - 24

AS8002

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

7.7 Measurement Control and Calibration

The conversion starts on SCSB falling edge when adc_en is a 1. The value of the result of the conversion can be read at the next SPI write

command 10µs later.

Figure 9. ADC Burst Mode

Read_meas will be transferred to the Current, Voltage or Auxiliary measurement upon mux_sel[2:0] value – curr_meas, volt_meas or

aux_meas.

Calibration is done according to the formulas:

For current channel:

read_meas = adc_meas * (1024 + pga_curr_gain_cal) / 1024

(EQ 1)

For voltage channel:

read_meas = adc_meas * (1024 + pga_volt_gain_cal) / 1024

(EQ 2)

For auxiliary channel:

read_meas = adc_meas * (1024 + aux_gain_cal) / 1024

(EQ 3)

Note:

The Raw ADC results are also available in the registers and are called adc_meas[11:0]

7.8 Interrupts

When an over current, an under voltage or an over temperature occurs the bit warning_detected is set to 1.

The interrupt state is present on interrupt_detected and on the pin XINT.

The statuses are available in the register Interrupt Status. It contains the bits over_currrent_int_en, under_voltage_int_en,

over_temp_int_en.

The generation of the interrupt can be enabled or disabled in the register “Interrupt Enable”. It contains the bits over_currrent_int_i,

under_voltage_int_i, over_temp_int_i.

Values of the register Interrupt Status are kept until this register is read.

Table 7. Current and Voltage Measurements

Name

Content

b15

b14

b13

b12

b11:b0

Current Measurement

0

warning_detected

interrupt_detected

X

curr_meas

Voltage Measurement

0

warning_detected

interrupt_detected

X

volt_meas

channel_1

channel_2

channel_3

channel_1

channel_2

Not updated

Not updated

SCSB

channel measured

channel read