ADE7169F16 Datasheet, PDF (69/140 Pages) Analog Devices – Single-Phase Energy Measurement IC with 8052 MCU, RTC and LCD driver

Preliminary Technical Data
ADE7169F16
Temperature ADC interrupt
The temperature ADC can generate an ADC interrupt when at
least one of the following conditions occurs:
- The difference between the new temperature ADC value and
the last temperature ADC value generating an ADC interrupt is
larger than the value set in the TEMP_DIFF bits.
- The Temperature ADC conversion, initiated by setting Start
ADC Measurement SFR (ADCGO, 0xD8), is finished.
When the ADC interrupt occurs, a new value is available in the
Temperature ADC value SFR (TEMPADC, 0xD7). Note that
there is no flag associated with this interrupt.
BATTERY MEASUREMENT
To provide a digital battery measurement, the ADE7169F16
includes a dedicated ADC. The battery measurement is
available in an 8-bit SFR (Battery ADC value SFR (BATADC,
0xDF). The battery measurement has a resolution of 15
mV/LSB. A battery conversion can be initiated by two methods:
- Single Battery Measurement
- Background Battery Measurements
Single Battery Measurement
Set the BATT_ADC_GO bit in the Start ADC Measurement
SFR (ADCGO, 0xD8) to get a battery measurement. An
interrupt will be generated when the conversion is done and the
battery measurement is available in the Battery ADC value SFR
(BATADC, 0xDF).
Background Battery measurements
To configure background measurements for the battery,
establish a measurement interval in the Peripheral ADC Strobe
Period SFR (STRBPER, 0xF9). Then battery measurements will
be performed periodically in the background – see Table 45.
When a battery conversion completes, the battery ADC value is
compared to the low battery threshold, established in the
Battery detection threshold SFR (BATVTH, 0xFA). If it is below
this threshold, a low battery flag is set. This low battery flag is
the BATTFLAG bit in the Power Management Interrupt Flag
SFR (IPSMF, 0xF8), used for power supply monitoring. This low
battery flag can be enabled to generate the PSM interrupt by
setting the EBATT bit in the Power Management Interrupt
Enable SFR (IPSME, 0xEC). This method allows battery
measurements to take place completely in the background, only
requiring MCU activity if the battery drops below a user
specified threshold.
To set up background battery measurements:
1. Configure the Battery detection threshold SFR
(BATVTH, 0xFA) to establish a low battery threshold.
If the BATADC measurement is below this threshold,
the BATTFLAG in the Power Management Interrupt
Flag SFR (IPSMF, 0xF8) will be set.
2. Set up the interval for background battery
measurements by configuring the
BATT_PERIOD[1:0] bits.
Battery ADC in PSM1 and PSM2
Depending on the operating mode, a battery conversion is
initiated only by certain actions:
PSM0: In this operating mode, the 8052 is active. Battery
measurements are available in the background measurement
mode and by initiating a single measurement.
PSM1: In this operating mode, the 8052 is active and the part is
powered from battery. Single battery measurements can be
initiated by setting the BATT_ADC_GO bit in the Start ADC
Measurement SFR (ADCGO, 0xD8). Background battery
measurements are not available.
PSM2: In this operating mode, the 8052 is not active. Battery
conversions are available through the background measurement
mode only.
Battery ADC interrupt
The battery ADC can generate an ADC interrupt when at least
one of the following conditions occurs:
- The new battery ADC value is smaller than the value set in the
Battery detection threshold SFR (BATVTH, 0xFA), indicating a
battery voltage loss.
- A single battery measurement, initiated by setting the
BATT_ADC_GO bit, is finished.
When the battery flag is set in the Power Management Interrupt
Flag SFR (IPSMF, 0xF8), a new ADC value is available in the
Battery ADC value SFR (BATADC, 0xDF). This battery flag can
be enabled as a source of the PSM interrupt to generate a PSM
interrupt every time the battery drops below a set voltage
threshold or after a single conversion initiated by setting the
BATT_ADC_GO bit is ready.
The Battery ADC value SFR (BATADC, 0xDF) is updated with
a new value only when the Battery flag is set in the Power
Management Interrupt Flag SFR (IPSMF, 0xF8).
SUPPLY VOLTAGE MEASUREMENT
To provide a digital supply voltage measurement, the
ADE7169F16 includes a dedicated ADC. An 8-bit SFR (Table
49. VSW ADC value SFR (VSWADC, 0xEF)) holds the results
of the conversion. The resolution of the supply voltage
measurement is TBD V/LSB. There are two ways to initiate a
supply voltage conversion:
- Single Supply Voltage Measurement
Rev. PrD | Page 69 of 140