ES51993
11,000 Counts ADC
4.4 Buzzer Setup
When the bit BUZ of ID Byte is set to “H”, the BUZOUT will output a square signal of
MPU I/O swing level to drive a external buzzer. The buzzer frequency is determined by
the bits B0/B1/B2 of STATUS Byte3. The configuration of buzzer frequency is listed at
the following table.
B2/B1/B0
BUZout (kHz)
111
110
101
100
011
010
001
000
4.00
3.33
3.08
2.67
2.22
2.00
1.33
1.00
4.5 Low Battery Detection
In a case of 3V battery power, the pin LBAT must be shorted to AGND. And the system
will have low battery detection level about 2.3V. In another case of 9V or other battery
power, the low battery detection happens when the voltage of LBAT is less than –1.23V
below GND. And the bit LBAT of STATUS Byte3 will be set to high. A recommended
application is shown as following:
Low battery test (9V)
BA
TT
V-
The low battery detection level is around 7V
4.6 Sleep Mode
When the pin CS is connected to V- or GND (depended on I/O_control level), the
ES51993 will enter sleep mode. In Sleep mode, the chip draws a little supply current. It
could extend the battery life. To leave sleep mode or stay in normal mode, the pin CS
must be connected to AGND or floating.
10
06/09/20
CYRUSTEK [ Cyrustek corporation ]
