ES51991
11,000 Counts ADC
Pin Description
Pin No
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
Symbol
V-
AGND
V12
CAZ
CINT
CREF+
CREF-
REF+
REF-
BUF
RAZ
VIN+
VIN-
NC
SDATA
SCLK
EOC
BUZout
uP_VCC
OSC2
OSC1
C-
C+
CS
I/O_control
LBAT
Type
P
G
O
I
O
I/O
I/O
I
I
O
O
Description
27
28
DGND
V+
Negative supply voltage. Connecting to 3V battery negative terminal.
Analog ground
Output of band-gap voltage reference. Typically –1.23V
Auto-zero capacitor connection.
Integrator output. Connect to integral capacitor
Positive connection for reference capacitor.
Negative connection for reference capacitor.
Differential reference high voltage input.
Differential reference low voltage input.
Buffer output pin. Connect to integral resistor
Buffer output pin in high-speed mode. Connect to high-speed integral
resistor.
I
Analog differential high signal input.
I
Analog differential low signal input.
-
Not connected
I/O Serial data I/O pin. Nch open-drain output.
I
Serial clock input pin.
O An indicator for ADC conversion ending.
O Buzzer frequency output
I
MPU I/O port power level selection
O Crystal oscillation connection
I
Crystal oscillation connection
O Negative capacitor connection for on-chip DC-DC converter.
O Positive capacitor connection for on-chip DC-DC converter.
I
Chip select input pin. Pull to Low to enter power down mode.
I
MPU I/O port ground level selection
I
Low battery configuration. If 3V battery is used, connect it to AGND.
The default low-battery threshold voltage is –2.3V. If 9V or other
battery voltage is used, the low battery annunciator is displayed when
the voltage of this pin is less than V12
G Digital ground
O/P Output of on-chip DC-DC converter.
3
06/09/20
CYRUSTEK [ Cyrustek corporation ]
