SN8P2977
8-Bit Micro-Controller with Regulator, PGIA, 24-bit ADC
SONiX TECHNOLOGY CO., LTD
Page 66
Version 1.7
7.5 High-sink current I/O PORT
The SN8P2977 has a built-in High sink I/O to support drive seven-segment display from port P2/P3 and it with typical
60mA current sinking capacity. when the pin is LOW, it can only accept that much current flowing to ground.
When P2/P3 is high-current sink I/O mode, Advisable AI3/R+ pin to AVDDR, AI4/R- pin to ground and ADC reference
voltage set as External reference, avoid high current sink grounding influence ADC operation.
32768Hz
20p
ON/ OFF
Key 1
Key 2
20p
Optional for RTC Clock
Weight Scale Application Circuit
LQFP48-Pin, LED 4*8
10uf
1uf
LED
BLE
Module
VBAT
SN8P 2977
SEG1/P36
SEG0/P37
COM3
COM2
COM1
COM0
VLCD/VPP
AVDDR
AVE
AVSS
AVDD
NC
A
I1
A
I2
A
I3
/R
+
A
I4
/R
-
N
C
N
C
N
C
N
C
P
1
0/
LB
T0
P
1
1/
P
W
M
0
P
0
0/
IN
T
0
P
0
1/
IN
T1
P21/SEG14
P20/SEG15
NC
NC
DVDD
DVSS
LXOUT / P07
LXIN / P06
RX / P05
TX / P04
P03
P02
P
35
/S
EG
2
P
34
/S
EG
3
P
3
3/
SE
G
4
P
3
2/
SE
G
5
P
3
1/
SE
G
6
P
3
0/
SE
G
7
P
2
7/
SE
G
8
P
26
/S
E
G
9
P
2
5/
SE
G
1
0
P
2
4/
SE
G
1
1
P
2
3/
SE
G
1
2
P
2
2/
SE
G
1
3
1uf
VBAT
0.1uf
Load Cell
AVDDR
VBAT
VBAT
0.1uf
A
V
D
D
R
Note:
In High-current sink I/O mode, Recommend ADC reference voltage set external reference
IRVS[3:0]=11xx and AI3/R+ pin to AVDDR, AI4/R- pin to AVSS.