Signal
Name
Alternate
Function
Type Description
Battery Ground
BVSS
LVDD
GND
-
-
Connect this pin to the negative pin of the battery.
Low Voltage DC-DC Power Supply output
PWR
PWR
This pin outputs +1.8V typ. from internal DC-DC (battery powered).
Low Voltage Regulator Power Supply Output
This pin outputs +1.8V typ. from internal regulator (USB powered or
+3V external power supply).
Connect this pin to LVDD incase of internal DC-DC usage.
RLVDD
HVDD
-
-
High Voltage Power Supply
PWR
This pin outputs +3V typ. from internal regulator (USB powered).
Connect this pin to +3V external power supply.
Power Ground
VSS
GND
GND
PWR
GND
-
-
-
-
Connect this pin to the system ground.
Core Ground
CVSS
IOVDD
IOVSS
Connect this pin to VSS pin.
Input/Output Supply voltage
Connect this pin to LVDD or HVDD pin.
Input/Output Circuit Ground
Connect this pin to VSS pin.
OCD Interface
Table 16. OCD Signal Description
Signal
Name
Alternate
Function
Type Description
On Chip Debug Receive Input
OCDR
I
-
OCDR receives data.
On Chip Debug Transmit Output
OCDT
I/O
ISP
OCDT transmits data.
14
AT85C51SND3Bx
7632A–MP3–03/06
ATMEL [ ATMEL ]
