3803 Datasheet, PDF (24/119 Pages) Renesas Technology Corp – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER

3803 Group (Spec.L)
Termination of unused pins
• Termination of common pins
I/O ports: Select an input port or an output port and follow
each processing method.
In addition, it is recommended that related
registers be overwritten periodically to prevent
malfunctions, etc.
Output ports: Open.
Input ports: If the input level become unstable, through current
flow to an input circuit, and the power supply
current may increase.
Especially, when expecting low consumption
current (at STP or WIT instruction execution etc.),
pull-up or pull-down input ports to prevent
through current (builtin resistor can be used).
We recommend processing unused pins through a
resistor which can secure IOH(avg) or IOL(avg).
Because, when an I/O port or a pin which have an
output function is selected as an input port, it may
operate as an output port by incorrect operation
etc.
Table 7 Termination of unused pins
Pins
P0, P1, P2, P3, P4, P5, P6
VREF
AVSS
XOUT
Termination
• Set to the input mode and connect each to VCC or VSS through a resistor of 1 kΩ to 10 kΩ.
• Set to the output mode and open at “L” or “H” output state.
Connect to VCC or VSS (GND).
Connect to VCC or VSS (GND).
Open (only when using external clock)
Rev.1.00 Apr 2, 2007 Page 24 of 117
REJ03B0212-0100