3. RES: Reset pin

• Keep the length of lines (Lres in the figure) from the RES pin to external circuits as short as possible.

4. TEST: Test pin

5. AD0 to AD7: Analog input pins

Analog input pin lines, such as those used to connect to an A/D converter input pin or a comparator input pin should

be connected so as to meet the following conditions.

• Keep the line (L1) between the limiting resistor (Rl) and the analog input pin as short as possible.

• Locate the capacitor inserted between the analog input pins and the AV- pin (the A/D converter reference voltage

input pin) as close as possible to the AV- input pin. That is, make the line length L1 + L2 as short as possible.

6. I/O pins

All of the pins on these products function as both input and output pins.

• When used as an input pin, insert a limiting resistor, and keep the length of the line to that pin as short as possible.

Supplement: This is not only useful in printed circuit board design, but is also useful in preventing and avoiding

problems (such as incorrect microcontroller operation and program failures) by taking the program specifications

and microcontroller option selections described below into consideration.

• If signals are input from external sources when the microcontroller power supply is unstable, select the medium-

voltage handling capacity (n-channel open drain) output as the output type option for that input pin, and also insert

a limiting resistor in the input circuit.

• Always implement key chattering exclusion measures for external signals applied to microcontroller input pins.

• The pin output data should be re-output periodically with an output instruction (OP or SPB).

No. 6278-38/39

LC651154N, 651154F, 651154L, 651152N, 651152F, 651152L

Figure 3 RES Pin Wiring

Figure 4 TEST Pin Wiring

Figure 5 Analog Input Pin Wiring

External

circuit

External circuit

(sensor block)

Analog

input pin