No. 6651-9/12
LC72346W, 72347W
Continued from preceding page.
Pin No.
Pin
I/O
Function
I/O circuit
System reset input.
In CPU operating mode or halt mode, applications must apply a low level for at least
one full machine cycle to reset the system and restart execution with the PC set to
location 0. This pin is connected in parallel with the internal power on reset circuit.
57
RES
I
Output for the 3 V step-up circuit clock. Outputs 1/2 the AM local oscillator frequency
in AM reception mode, and 1/256 the FM local oscillator or 75 kHz in FM reception
mode.
31
VDC1
O
Voltage stepped up by the DC-DC converter (3 V)
May also be used to input an equivalent voltage.
30
VDC3
I
RAM backup power supply. Connected to the VDC3 voltage through a diode.
29
VDDRAM
I
VDC3 voltage adjustment pin. Insert a 10 k
trimmer between this pin and ground to
adjust the VDC3 voltage.
32
VADJ
O
FM VCO (local oscillator) input.
This pin is selected with the PLL instruction CW1.
The input must be capacitor coupled.
Input is disabled in backup mode, in halt mode, after a reset, and in PLL stop mode.
59
FMIN
I
CMOS amplifier input
AM VCO (local oscillator) input.
This pin and the bandwidth are selected with the PLL instruction CW1.
The input must be capacitor coupled.
Input is disabled in backup mode, in halt mode, after a reset, and in PLL stop mode.
60
AMIN
I
CMOS amplifier input
Main charge pump output. When the local oscillator frequency divided by N is higher
than the reference frequency a high level is output, when lower, a low level is
output,and the pin is set to the high-impedance state when the frequencies match.
This output goes to the high-impedance state in backup mode, in halt mode, after a
reset, and in PLL stop mode.
62
EO
O
Power supply pin.
This pin must be connected to ground.
This pin must be connected to ground.
This pin must be connected to V
DD
. Supports A/D converter.
—
61
28
58
V
SS
V
SS
V
DD
—
CMOS push-pull
CW1 b1, b0
Input pins
Bandwidth
1
0
AMIN (H)
2 to 20 MHz (SW)
1
1
FMIN (L)
0.5 to 10 MHz (MW, LW)
Note
*
: When a pin in an I/O switching port is used as an output, applications must first set up the data with an OUT, SPB, or RPB instruction and then set up
output mode with an IOS instruction.