10
8Bit Single Chip Microcontroller
DMC73C168
NAME
VCOH
Pin No.
75
I/O
I
FUNCTION DESCRIPTION
FM VCO input port.
PORT TYPE
Analog-IN
Only Pulse swallow method is used for this port.
The range of local oscillator output is 10MHz to 150MHz
with 0.3Vp-p minimum.
The output is required by capacitor coupling because an
AC amplifier is contained.
VCOL
76
I
AM VCO input port.
Analog-IN
This terminal can be selected by direct-dividing method
or pulse-swallow method.
In direct-dividing method, the range of local oscillator
output is 0.5MHz to 10MHz with 0.3Vp-p minimum, and
in pulse-swallow method, the range of local oscillator
output is 5MHz to 40MHz with 0.3Vp-p minimum.
Input to this port should be coupled by capacitor coupling
because and AC amplifier is contained.
VDD
28
77
Power source port.
The terminal supplies 5V ¡ 1¾0% for normal operation.
VREF
VDD and VREF must be connected to the same electric
potential. VDD is a power for logic circuit and VREF is a
power for analog circuit in the device.
NC
70
No connection
EO1
EO2
71
72
O
O
Phase comparison error output ports.
3-State-OUT
The divided frequency of VCO output and the reference
frequency are compared in their phase.
If divided frequency is higher than the reference frequency,
output signal is logic high level. If divided frequency is
lower than the reference frequency, output signal is vice
versa. When two frequencies are matched, port become a
floating state.
EO1 and EO2 have the same waveform.
TEST
29
I
Internal Chip Test port.
It should be connected to VSS.
VSS
73, 25
74
Ground reference
VASS
VSS is a ground for logic circuit and VASS is a ground for
Analog circuit in the device
OSCOUT
OSCIN
27
26
O
I
Crystal oscillator input and output ports.
Connect 4.5MHz Crystal.
DAEWOO ELECTRONICS CO., LTD.
DAEWOO [ DAEWOO Electronic Components ]
