Sharp CD-C5H Service Manual page 65

ICT21 VHiLC72720/-1: RDS Microcomputer (LC72720)
Pin No. Terminal Name
1 VREF
2 MPXIN
3 VDDA
4 VSSA
5 FLOUT
6 CIN
7 T1
8 T2
9* T3 (RDCL)
10* T4 (RDDA)
11 * T5 (RSFT)
12 XOUT
13 XIN
14 VDDD
15 VSSD
16* T6 (ERROR/57K/BE1)
17* T7 (CORREC/ARI-ID/BE0
18* SYNC
19* RDS-ID
20 DO
21 CL
22 DI
23 CE
24 SYR
In this unit, the terminal with asterisk mark (*) is (open) terminal which is not connected to the outside.
ICT21 VHiLC72720/-1: RDS Microcomputer (LC72720)
VDDA
3
REFERENCE
VOLTAGE
VSSA 4
ANTIALIASING
MPXIN 2
FILTER
DO
20
CL
21
CCB
DI
22
CE
23
T1
7
T2
8
T3
9
T4 TEST
10
T5
11
T6
16
T7
17
Input/Output
Output Reference voltage output (Vdda/2)
Input Base band (multiplex) signal input
— Analog system power supply (+5V)
— Analog system ground
Output Sub-carrier input (comparator input)
Input Sub-carrier output (filter output)
Input Test input (to be always connected to ground)
Input Test input (standby control)
0: Normal operation/1: Standby state (crystal oscillation stop)
Input/Output Test I/O (RDS clock output)
Input/Output Test I/O (RDS data output)
Input/Output Test I/O (Soft judgment control data output)
Output Crystal oscillation output
Input Crystal oscillation input (external reference signal input)
— Digital system power supply
— Digital system ground
Input/Output Test I/O (Error existence/nonexistence output/playback carrier output/error block
number output)
Input/Output Test I/O (Error existence/nonexistence output/SK detection output/error block
number output)
Input/Output Block sync detection output
Output RDS detection output
Output Data output
Input Clock input
Input Data input
Input Chip enable
Input Sync and RAM address reset (positive logic)
FLOUT CIN
VREF
1 5
57kHz
BPF
SMOOTHING
(SCF)
FILTER
RAM
(24 BLOCK DATA)
MEMORY CONTROL
Figure 65 BLOCK DIAGRAM OF IC
Serial data interface (CCB)
6
PLL
(57kHz)
VREF
ERROR CORRECTION
(SOFT DECISION)
CLK(4.332MHz)
OSC/DIVIDER
13 12
XIN XOUT
– 65 –
CD-C5H,CP-C5H
Function
CLOCK
RECOVERY
(1187.5Hz)
DATA
DECODER
SYNC/EC CONTROLLER
SYNC SYNC
DETECT-1 DETECT-2
VDDD
14
VSSD
15
RDS-ID
19
SYNC
18
SYR
24