Changhong Electric 21NF55, Service Manual, Page: 25 / 83

SERVICE MANUAL
23
SYMBOL PIN DESCRIPTION
B2/UIN 48 2nd B input/U (B-Y) input
BCLIN 49 beam current limiter input/(V-guard input, note2)
BLKIN 50 black current input/(V-guard input, note2)
RO 51 Red output
GO 52 Green output
BO 53 Blue output
VDDA
54
analog supply of Teletext decoder and digital supply of TV-processor
(3.3V)
VPE 55 OTP programming Voltage
VDDC 56 digital supply to core (3.3V)
OSCGND 57 oscillator ground supply
XTALIN 58 crystal oscillator input
XTALOUT 59 crystal oscillator output
RESET 60 reset
VDDP 61 digital supply to periphery (+3.3V)
P1.0/INT1 62 port 1.0 or external interrupt 1 input
P1.1/TO 63 port 1.1 or Counter/Timer 0 input
P1.2/INTO 64 port 1.2 or external interrupt 0 input
Notes
1)The function of pin 20, 28, 29, 31, 32, 35 and 44 is dependent on the IC version (mono intercarrier
FM demodulator/QSS IF amplifier and East-West output or not) and on some software control bits.
The valid combinations are given in table 5.
Table 6 Pin functions for various versions
IC version FM-PLL Version QSS Version
East-West
Y/N
N Y N Y
CMB1/CM
BO bits
00 01/10/11 00 01/10/11 00 01/10/11 00 01/10/11
AM bit - - - - - 0 1 - 0 1
Pin 20 AVL EWD AVL EWD
Pin 28 AUDEEM SIFIN1
Pin 29 DECSDEM SIFIN2
Pin 31 SNDPLL SIFAGC
Pin 32 SNDIR
(1)
REFO
(2)
AVL/SNDIF
(1)
REFO
(2)
AMOUT REFO
(2)
AMOUT REFO
(2)
Pin 35 AUDEXT AUDEXT QSSO AMOUT AUDEXT QSSO AMOUT
Pin44 AUDOUT Controlled AM or audio out
Notes
1)When additional(external) selectivity is required for FM-PLL system pin 32 can be used as sound IF
input. This function is selected by means of SIF bit in subaddress 28H.
2)The reference output signal is only available for the CMB1/CMBO setting of 0/1. For the other setings
this pin is a switch output.