VESTEL 17MB18, Service Manual

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4.14. 74LVC541
The 74LVC541A is an octal non-inverting buffer/line driver with 5 V tolerant inputs/outputs. The 3-state outputs are
controlled by the output enable inputs OE1and OE2.
 5 V tolerant inputs/outputs; for interfacing with 5 V logic
 Wide supply voltage range from 2.7 to 3.6 V
 CMOS low-power consumption

Direct interface with TTL levels
INPUT OUTPUT
OE1 OE2 An Yn
L L L L
L L H H
X H X Z
H X X Z
Pin no Symbol Name and function
1
OE1
Output Enable Input
2, 3, 4, 5, 6, 7,
8, 9
A0 to A7 Data Inputs
11, 12, 13, 14,
15, 16, 17, 18
Y0 to Y7 Data Outputs
2A1 to 2A4 Data Inputs
1Y1 to 1Y4 Data Outputs
19
OE2
Output Enable Input
10 GND Ground (0V)
20 VCC Positive Supply Voltage
4.15. SAA3010T
The SAA3010 is intended as a general purpose (RC-5) infrared remote control system for use where a low voltage supply
and a large debounce time are expected. The device can generate 2048 different commands and utilizes a keyboard with
a single pole switch for each key. The commands are arranged so that 32 systems can be addressed, each system
containing 64 different commands. The circuit response to legal (one key pressed at a time) and illegal (more than one
key pressed at a time) keyboard operation is specified in the section “Keyboard operation”.
 Low voltage requirement
 Biphase transmission technique
 Single pin oscillator
 Test mode facility
Pin Mnemonic Function
1 X7 (IPU) sense input from key matrix
2 SSM (I) sense mode selection input
3 Z0-Z3 (IPU) sense inputs from key matrix
7 MDATA (OP3) generated output data modulated with 1/12 the oscillator frequency at a 25%
duty factor
8 DATA (OP3) generated output information
9-13 DR7-DR3
(ODN)
Scan drivers
14 VSS Ground (0V)
15-17 DR-2-DR0
(ODN)
Scan drivers
18 OSC (I) Oscillator input
19 TP2 (I) test point 2
20 TP1 (I) Test point 1
21-27 X0-X6 (IPU) Sense inputs from key matrix
28 VDD(I) Voltage supply
Note: