UR5HC418 Datasheet, PDF (9/14 Pages) Semtech Corporation – AT / PS/2 - Compatible Keyboard Encoder

ALTERNATE SCHEMATIC FOR THE UR5HC418 WITH RESET CIRCUIT
Vcc
Telecom TC54VC4502ECB
2
1
Vcc
STATUS LEDs
EKDAT
EKBCLK
KBCLK
KBDAT
4 X 47pF
3
Vcc
GND
Vcc
1
44
5 12 38
RST
Vcc
NL CL SL
4.7K 4.7K 2K 2K
11
10
41
Vcc
2
9
8
23
GND
LINE INTERFACE
EKD
EKC
EKC1
IRQ
KC
KD
NC
8042
EMULATION
PORT
44 Pin PLCC
PC KEYBOARD
PORT
COMMUNICATIONS
C15
C14
C13
C12
C11
C10
C9
C8
COLUMN C7
SELECT C6
OUTPUTS C5
C4
C3
C2
C1
C0
C4A
R7A
R7
R6
ROW
R5
DATA
R4
INPUTS _R3
R2
R1
R0
OSCI
OSCO
Vss RP VXA
VX
43
42
22
73
4
1 MEG
4.00 MHz
GND
Vcc Vcc
Vcc
24
25
26
27
28
29
30
31
21
20
19
17
16
15
14
13
18
40
39
6
37
36
35
34
33
32
Vcc
8 x 22K
CS15
CS14
CS13
CS12
CS11
CS10
CS9
CS8
CS7
CS6
CS5
CS4
CS3
CS2
CS1
CS0
TO SWITCH MATRIX
RDAT7
RDAT6
RDAT5
RDAT4
RDAT3
RDAT2
RDAT1
RDAT0
GND
Copyright ©1997-2001 Semtech Corporation
9
DOC5-418-DS-109
www.semtech.com