Philips PM2517E Service Manual page 55

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3.4-4.2.
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Specifications of inputs and outputs
Description
D i g i t S e l e c t
Digit Select
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1 0
I J
V s s ( - 8 , 5 V )
C L O C K
Latch Enable
(Not used in PlVl 251 7 E )
A u t o m a t i c R a n g i n g
Range Extention
R a n g e C
R a n g e B
Range A
l\4anual rangang
U p o r d o w n
Test input
Supply
Clock input
O n e o f t h e o u t p u t s ( D S 2 ) i s u s e d f o r t h e p h a s e c l o c k o f t h e L i q u i d
Cristal Display, for the clock'input of the OO 0055 and for the
phase inputs of the LX drivers HEF 4543.
P u l s e f o r I a t c h i n g t h e B C D i n f o r m a t i o n f o r a L X d i s p l a y .
The LAEN pulse is fed to a 1 of 4 decoder to disable the decoder
w h i l e D S 1 a n d D S 2 a r e c h a n g i n g .
Logic 1 is automatic ranging.
The range information wi!l be changed when the measuring result
is ( 900 and ) 9999.
< 9 0 0 = d o w n r a n g i n g
) 9999 = up ranging
Logic 0 no automatic ranging (manual ranging)
Range switching can be effected by the manual range switches.
With this signal the ranges can be extended.
This signal is used in the function Q and is activated by the
function switch.
Logic 0 = the range switch span consists of 4 ranges.
Logic 1 = the range span consists of 6 ranges.
Range information
n o a c t i o n
down rangrng
u p r a n g i n g
not specified
0
0
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0
1
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Test pin for lC testing during manufacturing.
The testpin is connected to Vss -8.5 V.
Negativ€ supply voltage (-8.5 V)
I n c o m i n g c l o c k f r e q u e n c y f r o m O O 0 0 6 0 ( 8 0 k H z . . . 1 2 0 k H z )
Digit Select Outputs
IVlSD lvl ost Signi{icant Digit
Manual range iniormation