Akai GX-M10

3. CIRCUIT CONSTRUCTION OF
IC2 MSM 5953RS
Function BCD UP/DOWN COUNTER/7
SEGMENT DECODER/DRIVER
Construction CMOS IC
1) Block Diagram
uP IN C1)
1
SCHMIDT
CONTROL
j
1
I
I
|
{
I
|
I
'
!
i
u/D ()
DOWN OUT
DOWN IN
r
2) Terminals and their functions
1.
2
3.
UP IN: Counts up (+1) using the raised portion
_FL of the pulse.
DOWN IN: Counts down (—1) using the falling
portion +J of the pulse. Does not count at 0.
DOWN OUT: Outputs when there is DOWN IN
input. ,
When a condenser is attached between this
and GND, after input enters the DOWN IN
terminal, the delayed time can be adjusted up —
until the counter counts down.
. U/D (UP/DOWN): There is input to the DOWN
IN terminal but counts down only when this
‘terminal is Low Level.
f
(3) COUNTER
I
\
I
(2) SCHMIDT
|
I
|
BCD 7
SEGMENT
DECODER
1a)
~
(6) BORROW OUT
SEGMENT
DRIVER OUT
ant eaerFr Aa
-----©®OG0O@---
Fig.9 MSM5953RS
. RBI (Ripple Blanking Input): When put to
Low Level the counter display (LED) is extin-
guished.
BORROW OUT: There is momentary output
when there is DOWN input after the counter
goes from 1 to Qor from 0.
. RESET: When put to Low Level the counter is
reset to 0.
to 15 SEGMENT OUT: Connects the Anode
Common 7 Segment LED.
Light up when put to Low Level.