DA7838.002
20 September, 2000
$33/,&$7,21 ,1)250$7,21
+5v
RS232C
TXD
TTL/V28
78189A
470pF
Synchronous
Modem
TDO
TXC
RDI
RXC
TTL-Level
TTL-Level
TTL-Level
TTL-Level
*)
16 x TXC
RXC
TXC
TDI
9
16
10
4
+12v
TTL/V28
RDO
13
75189A
+5v
+5v
-12v
TSL
XHST
1
12
7
5
6
8
14
15
RXD
470pF
MAS7838
2
22pF
3x
4.75k
Ext. Signal Rate
Char. Length
Char. Length
CR 1
9.8304MHz
3
22pF
ASY/SYN Select 11
Modem
Timing
Circuit
mode
selection
jumpers
+5v
*) Optional timing from the
synchronous modem.
In this case CR 1 can be
eliminated.
MAS7838 simplified application:
V.28 interface for synchronous modem
7 (9)