HFC-SUSB Cologne Chip AG, HFC-SUSB Datasheet - Page 63

• Manufacturer Part Number: HFC-SUSB
• Description: Isdn S/t HDLC Basic Rate Controller
• Manufacturer: Cologne Chip AG

863 C EC2
7
7.1
In order to comply to the physical requirements of ITU-T recommendation I.430 and considering the
national requirements concerning overvoltage protection and electromagnetic compatibility (EMC), the
HFC-S USB needs some additional circuitry, which are shown in the following figures.
7.1.1 External receiver circuitry
Figure 7: External receiver circuitry
WAKE_UP_1 and WAKE_UP_2 are for connection of the wake up circuitry (see: 7.1.2 External wake-
up circuitry).
C1 and C2 are for reduction of high frequency input noise and should be placed as close as possible to
the HFC-S USB.
Part list
Part
C1
C2
C4
D1
D2
RA1
RA2
RB1
RB2
RC1
:e\i " !
A D J _L E V
L E V _ R 1
L E V _ R 2
R 1
R 2
External circuitries
S/T interface circuitry
Value
22p
22p
47n
BAV99
BAV99
100k
100k
33k
33k
4k7
C 1
C 2
G N D
R 1
R A 1
R A 2
R C 1
R C 2
R B 1
R B 2
R 3
V D D
D 2
D 1
R D 1
R D 2
Part
RC2
RD1
RD2
R1
R2
R3
ISDN_ST1 ISDN Connector
TR1
G N D
W A K E _ U P _1
W A K E _ U P _2
G N D
C 4
Value
4k7
4k7
4k7
3k9
1M
1M8
S/T transformer module
(see Table 5 on page 67)
R 2
TR 1 A
R E C
V D D
Cologne
Chip
I S D N _ S T1
&# _V ("
R E C 1
R E C 2
TR A N S 1
TR A N S 2