HFC-4S Cologne Chip AG, HFC-4S Datasheet - Page 156

• Manufacturer Part Number: HFC-4S
• Description: Isdn HDLC Fifo Controller With 8 (4) Integrated S/t Interfaces
• Manufacturer: Cologne Chip AG

HFC-4S
HFC-8S
156 of 273
U1
HFC-4S/HFC-8S
R1
T_Ax
T_Bx
+ 3 . 3 V
G N D
R3
R5
U1
HFC-4S/HFC-8S
T_Ax
T_Bx
C1
6 8 0 p
G N D
B C 8 5 8 C
C2
4 7 p
Q 3
Figure 5.7: External S/T transmit circuitry for TE and NT mode
Figure 5.8: External S/T transmit circuitry for NT mode only
Q 4
B C 8 4 8 C
R2
B C 8 4 8 C
Q 5
R 1 , R 2 :
V a l u e d e p e n d s o n t h e
u s e d S / T t r a n s f o r m e r
a n d t h e d e s i r e d
S / T a m p l i t u d e .
R4
R8
G N D
R 7 , R 9 :
V a l u e d e p e n d s o n t h e
u s e d S / T t r a n s f o r m e r
a n d i s u s e d t o a d j u s t
t h e t r a n s m i t t e r o u t p u t
i m p e d a n c e a n d t h e
d e s i r e d S / T a m p l i t u d e .
B C 8 4 8 C
B C 8 4 8 C
R1
R2
S/T interface
6 8
6 8
Q 1
Data Sheet
Q 2
G N D
4 7 p
C3
R7
R9
2 2
2 2
G N D
D1
D3
D2
B A V 9 9
B A V 9 9
G N D
5 V 6
R6
D1
D3
D2
B A V 9 9
B A V 9 9
n c
5 V 6
TR1B
TRANS
March 2003 (rev. A)
n c
TR1B
TRANS
Cologne
Chip