HDMP-1636A Datasheet, PDF (12/18 Pages) Agilent(Hewlett-Packard) – Gigabit Ethernet and Fibre Channel SerDes ICs

12
I/O Type Definitions
I/O Type
I-TTL
O-TTL
HS_OUT
HS_IN
C
S
Definition
Input TTL, Floats High When Left Open
Output TTL
High Speed Output, ECL Compatible
High Speed Input
External Circuit Node
Power Supply or Ground
HDMP-1636A/46A/T1636A (TRx)
Pin Input Capacitance
Symbol
C_INPUT
Parameter
Input Capacitance on TTL Input Pins
O_TTL
V_CC_RXTTL
Units
pF
I_TTL
V_CC
R
R
V_CC
R
R
Typ.
1.6
Max.
R
GND_RXTTL
ESD
PROTECTION
GND
ESD
PROTECTION
GND
V_BB 1.4 V
Figure 9. O-TTL and I-TTL Simplified Circuit Schematic.
HS_OUT
V_CC_TXHS
V_CC_TXECL
V_CC
HS_IN
V_CC
V_CC
+
–+
–
R
R
+DOUT
0.01 µF _+DIN
Zo
R_PAD
150
2 Zo
ESD
PROTECTION
-DOUT
R_PAD
GND
150
Zo
0.01 µF -DIN
GND
ESD
PROTECTION
GND_TXHS
GND
Figure 10. HS_OUT and HS_IN Simplified Circuit Schematic.
Notes:
1. HS_IN inputs should never be connected to ground as permanent damage to the device may result.
2. The optional series padding resistors (RPAD) help dampen load reflections. Typical RPAD values for mismatched loads range
between 25-Zo Ω.