HDMP-1636 Datasheet, PDF (10/15 Pages) Agilent(Hewlett-Packard) – Gigabit Ethernet Transceiver Chip

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-1636/46 (TRx)
Pin Input Capacitance
Symbol
C_INPUT
Parameter
Input Capacitance on TTL Input Pins
O_TTL
V_CC_TTL
Units
pF
I_TTL
V_CC_TTL
R
R
V_CC_TX
or
V_CC_RX
R
R
Typ.
1.6
Max.
R
GND_TTL
ESD
PROTECTION
GND
ESD
PROTECTION
GND_TTL
V_BB 1.4 V
Figure 9. O-TTL and I-TTL Simplified Circuit Schematic.
HS_OUT
ESD
PROTECTION
V_CC_TXHS
V_CC_TXECL
V_CC_RXHS
V_CC_TX
V_CC_RX
+DOUT
150
R_PAD
Zo = 75 Ω
0.01
150
+DIN
-DOUT
GND
150
R_PAD
Zo = 75 Ω
0.01
-DIN
GND
GND_TXHS
GND_RXHS
HS_IN
+
–+
–
R
R
ESD
PROTECTION
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 25-75 Ω.
720