Data Sheet
October 2001
Dual Differential Transceivers
BTK1A and BTM1A
Electrical Characteristics
For variations in electrical characteristics over the temperature range, see Figure 10 on page 10 through Figure 12
Table 3. Power Supply Current Characteristics
T
A
=
−
40 °C to +125 °C, V
CC
= 5 V
±
0.5 V.
Parameter
Power Supply Current (V
CC
= 5.5 V):
All Outputs Disabled:
BTK1A
BTM1A
All Outputs Enabled:
BTK1A
BTM1A
Symbol
Min
Typ
Max
Unit
I
CC
I
CC
I
CC
I
CC
40
80
20
80
65
115
35
115
mA
mA
mA
mA
Third State
These drivers produce pseudo-ECL levels, and the third-state mode is different than the conventional TTL devices.
When a driver is placed in the third state, the bases of the output transistors are pulled low, bringing the outputs
below the active-high and active-low levels. This voltage is typically 2 V for most drivers. In the bidirectional bus
application, the driver of one device, which is in its third state, may be back driven by another driver on the bus
whose voltage in the low state is lower than the third-stated device. This could come about due to differences in the
drivers’ independent power supplies. In this case, the device in the third state will control the line, thus clamping
the line and reducing the signal swing. If the difference voltage between the independent power supplies and the
drivers is small, then this consideration can be ignored. In the typical case, the difference voltage can be as much
as 1 V without significantly affecting the amplitude of the driving signal.
Agere Systems Inc.
3
AGERE [ AGERE SYSTEMS ]
