Datasheet

LTC4308
12
4308f
APPLICATIONS INFORMATION
Systems with Supply Voltage Droop
In large 2-wire systems, the V
CC
voltages seen by devices
at various points in the system can differ by a few hundred
millivolts or more
. This situation is modeled by a series
resistor in the V
CC
line, as shown in Figure 6. For proper
operation, make sure that the V
CC(LTC4308)
is ≥ 2.3V.
Table 1: Differences Between LTC4301l and LTC4308
SPECIFICATION LTC4301L LTC4308 COMMENTS
V
CC(MIN)
2.7V 2.3V Lower supply voltage allows greater compatibility with low voltage systems.
V
OS(TYP)
100mV –200mV/300mV Negative output-to-input offset voltage provide better noise margin on low voltage bus.
I
PULLUPAC(TYP)
N/A 8mA Output bus rise time accelerators aid heavily loaded busses to meet rise time specifi cations.
t
TIMEOUT
N/A 30ms Stuck Bus Recovery automatically isolates the input bus from the output bus and attempts to recover
the output bus.
READY – – READY functions identically. In addition, the LTC4308 will pull READY low to indicate when
disconnection has occurred.
CS/ENABLE Active Low Active High When replacing an LTC4301L with an LTC4308, invert the CS signal.
LTC4308 and LTC4301L Feature Comparison
Although both, the LTC4308 and LTC4301L are func-
tionally similar Hot Swappable Bus Buffers designed for
Low Voltage Level Translation in 2-wire bus systems, the
LTC4308 provides greater features. These features include
automatic bus stuck low detection and recovery; rise time
accelerators on the output busses, and –200mV In-Out and
300mV Out-In offset voltages that are nearly independent
of pull-up resistors. These and other differences are listed
in Table 1 and must be accounted for if using the LTC4308
in LTC4301L applications.