MAX1483CSA Maxim Integrated Products, MAX1483CSA Datasheet - Page 9

• Manufacturer Part Number: MAX1483CSA
• Description: RS-485 Interface IC
• Manufacturer: Maxim Integrated Products

Specifications of MAX1483CSA

• Lead Free Status / Rohs Status: No

A low-power shutdown mode is initiated by bringing RE
high and DE low. The devices will not shut down unless
both the driver and receiver are disabled. In shut-
down, the devices typically draw only 0.1µA of supply
current.
RE and DE may be driven simultaneously; the parts are
guaranteed not to enter shutdown if RE is high and DE
is low for less than 50ns. If the inputs are in this state for
at least 600ns, the parts are guaranteed to enter shut-
down.
For the receiver, the t
the part was not in the low-power shutdown state. The
t
parts were shut down (see Electrical Characteristics).
It takes the receivers longer to become enabled from
the low-power shutdown state (t
than from the operating mode (t
in operating mode if the RE , DE inputs equal a logical
0,1 or 1,1 or 0,0.)
Figure 11. Receiver t
ZH(SHDN)
500mV/div
5V/div
RO
A
B
and t
ZL(SHDN)
_______________________________________________________________________________________
PHL
Low-Power Shutdown Mode
ZH
20µA,
and t
500ns/div
enable times assume the
ZL
ZH
ZH(SHDN)
enable times assume
, t
ZL
1
). (The parts are
⁄
8
, t
-Unit-Load, Slew-Rate-Limited
ZL(SHDN)
)
Excessive output current and power dissipation caused
by faults or by bus contention are prevented by two
mechanisms. A foldback current limit on the output
stage provides immediate protection against short cir-
cuits over the whole common-mode voltage range (see
Typical Operating Characteristics). In addition, a ther-
mal shutdown circuit forces the driver outputs into a
high-impedance state if the die temperature rises
excessively.
Digital encoding schemes depend on the driver and
receiver skew. Skew is defined as the difference
between the rising and falling propagation delay times.
Typical propagation delays are shown in Figures 11
and 12 using Figure 10’s test circuit.
The difference in receiver delay times, | t
typically under 160ns.
The driver skew times are typically 160ns (800ns max).
Figure 12. Receiver t
500mV/div
5V/div
RS-485 Transceivers
RO
B
A
PLH
Driver Output Protection
500ns/div
Propagation Delay
PLH
- t
PHL
|, is
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