MAX3316 Datasheet, PDF (11/15 Pages) Maxim Integrated Products – 2.5V, 1uA, 460kbps, RS-232-Compatible Transceivers

2.5V, 1µA, 460kbps,
RS-232-Compatible Transceivers
RECEIVER
INPUTS
} INVALID
REGION
TRANSMITTER
INPUTS
TRANSMITTER
OUTPUTS
INVALID
OUTPUT
V_CC
t_INVL
0
t_INVH
t_AUTOSHDN
t_AUTOSHDN
t_WU
t_WU
READY *V_CC
OUTPUT
0
V+
V_CC
0
V-
*MAX3318/MAX3319
Figure 4b. AutoShutdown Plus, INVALID, and READY Timing Diagram
POWER-
MANAGEMENT
UNIT
MASTER SHDN LINE
0.1µF 1MΩ
FORCEOFF FORCEON
MAX3318
MAX3319
Figure 5. AutoShutdown Plus Initial Turn-On to Wake Up a
Mouse or Another System
C2, C3, C4, and C_BYPASS to maintain proper ratios
(C1 to other capacitors).
When using the minimum-required capacitor values,
make sure the capacitor value does not degrade exces-
sively with temperature. If in doubt, use capacitors with
a higher nominal value. The capacitor’s equivalent
series resistance (ESR), which usually rises at low tem-
peratures, influences the amount of ripple on V+ and V-.
Power-Supply Decoupling
In most circumstances, a 0.1µF bypass capacitor is
adequate. In applications that are sensitive to power-
supply noise, decouple V_CC to ground with a capacitor
of the same value as charge pump capacitor C1.
Connect bypass capacitors as close to the IC as possible.
Transmitter Outputs when
Exiting Shutdown
Figure 2 shows two transmitter outputs when exiting
shutdown mode. As they become active, the two trans-
mitter outputs are shown going to opposite RS-232-
compatible levels (one transmitter input is high, the
other is low). Each transmitter is loaded with 3kΩ in par-
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