MAX3245ECAI+ Maxim Integrated Products, MAX3245ECAI+ Datasheet - Page 9

• Manufacturer Part Number: MAX3245ECAI+
• Description: IC TXRX RS232 1MBPS SD 28-SSOP
• Manufacturer: Maxim Integrated Products
• Type: Transceiverr

Specifications of MAX3245ECAI+

• Number Of Drivers/receivers: 3/5
• Protocol: RS232
• Voltage - Supply: 3 V ~ 5.5 V
• Mounting Type: Surface Mount
• Package / Case: 28-SSOP
• Propagation Delay Time Ns: 0.15 us
• Operating Supply Voltage: 3 V to 5.5 V
• Supply Current: 0.3 mA
• Operating Temperature Range: 0 C to + 70 C
• Data Rate: 1 Mbps
• Mounting Style: SMD/SMT
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

Figure 1. Interface Under Control of PMU
The transmitters are inverting level translators that
convert CMOS-logic levels to 5.0V EIA/TIA-232 levels.
The MAX3224E/MAX3226E/MAX3244E guarantee a
250kbps data rate (1Mbps, for the MAX3225E/MAX3227E/
MAX3245E) with worst-case loads of 3kΩ in parallel with
1000pF, providing compatibility with PC-to-PC com-
munication software (such as LapLink™). Transmitters
can be paralleled to drive multiple receivers. Figure 1
shows a complete system connection.
When FORCEOFF is driven to ground or when the Auto-
Shutdown Plus circuitry senses that all receiver and
transmitter inputs are inactive for more than 30s, the
transmitters are disabled and the outputs go into a high-
impedance state. When powered off or shut down, the
outputs can be driven to ±12V. The transmitter inputs
do not have pullup resistors. Connect unused inputs to
GND or V
LapLink is a trademark of Traveling Software.
±15kV ESD-Protected, 1µA, 1Mbps 3.0V to 5.5V,
POWER-
MANAGEMENT
UNIT OR
KEYBOARD
CONTROLLER
CPU
RS-232 Transceivers with AutoShutdown Plus
CC
.
WITH
UART
CHIP
INVALID
FORCEOFF
FORCEON
I/O
_______________________________________________________________________________________
RS-232 Transmitters
MAX3244E
MAX3245E
RS-232
Figure 2. The MAX3244E/MAX3245E detect RS-232 activity
when the UART and interface are shut down.
b)
a)
OLDER RS-232: POWERED-DOWN UART DRAWS CURRENT FROM ACTIVE
RECEIVER OUTPUT IN SHUTDOWN.
EXTERNAL DEVICES AND R2OUT IS THREE STATED, ELIMINATING A CURRENT
PATH THROUGH THE UART'S PROTECTION DIODE.
V
NEW MAX3244E/MAX3245E: IN SHUTDOWN, R2OUTB IS USED TO MONITOR
V
CC
CC
UART
GND
GND
UART
TO
μP
PROTECTION
DIODE
PROTECTION
DIODE
Rx
Rx
Tx
Tx
TRANSITION
DETECTOR
LOGIC
SHDN = GND
FORCEOFF = GND
THREE-STATED
V
CC
I
V
R2OUTB
CC
R2OUT
T1IN
I
PREVIOUS
MAX3244E
MAX3245E
RS-232
5kΩ
5kΩ
R2IN
T1OUT
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