±15kV ESD-Protected, 1µA, 250kbps, 3.3V/5V, Dual
RS-232 Transceivers with Internal Capacitors
______________________________________________________________Pin Description
PIN
1
6
2
3
4
5
7
19
8
20
9
10
11, 12
13
14
15
16
17
18
NAME
R2OUT
R1OUT
INVALID
T2N
T1IN
FORCEON
T1OUT
T2OUT
R1IN
R2IN
VCC
FORCEOFF
V+
C1+
C1-
C2+
C2-
V-
GND
TTL/CMOS Receiver Outputs
FUNCTION
Invalid Signal Detector Output, active low. A logic high indicates that a valid RS-232
level is present on a receiver.
TTL/CMOS Transmitter Outputs
Force-On Input, active high. Drive high to override AutoShutdown Plus, keeping
transmitters and receivers active (FORCEOFF must be high) (Table 1).
RS-232 Transmitter Outputs
RS-232 Receiver Outputs
Supply Voltage (MAX3233E = +3.3V, MAX3235E = +5.0V)
Force-Off Input, active low. Drive low to shut down transmitters, receivers, and charge
pump. This overrides AutoShutdown Plus and FORCEON (Table 1).
+5.5V generated by the charge pump. Do not connect.
Positive terminal of the internal voltage-doubling charge-pump capacitor. Leave
unconnected or connect to an external 0.1µF capacitor. See Charge Pump Section.
Negative terminal of the internal voltage-doubling charge-pump capacitor. Leave
unconnected or connect to an external 0.1µF capacitor. See Charge Pump Section.
Positive terminal of the internal inverting charge-pump capacitor. Do not connect.
Negative terminal of the internal inverting charge-pump capacitor. Do not connect.
-5.5V generated by the charge pump. Do not connect.
Ground
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