FUNCTIONAL DIAGRAM OF DS232A Figure 1
DS232A
NOTE: C5 is a recommended decoupling capacitor which is the same value as C1, C2, C3, and C4.
( ) Are for TSSOP package only.
PIN DESCRIPTIONS
VCC, GND: DC power is provided to the device on these pins. VCC is the +5-volt input.
V+: Positive supply output (RS-232). V+ requires an external storage charge capacitor of at least 0.1 µF.
A larger capacitor (up to 10 µF) can be used to reduce supply ripple.
V-: Negative supply output (RS-232). V- requires an external storage capacitor of at least 0.1 µF. A
larger capacitor (up to 10 µF) can be used to reduce supply ripple.
T1IN, T2 IN: Standard TTL/CMOS inputs for the RS-232 drivers. The inputs of unused drivers can be left
unconnected since each input has a 400 kΩ pullup resistor.
T1OUT, T2 OUT: Driver outputs at RS-232 levels. Driver output swing meets RS-232 levels for loads up to
3 kΩ. These driver outputs provide current necessary to meet RS-232 levels for loads up to 2500 pF.
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