MAX239 Maxim Integrated Products, MAX239 Datasheet - Page 11

• Manufacturer Part Number: MAX239
• Description: (MAX220 - MAX249) +5V-Powered / Multichannel RS-232 Drivers/Receivers
• Manufacturer: Maxim Integrated Products

Figure 1. Transmitter Propagation-Delay Timing
Figure 3. Receiver-Output Enable and Disable Timing
INPUT
OUTPUT
b) ENABLE TIMING
c) DISABLE TIMING
a) TEST CIRCUIT
t
PLHT
+3V
RECEIVER
RECEIVER
OUTPUTS
OUTPUTS
EN INPUT
EN INPUT
R
X
V
V
EN
OH
OL
IN
______________________________________________________________________________________
+3V
0V
R
X
R
X
0V
OUT
150pF
+3V
0V
1kΩ
+5V-Powered, Multichannel RS-232
OUTPUT DISABLE TIME (t
OUTPUT ENABLE TIME (t
V
V
+3.5V
+0.8V
OH
OL
+ 0.5V
- 0.5V
EN
EN
V
V
CC
CC
- 2V
- 2V
t
PHLT
ER
DR
0V
V-
V+
)
)
Figure 2. Receiver Propagation-Delay Timing
Figure 4. Transmitter-Output Disable Timing
OUTPUT
*EXCEPT FOR R2 ON THE MAX243
INPUT
WHERE -3V IS USED.
t
t
PHLR
PHLS
SHDN
1 OR 0
b) TEST CIRCUIT
a) TIMING DIAGRAM
V+
V-
0V*
Drivers/Receivers
+3V
T
X
50%
50%
+3V
0V
3kΩ
OUTPUT DISABLE TIME (t
+5V
-5V
50pF
0V
50%
50%
GND
DT
t
t
PLHR
PLHS
)
V
CC
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