MAX3221
3 V TO 5.5 V SINGLE CHANNEL RS 232 LINE DRIVER/RECEIVER
WITH
±15
kV ESD PROTECTION
SLLS348M − JUNE 1999 − REVISED MARCH 2004
PARAMETER MEASUREMENT INFORMATION
2.7 V
Receiver
Input
ROUT
Generator
(see Note B)
50
Ω
tinvalid
50% VCC
tvalid
VCC
INVALID
Output
V+
Supply
Voltages
V−
TEST CIRCUIT
VOLTAGE WAVEFORMS
50% VCC
0V
ten
≈V+
0.3 V
VCC
0V
0.3 V
≈V−
−2.7 V
−2.7 V
2.7 V
3V
0V
0V
−3 V
Auto-
powerdown
INVALID
CL = 30 pF
(see Note A)
FORCEOFF
FORCEON
DIN
DOUT
Valid RS-232 Level, INVALID High
2.7 V
0.3 V
0V
−0.3 V
−2.7 V
† Auto-powerdown disables drivers and reduces supply
current to 1
µA.
NOTES: A. CL includes probe and jig capacitance.
B. The pulse generator has the following characteristics: PRR = 5 kbit/s, ZO = 50
Ω,
50% duty cycle, tr
≤
10 ns, tf
≤
10 ns.
Figure 5. INVALID Propagation Delay Times and Driver Enabling Time
POST OFFICE BOX 655303
•
DALLAS, TEXAS 75265
ÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎ
ÎÎÎÎÎÎÎÎÎÎÎÎ
Indeterminate
If Signal Remains Within This Region
For More Than 30
µs,
INVALID Is Low†
Indeterminate
Valid RS-232 Level, INVALID High
9
TI [ TEXAS INSTRUMENTS ]
