MAX3314CKA-T Maxim Integrated, MAX3314CKA-T Datasheet - Page 4

• Manufacturer Part Number: MAX3314CKA-T
• Description: RS-232 Interface IC
• Manufacturer: Maxim Integrated
• Series: MAX3314r

Specifications of MAX3314CKA-T

• Data Rate: 460 Kbps
• Operating Supply Voltage: 4.75 V to 5.25 V
• Supply Current: 30 uA
• Operating Temperature Range: 0 C to + 70 C
• Number Of I/os: 1 / 1
• Propagation Delay Time Ns: 0.15 us

460kbps, 1µA, RS-232-Compatible Transceiver
The transmitter is an inverting level translator that con-
verts CMOS-logic levels to EIA/TIA-232-compatible lev-
els. It guarantees data rates up to 460kbps with
worst-case loads of 3kΩ in parallel with 1000pF. When
SHDN is driven low, the transmitter is disabled and put
into 3-state mode. The transmitter input does not have a
pull-up resistor. Connect to ground if unused.
The MAX3314’s receiver converts RS-232 signals to
CMOS-logic output levels. The receiver is rated to sig-
nals up to ±25V. The MAX3314’s receiver will remain
active during shutdown mode.
In shutdown mode, the transmitter output is put into
high impedance. This reduces the supply current to
1µA. The time required to exit shutdown is less than
2.5µs. Table 1 is the shutdown logic truth table.
The capacitor type used is not critical for proper opera-
tion; either polarized or nonpolarized capacitors are
acceptable. If polarized capacitors are used, connect
polarity as shown in the Typical Operating Circuit.
Bypass V
Figure 1 shows the transmitter output when exiting shut-
down mode. The transmitter is loaded with 3kΩ in par-
allel with 1000pF. The transmitter output displays no
ringing or undesirable transients as the MAX3314
comes out of shutdown. Note that the transmitter is
enabled only when the magnitude of V- exceeds
approximately -3V.
The MAX3314 maintains minimum RS-232-compatible
±3.7V transmitter output voltage even at high data rates.
4
Table 1. Shutdown Logic Truth Table
_______________________________________________________________________________________
SHDN
H
L
CC
and V- to ground with at least 0.1µF.
Applications Information
TRANSMITTER
RS-232-Compatible Receivers
OUTPUT
RS-232-Compatible Drivers
High-Z
Active
MAX3314 Shutdown Mode
Detailed Description
Transmitter Output When
Capacitor Selection
Exiting Shutdown
High Data Rates
RECEIVER
OUTPUT
Active
Active
Figure 2 shows a transmitter loopback test circuit.
Figure 3 shows the loopback test result at 120kbps, and
Figure 4 shows the same test at 250kbps.
TRANSISTOR COUNT: 128
Figure 1. Transmitter Output When Exiting Shutdown or
Powering Up
Figure 2. Loopback Test Circuit
CAPACITORS MAY BE POLARIZED OR NONPOLARIZED.
+5V
1.5V/div
5V/div
0.1µF
0
0
TIN
ROUT
MAX3314
1µs/div
GND
V
CC
Chip Information
SHDN
TOUT
5kΩ
TIN = GND
TIN = V
RIN
V-
CC
1000pF
0.1µF
TOUT
SHDN
-5V