MAX3212
+2.7V to +3.6V-Powered, 1µA Supply Current,
3-Driver/5-Receiver, True RS-232 Transceiver
10 ______________________________________________________________________________________
_____+3V-Powered EIA/TIA-232 and EIA/TIA-562 Transceivers from Maxim
-7
-5
0
TRANSMITTER OUTPUT VOLTAGE
vs. LOAD CURRENT PER TRANSMITTER
MAX3212-06
LOAD CURRENT PER TRANSMITTER (mA)
TRANSMITTER OUTPUT VOLTAGE (V)
-3
-1
3
1
5
7
12345
V
CC
= 3.3V
V
CC
= 2.7V
T1IN AND T2IN = GND
T3IN = V
CC
T3OUT, T2OUT, T1OUT
ALL LOADED
SIMULTANEOUSLY
6789
T3OUT
T1OUT AND T2OUT
Figure 6. Mouse Emulation Circuit Current
0.1µF capacitors, AutoShutdown,
complementary receiver,
drives mice
23212013/53.0 to 5.5MAX3243
0.1µF capacitors232120N/A2/23.0 to 5.5MAX3232
0.1µF capacitors, AutoShutdown23212022/23.0 to 5.5MAX3223
0.1µF capacitors23212022/23.0 to 5.5MAX3222
232
562
232
562
232
EIA/TIA-
232
OR 562
2.7 to 3.6
AutoShutdown, complementary
receiver, drives mice, transient
detection
23553/5MAX3212
0.1µF capacitors23022/23.0 to 3.6MAX563
Operates directly from batteries
without a voltage regulator
12022/21.8 to 4.25MAX218
No. OF
RECEIVERS
ACTIVE IN
SHUTDOWN
POWER-
SUPPLY
VOLTAGE
(V)
Wide supply range23053/52.7 to 5.25MAX562
Drives mice12053/53.0 to 3.6MAX212
FEATURES
GUAR-
ANTEED
DATA
RATE
(kbps)
No. OF
TRANSMITTERS/
RECEIVERS
PART
Driving the MAX3212 from 5V Logic
The MAX3212 can directly interface with various 5V
logic families, including ACT and HCT CMOS.
Mouse Driveability
The MAX3212 has been specifically designed to power
serial mice while operating from low-voltage power sup-
plies. It has been tested with samples of ten major
mouse models from six manufacturers, including the
leading three, Logitech (5 models), Mouse Systems,
and Microsoft. The MAX3212 successfully drove all ser-
ial mice and met their respective current and voltage
requirements.
Figure 6 shows the transmitter output voltages under
increasing load current. The MAX3212’s switching reg-
ulator ensures the transmitters will supply at least ±5V
during worst-case load conditions.
0.1µF capacitors, 2 complemen-
tary receivers, drives mice
23212053/53.0 to 5.5MAX3241