Datasheet

Figure 6a shows the transmitter output voltages under
increasing load current at +3.0V. Figure 6b shows a typi-
cal mouse connection using the MAX3241E.
High Data Rates
The MAX3222E/MAX3232E/MAX3237E/MAX3241E/
MAX3246E maintain the RS-232 ±5V minimum trans-
mitter output voltage even at high data rates. Figure 7
shows a transmitter loopback test circuit. Figure 8 shows
a loopback test result at 120kbps, and Figure 9 shows
the same test at 250kbps. For Figure 8, all transmitters
were driven simultaneously at 120kbps into RS-232 loads
in parallel with 1000pF. For Figure 9, a single transmitter
was driven at 250kbps, and all transmitters were loaded
with an RS-232 receiver in parallel with 1000pF.
The MAX3237E maintains the RS-232 ±5.0V minimum
transmitter output voltage at data rates up to 1Mbps.
Figure 10 shows a loopback test result at 1Mbps with
MBAUD = V
CC
. For Figure 10, all transmitters were
loaded with an RS-232 receiver in parallel with 250pF.
Interconnection with 3V and 5V Logic
The MAX3222E/MAX3232E/MAX3237E/MAX3241E/
MAX3246E can directly interface with various 5V logic
families, including ACT and HCT CMOS. See Table 3
for more information on possible combinations of inter-
connections.
UCSP Reliability
The UCSP represents a unique packaging form factor that
may not perform equally to a packaged product through
traditional mechanical reliability tests. UCSP reliability is
integrally linked to the user’s assembly methods, circuit
board material, and usage environment. The user should
closely review these areas when considering use of a
UCSP package. Performance through Operating Life Test
and Moisture Resistance remains uncompromised as the
wafer-fabrication process primarily determines it.
Mechanical stress performance is a greater consideration
for a UCSP package. UCSPs are attached through direct
solder contact to the user’s PC board, foregoing the
inherent stress relief of a packaged product lead frame.
Solder joint contact integrity must be considered. Table
4 shows the testing done to characterize the UCSP reli-
ability performance. In conclusion, the UCSP is capable
of performing reliably through environmental stresses as
indicated by the results in the table. Additional usage data
and recommendations are detailed in Application Note
1891: Wafer-Level Packaging (WLP) and Its Applications.
Table 4. Reliability Test Data
TEST CONDITIONS DURATION
FAILURES PER
SAMPLE SIZE
Temperature Cycle
T
A
= -35°C to +85°C,
T
A
= -40°C to +100°C
150 cycles,
900 cycles
0/10,
0/200
Operating Life T
A
= +70°C 240 hours 0/10
Moisture Resistance T
A
= +20°C to +60°C, 90% RH 240 hours 0/10
Low-Temperature Storage T
A
= -20°C 240 hours 0/10
Low-Temperature Operational T
A
= -10°C 24 hours 0/10
Solderability 8-hour steam age — 0/15
ESD ±15kV, Human Body Model — 0/5
High-Temperature Operating Life T
J
= +150°C 168 hours 0/45
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Maxim Integrated │ 15
MAX3222E/MAX3232E/
MAX3237E/MAX3241E/
MAX3246E
±15kV ESD-Protected, Down to 10nA,
3.0V to 5.5V, Up to 1Mbps,
True RS-232 Transceivers