Datasheet

MAX3311E/MAX3313E
±15kV ESD-Protected, 460kbps, 1µA,
RS-232-Compatible Transceivers in µMAX
6 _______________________________________________________________________________________
high data rates. 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.
±15kV ESD Protection
As with all Maxim devices, ESD-protection structures
are incorporated on all pins to protect against electro-
static discharges encountered during handling and
assembly. The MAX3311E/MAX3313E driver outputs
and receiver inputs have extra protection against static
discharge. Maxim’s engineers have developed state-of-
the-art structures to protect these pins against ESD of
±15kV without damage. The ESD structures withstand
high ESD in all states: normal operation, shutdown, and
powered down. After an ESD event, Maxim’s E versions
keep working without latchup; whereas, competing
products can latch and must be powered down to
remove latchup.
ESD protection can be tested in various ways. The
transmitter outputs and receiver inputs of the product
family are characterized for protection to ±15kV using
the Human Body Model.
ESD Test Conditions
ESD performance depends on a variety of conditions.
Contact Maxim for a reliability report that documents
test setup, test methodology, and test results.
Human Body Model
Figure 5 shows the Human Body Model, and Figure 6
shows the current waveform it generates when dis-
charged into low impedance. This model consists of a
100pF capacitor charged to the ESD voltage of interest,
which is then discharged into the test device through a
1.5kΩ resistor.
Machine Model
The Machine Model for ESD tests all pins using a
200pF storage capacitor and zero discharge resis-
tance. Its objective is to emulate the stress caused by
contact that occurs with handling and assembly during
manufacturing. Of course, all pins require this protec-
tion during manufacturing, not just RS-232 inputs and
outputs. Therefore, after PC board assembly, the
Machine Model is less relevant to I/O ports.
Figure 2. Loopback Test Circuit
C1
C2
0.1µF
V-
TOUT
TIN
ROUT
1000pF
RIN
V
CC
GND
5k
+5V
MAX3311E
MAX3313E
C1+
C1-
Figure 4. Loopback Test Results at 250kbps
2µs/div
TOUT
TIN
ROUT
Figure 3. Loopback Test Results at 120kbps
5µs/div
TOUT
TIN
ROUT