MAX3180E Datasheet, PDF (5/8 Pages) Maxim Integrated Products – +-15kV ESD-Protected, 0.5UA, +3V to +5.5V, 1.5Mbps RS-232 Receivers in SOT23-5

±15kV ESD-Protected, 0.5µA, +3V to +5.5V,
1.5Mbps RS-232 Receivers in SOT23-5
+2.7V
+0.3V
0
-0.3V
-2.7V
VALID SIGNALS
INDETERMINATE
INVALID SIGNALS
INDETERMINATE
VALID SIGNALS
RECEIVER
INPUT
VOLTAGE
(V)
V_CC
INVALID
OUTPUT
(V)
0
t_INVL
INVALID
REGION
t_INVH
Figure 2. Input Levels and INVALID Timing
Signal Invalid Detector
If no valid signal levels appear on RIN for 30µs (typ),
INVALID goes low. This event typically occurs if the
RS-232 cable is disconnected, or if the connected
peripheral transmitter is turned off. INVALID goes high
when a valid level is applied to the RS-232 receiver
input. Figure 2 shows the input levels and timing dia-
gram for INVALID operation.
Enable Input
The MAX3180E/MAX3182E feature an enable input
(EN). Drive EN high to force ROUT into a high-imped-
ance state. In this state, the devices ignore incoming
RS-232 signals. Pull EN low for normal operation.
ESD Protection
As with all Maxim devices, ESD protection structures
are incorporated on all pins to protect against ESD
encountered during handling and assembly. The
receiver inputs of the MAX3180E–MAX3183E have extra
protection against static electricity. Maxim’s engineers
have developed state-of-the-art structures enabling
these pins to withstand ESD up to ±15kV without dam-
age or latchup. The receiver inputs of the MAX3180E–
MAX3183E are characterized for protection to the fol-
lowing limits:
• ±15kV using the Human Body Model
• ±8kV using the Contact Discharge method specified
in IEC 1000-4-2
• ±15kV using the Air-Gap Discharge method speci-
fied in IEC 1000-4-2
Human Body Model
Figure 3 shows the Human Body Model, and Figure 4
shows the current waveform it generates when dis-
charged into a low impedance. This model consists of
R_C
1MΩ
CHARGE-CURRENT
LIMIT RESISTOR
HIGH-
VOLTAGE
DC
SOURCE
Cs
100pF
R_D
1500Ω
DISCHARGE
RESISTANCE
STORAGE
CAPACITOR
DEVICE
UNDER
TEST
Figure 3. Human Body ESD Test Model
I_P 100%
90%
AMPERES
36.8%
10%
0
0 _tRI
Ir
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
TIME
t_DL
CURRENT WAVEFORM
Figure 4. Human Body Model Current Waveform
a 100pF capacitor charged to the ESD voltage of inter-
est, and then discharged into the test device through a
1.5kΩ resistor.
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