MAX3110 MAXIM [Maxim Integrated Products], MAX3110 Datasheet - Page 23

• Manufacturer Part Number: MAX3110
• Manufacturer: MAXIM [Maxim Integrated Products]

Figure 8a. Human Body ESD Test Model
Figure 9a. IEC 1000-4-2 ESD Test Model
The air-gap test involves approaching the device with a
charged probe. The contact-discharge method connects
the probe to the device before the probe is energized.
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.
Protected RS-232 Transceivers with Internal Capacitors
VOLTAGE
SOURCE
HIGH-
VOLTAGE
SOURCE
DC
HIGH-
DC
CHARGE-CURRENT
SPI/MICROWIRE-Compatible UART and ±15kV ESD-
CHARGE-CURRENT
LIMIT RESISTOR
LIMIT RESISTOR
50M to 100M
R
R
1M
C
150pF
100pF
C
C s
______________________________________________________________________________________
C s
STORAGE
CAPACITOR
STORAGE
CAPACITOR
RESISTANCE
RESISTANCE
DISCHARGE
DISCHARGE
1500
330
R
R
D
D
Machine Model
DEVICE
UNDER
TEST
DEVICE
UNDER
TEST
The MAX3110E/MAX3111E include an oscillator circuit
derived from an external crystal oscillator for baud-rate
generation. For standard baud rates, use a 1.8432MHz
or 3.6864MHz crystal. The 1.8432MHz crystal results
in lower operating current; however, the 3.6864MHz
crystal may be more readily available in surface
mount.
Figure 8b. Human Body Model Current Waveform
Figure 9b. IEC 1000-4-2 ESD Generator Current Waveform
AMPERES
t r = 0.7ns to 1ns
I
P
36.8%
100%
90%
10%
100%
90%
10%
0
I
0
Applications Information
t
RL
30ns
Crystals, Oscillators, and
CURRENT WAVEFORM
TIME
60ns
t
Ceramic Resonators
DL
I r
PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)
t
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