Short-circuit protection, Chip information – Rainbow Electronics MAX3420E User Manual

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capacitors connected to ground as close to the pins as
possible. D+, D-, and VBCOMP provide protection to
the following limits:
• ±15kV using the Human Body Model
• ±8kV using the Contact Discharge method specified

in IEC 61000-4-2

• ±12kV using the IEC 61000-4-2 Air Gap Method

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 18 shows the Human Body Model, and Figure 19
shows the current waveform generated when dis-
charged into a low impedance. This model consists of
a 100pF capacitor charged to the ESD voltage of inter-
est, which then discharges into the test device through
a 1.5k

Ω resistor.

IEC 61000-4-2

The IEC 61000-4-2 standard covers ESD testing and
performance of finished equipment. It does not specifi-
cally refer to integrated circuits. The major difference
between tests done using the Human Body Model and
IEC 61000-4-2 is a higher peak current in IEC 61000-4-
2, due to lower series resistance. Hence, the ESD with-
stand voltage measured to IEC 61000-4-2 generally is
lower than that measured using the Human Body
Model. Figure 20 shows the IEC 61000-4-2 model. The
Contact Discharge method connects the probe to the
device before the probe is charged. The Air-Gap
Discharge test involves approaching the device with a
charged probe.

Short-Circuit Protection

The MAX3420E withstands V

BUS

shorts to D+ and D-

on the USB connector side of the 33

Ω series resistors.

Chip Information

PROCESS: BiCMOS

MAX3420E

USB Peripheral Controller

with SPI Interface

______________________________________________________________________________________

Figure 19. Human Body Model Current Waveform

100%

90%

36.8%

TIME

CURRENT WAVEFORM

PEAK-TO-PEAK RINGING
(NOT DRAWN TO SCALE)

10%

AMPERES

Figure 18. Human Body ESD Test Models

CHARGE-CURRENT-

LIMIT RESISTOR

DISCHARGE

RESISTANCE

STORAGE
CAPACITOR

100pF

Ω

1.5k

Ω

HIGH-

VOLTAGE

SOURCE

DEVICE

UNDER

TEST

Figure 20. IEC 61000-4-2 ESD Test Model