±15kV ESD-Protected, 1µA, 16Mbps, Dual/Quad

Low-Voltage Level Translators in UCSP

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±15kV ESD Protection

As with all Maxim devices, ESD-protection structures are

incorporated on all pins to protect against electrostatic

discharges encountered during handling and assembly.

electricity. 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, three-state out-

put mode, 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 I/O

protection to the following limits:

1) ±15kV using the Human Body Model

2) ±8kV using the Contact Discharge method specified

in IEC 1000-4-2

3) ±10kV using IEC 1000-4-2’s Air-Gap Discharge

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 3a shows the Human Body Model and Figure 3b

shows the current waveform it generates when dis-

charged into a low impedance. This model consists of

a 100pF capacitor charged to the ESD voltage of inter-

est, which is then discharged into the test device

through a 1.5k

Ω resistor.

IEC 1000-4-2

The IEC 1000-4-2 standard covers ESD testing and

performance of finished equipment; it does not specifi-

cally refer to integrated circuits. The MAX3372E–

MAX3379E and MAX3390E–MAX3393E help to design

equipment that meets Level 3 of IEC 1000-4-2, without

the need for additional ESD-protection components.

The major difference between tests done using the

Human Body Model and IEC 1000-4-2 is higher peak cur-

rent in IEC 1000-4-2, because series resistance is lower

in the IEC 1000-4-2 model. Hence, the ESD withstand

voltage measured to IEC 1000-4-2 is generally lower than

that measured using the Human Body Model. Figure 4a

shows the IEC 1000-4-2 model, and Figure 4b shows the

current waveform for the ±8kV, IEC 1000-4-2, Level 4,

ESD contact-discharge test.

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.

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 inputs and outputs.

Therefore, after PC board assembly, the Machine

Model is less relevant to I/O ports.

CHARGE-CURRENT-

LIMIT RESISTOR

DISCHARGE

RESISTANCE

STORAGE

CAPACITOR

Cs

100pF

Ω

Ω

HIGH-

VOLTAGE

DC

SOURCE

DEVICE

UNDER

TEST

Figure 3a. Human Body ESD Test Model

90%

36.8%

TIME

CURRENT WAVEFORM

PEAK-TO-PEAK RINGING

(NOT DRAWN TO SCALE)

Ir

10%

0

0

AMPERES

Figure 3b. Human Body Current Waveform