REV. G

–14–

ADM3307E/ADM3310E/ADM3311E/ADM3312E/ADM3315E

ESD TESTING (IEC 1000-4-2)

IEC 1000-4-2 (previously 801-2) specifies compliance testing using

two coupling methods, contact discharge and air-gap discharge.

Contact discharge calls for a direct connection to the unit being

tested. Air-gap discharge uses a higher test voltage but does not

make direct contact with the unit under testing. With air discharge,

the discharge gun is moved toward the unit under testing, which

develops an arc across the air gap, thus the term air discharge.

This method is influenced by humidity, temperature, barometric

pressure, distance, and rate of closure of the discharge gun. The

contact discharge method, while less realistic, is more repeatable

and is gaining acceptance in preference to the air-gap method.

Although very little energy is contained within an ESD pulse,

the extremely fast rise time coupled with high voltages can cause

failures in unprotected semiconductors. Catastrophic destruction

can occur immediately as a result of arcing or heating. Even if

catastrophic failure does not occur immediately, the device may

suffer from parametric degradation that may result in degraded

performance. The cumulative effects of continuous exposure can

eventually lead to complete failure.

I/O lines are particularly vulnerable to ESD damage. Simply

touching or plugging in an I/O cable can result in a static discharge

that can damage or completely destroy the interface product

connected to the I/O port. Traditional ESD test methods, such as

the MIL-STD-883B method 3015.7, do not fully test a product’s

susceptibility to this type of discharge. This test was intended to

test a product’s susceptibility to ESD damage during handling. Each

pin is tested with respect to all other pins. There are some impor-

tant differences between the traditional test and the IEC test:

(a) The IEC test is much more stringent in terms of discharge

energy. The peak current injected is over four times greater.

(b) The current rise time is significantly faster in the IEC test.

(c) The IEC test is carried out while power is applied to the device.

It is possible that the ESD discharge could induce latch-up in the

device under test. This test, therefore, is more representative of

a real world I/O discharge where the equipment is operating

normally with power applied. For maximum peace of mind,

however, both tests should be performed, ensuring maximum

protection both during handling and later during field service.

R1

R2

C1

DEVICE

UNDER TEST

HIGH

VOLTAGE

GENERATOR

ESD TEST METHOD

R2

C1

HUMAN BODY MODEL

ESD ASSOC. STD 55.1

1.5kV

100pF

IEC1000-4-2

330V

150pF

Figure 9. ESD Test Standards

100

90

36.8

10

TIME t

Figure 10. Human Body Model ESD Current Waveform

100

90

10

TIME t

30ns

60ns

0.1 TO 1ns

Figure 11. IEC1000-4-2 ESD Current Waveform

The ADM33xxE devices are tested using both of the previously

mentioned test methods. All pins are tested with respect to all

other pins as per the Human Body Model, ESD Assoc. Std. 55.1

specification. In addition, all I/O pins are tested as per the

IEC 1000-4-2 test specification. The products were tested under

the following conditions:

(a) Power-On—Normal Operation

(b) Power-Off

There are four levels of compliance defined by IEC 1000-4-2. The

ADM33xxE parts meet the most stringent compliance level for

both contact and air-gap discharge. This means the products are

able to withstand contact discharges in excess of 8 kV and air-

gap discharges in excess of 15 kV.

Table V. IEC 1000-4-2 Compliance Levels

Level

Contact Discharge (kV)

Air Discharge (kV)

12

2

24

4

36

8

48

15