OPAX189 datasheet(24/52 Pages) TI

24 / 52 page

8.3.6 Electrical Overstress

Designers often ask questions about the capability of an operational amplifier to withstand electrical overstress.

These questions tend to focus on the device inputs, but may involve the supply voltage pins or even the output

pin. Each of these different pin functions have electrical stress limits determined by the voltage breakdown

characteristics of the particular semiconductor fabrication process and specific circuits connected to the pin.

Additionally, internal electrostatic discharge (ESD) protection is built into these circuits to protect from accidental

ESD events both before and during product assembly.

Having a good understanding of this basic ESD circuitry and the relevance to an electrical overstress event is

helpful. See Figure 8-4 for an illustration of the ESD circuits contained in the OPAx189 (indicated by the dashed

line area). The ESD protection circuitry involves several current-steering diodes connected from the input and

output pins and routed back to the internal power-supply lines, where the diodes meet at an absorption device

internal to the operational amplifier. This protection circuitry is intended to remain inactive during normal circuit

operation.

Op Amp

Core

(1)

OUT

+IN

ESD Current-

Steering Diodes

V+

(3)

TVS

(2)

Edge-Triggered ESD

Absorption Circuit

V±

TVS

(2)

(1) VIN = V+ + 500 mV.

(2) TVS: 40 V > VTVSBR (min) > V+ ; where VTVSBR (min) is the minimum specified value for the transient voltage suppressor breakdown

voltage.

(3) Suggested value is approximately 5 kΩ in overvoltage conditions.

Figure 8-4. Equivalent Internal ESD Circuitry Relative to a Typical Circuit Application

An ESD event produces a short-duration, high-voltage pulse that is transformed into a short-duration, high-

current pulse while discharging through a semiconductor device. The ESD protection circuits are designed to

provide a current path around the operational amplifier core to prevent damage. The energy absorbed by the

protection circuitry is then dissipated as heat.

When an ESD voltage develops across two or more amplifier device pins, current flows through one or

more steering diodes. Depending on the path that the current takes, the absorption device may activate. The

absorption device has a trigger or threshold voltage that is above the normal operating voltage of the OPAx189

but below the device breakdown voltage level. When this threshold is exceeded, the absorption device quickly

activates and clamps the voltage across the supply rails to a safe level.

When the operational amplifier connects into a circuit (as shown in Figure 8-4), the ESD protection components

are intended to remain inactive and do not become involved in the application circuit operation. However,

OPA189, OPA2189, OPA4189

SBOS830I – SEPTEMBER 2017 – REVISED OCTOBER 2021

www.ti.com

Submit Document Feedback

Product Folder Links: OPA189 OPA2189 OPA4189

OPAX189 데이터시트(PDF) 24 Page - Texas Instruments

OPAX189 데이터시트(HTML) 24 Page - Texas Instruments

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52

데이터시트 다운로드

링크 URL