Power-Supply

ESD Cell

250

Ÿ

250

Ÿ

IN

±

IN+

TVS

+

±

TVS

+

Copyright © 2016, Texas Instruments Incorporated

10

OPA1692, OPA1694

SBOS566 – JUNE 2017

www.ti.com

Product Folder Links: OPA1692 OPA1694

Submit Documentation Feedback

Copyright © 2017, Texas Instruments Incorporated

Feature Description (continued)

The OPA169x family of amplifiers uses a propriety technology to reduce signal distortion that does not increase

the power-supply current. The distortion cancellation technique reduces odd-order harmonic distortion, which is

produced by the input transistor pair of the amplifier. As Figure 8 illustrates, the impact to THD+N is significant,

especially at high frequencies where the OPA169x devices exhibit over 30-dB lower distortion than competitor

amplifiers at similar power-supply current levels.

7.3.2 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 can 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 them from

accidental ESD events both before and during product assembly.

A good understanding of this basic ESD circuitry and its relevance to an electrical overstress event is helpful.

Figure 9 illustrates the ESD circuits contained in the OPA169x (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.

Figure 9. 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 when 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.