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TLV170, TLV2170, TLV4170

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SBOS782A – NOVEMBER 2016 – REVISED MAY 2018

Product Folder Links: TLV170 TLV2170 TLV4170

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Copyright © 2016–2018, Texas Instruments Incorporated

9 Power Supply Recommendations

The TLVx170 is specified for operation from 2.7 V to 36 V (±1.35 V to ±18 V); many specifications apply from

–40°C to +125°C. Parameters that can exhibit significant variance with regard to operating voltage or

temperature are presented in the Typical Characteristics: Table of Graphs section.

CAUTION

Supply voltages larger than 40 V can permanently damage the device; see the

Absolute Maximum Ratings.

Place 0.1-μF bypass capacitors close to the power-supply pins to reduce errors coupling in from noisy or high-

impedance power supplies. For more detailed information on bypass capacitor placement, see the Layout

section.

10 Layout

10.1 Layout Guidelines

For best operational performance of the device, use good printed-circuit board (PCB) layout practices, including:

•

Noise can propagate into analog circuitry through the power pins of the circuit as a whole and the op amp

itself. Bypass capacitors are used to reduce the coupled noise by providing low-impedance power

sources local to the analog circuitry.

–

Connect low-ESR, 0.1-µF ceramic bypass capacitors between each supply pin and ground, placed as

close to the device as possible. A single bypass capacitor from V+ to ground is applicable for single-

supply applications.

•

Separate grounding for analog and digital portions of circuitry is one of the simplest and most-effective

methods of noise suppression. One or more layers on multilayer PCBs are usually devoted to ground

planes. A ground plane helps distribute heat and reduces EMI noise pickup. Make sure to physically

separate digital and analog grounds, paying attention to the flow of the ground current.

•

In order to reduce parasitic coupling, run the input traces as far away from the supply or output traces as

possible. If these traces cannot be kept separate, crossing the sensitive trace perpendicularly is much

better than in parallel with the noisy trace.

•

Place the external components as close to the device as possible. As illustrated in Figure 34, keeping RF

and RG close to the inverting input minimizes parasitic capacitance.

•

Keep the length of input traces as short as possible. Always remember that the input traces are the most

sensitive part of the circuit.

•

Consider a driven, low-impedance guard ring around the critical traces. A guard ring can significantly

reduce leakage currents from nearby traces that are at different potentials.