1 Features

• ±50-V operating voltage, ±55-V absolute maximum

• Integrated fixed bipolar 32-mA current limit

• Allows 2x current limit at start-up

• 50% space savings compared to a typical discrete

protection circuit

• Low R-on: 7.5-Ω typical

• Low IQ (< 100 nA) – current drawn from loop when

powered from external supply

• Protection against miswiring conditions on IN and

OUT

• Protection during signal line surge IEC61000-4-5

(with external TVS)

• Criteria-A EFT (IEC61000-4-4) immunity (with

external TVS)

• Supports loop testing without supply (TPS26610

only)

• HART compliant

• Enable control

• SGOOD for system health monitoring

• Thermal shutdown

2 Applications

• Factory automation and control – PLCs - analog

input and output module

• Motor drives control

• HART inputs

• HVAC controllers

• UART IO protection

• Thermal controller

3 Description

The TPS2661x is a compact, feature-rich, fully

integrated current loop protector suitable for analog

inputs, analog outputs, sensor transmitters, HART

inputs, and UART IO protection. The device provides

universal input protection for ±20 mA, 0 mA to 20 mA,

and 4 mA–20 mA. Low RON values of 7.5 Ω minimizes

drop in the current loop, thereby extending operating

range and supporting operation even with lower

voltage power supplies. The device can withstand and

protect the loads from positive and negative supply

voltages up to ±50 V. The MODE pin allows flexibility

to enable 2x current limit through the device to enable

proper start-up of two wire transmitters. Device is

capable of operating from an external bipolar supply

as low as ± 2.25 V to ±20 V. The device can also

be powered from unipolar supplies as low as 3 V

to 30 V. The TPS26610 and TPS26613 feature loop

power mode to facilitate loop testing in un-powered

state without ±Vs supplies.

The device also protects the system from output side

miswiring in analog outputs and sensor transmitters

by turning off the current path. The internal robust

protection control blocks along with the 50-V rating

of the TPS2661x help to protect against surge

(IEC61000-4-5) and EFT (IEC61000-4-4) transients

for signal lines. The device greatly reduces system

footprint by its 2.9-mm × 1.6-mm 8-pin SOT-23

package.