Analog Devices Inc. LT3092EST#PBF

LT3092EST#PBF Programmable Current Source Product Summary

The LT3092EST#PBF from Analog Devices is a high-precision, two-terminal adjustable current source regulator designed for easy implementation in a wide range of analog applications. Delivering output currents from 0.5mA up to 200mA with merely two external resistors, the LT3092EST#PBF combines simplicity with high performance for engineers tasked with sourcing precise currents. Its wide 1.2V to 40V input voltage range and surface-mount SOT-223-3 package lend versatility for integration into both compact and robust designs. As part of the LT3092 series, this device offers robust programmability and accuracy, making it a key component for current regulation in various demanding electronics applications.

Highlights and Functional Specifications of the LT3092EST#PBF

At the heart of the LT3092EST#PBF is a programmable current source configuration that simplifies current regulation. Output current is set by the ratio of two resistors, covering a broad range from 0.5mA to 200mA. The device operates without the need for input or output capacitors, supporting minimal-intrusion designs and offering high input/output impedance. Fast and accurate current programming is enabled by the 1% initial set pin current accuracy, and line regulation is typically less than 0.001%/V, ensuring stable operation even under fluctuating supply voltages.

With reverse-voltage and reverse-current protection, as well as integrated current limiting and thermal shutdown, the LT3092EST#PBF is particularly suited for environments where reliability and safety are crucial. The regulator’s DC and AC impedance stability lends itself to both precision and intrinsic safety circuits, making it well-matched for industrial and automotive systems.

Electrical Specifications and Performance Metrics of the LT3092EST#PBF

The LT3092EST#PBF demonstrates outstanding electrical performance. The programmable current is controlled via the SET pin, which features a nominal 10μA current with outstanding thermal and line stability. Offset voltage between OUT and SET is typically ±2mV, with negligible drift over temperature and load.

The minimum load current, which is equal to the device’s quiescent current, ranges from 300μA to 500μA. Dropout voltage varies from 1.22V at 10mA load to a maximum of 1.65V at full 200mA load. The current limit provides robust protection, set between 200mA and 300mA for input voltages up to 5V.

Noise performance is another highlight: reference current RMS output noise is only 0.7nARMS (measured between 10Hz and 100kHz), with ripple rejection exceeding 90dB at 120Hz with appropriate external capacitance (0.1μF at SET and 2.2μF at OUT). Such features qualify the LT3092EST#PBF for applications where ultralow noise and clean current delivery are essential.

LT3092EST#PBF Pin Configuration and Package Selections

The LT3092EST#PBF is delivered in the industry-standard 3-lead SOT-223 package, favoring thermal management and straightforward PCB layout. The pinout comprises IN (input supply), OUT (current source output), and SET (current programming input). The exposed pad/tab is internally connected to OUT and should be tied to the corresponding OUT pin on the PCB to optimize thermal performance.

For higher integration flexibility, the LT3092 series is also available in 8-lead DFN and 8-lead TSOT-23 packages, all of which are RoHS 3 compliant and rated for automotive and industrial temperature ranges (-40°C to 125°C, with a military grade down to -55°C).

Implementation and Common Usage Examples of the LT3092EST#PBF

The LT3092EST#PBF’s two-terminal current source operation allows it to be placed in series with signal lines, providing stable bias or supply currents to remote sensors—especially where long cable runs or intrinsic safety are required. It is commonly found in sensor excitation circuits, ground-referenced or floating current sources, and adjustable current limiting roles for power supply rails. Because of the inherent simplicity and lack of required capacitors, it excels in space-constrained designs such as portable test equipment, instrumentation, and distributed sensing systems.

In precision analog signal chains, the LT3092EST#PBF can provide bias currents to photodiodes or other sensors where accuracy, low noise, and stability are paramount. Its wide operating voltage and tight regulation make it ideal for both localized and remote analog subsystems. Automotive engineers can leverage its AEC-Q100 qualification in safety-critical and harsh-environment applications.

LT3092EST#PBF Safety and Protection Capabilities

The LT3092EST#PBF incorporates robust protection mechanisms, including reverse-battery and reverse-current protection, to prevent damage during mis-wiring or cable faults. The integrated current limit circuit prevents damage from overcurrent situations, while the thermal shutdown facility ensures the device is protected against over-temperature events.

These features not only enhance device ruggedness in the field but also simplify design of compliance circuits for global safety standards. The result is a programmable current source that supports extended lifetime and minimal maintenance, even in deployments with infrequent manual inspection.

Alternative and Substitute Models Comparable to LT3092EST#PBF

When considering design alternatives or second sources, engineers may evaluate similar two-terminal programmable current sources or current-regulating diodes that fit the voltage and current envelope required by the application. Candidates may include:

The LT3092 series family in alternative packages (e.g., LT3092IDD#PBF in DFN, LT3092ETS8#PBF in TSOT-23) for different thermal or PCB constraints.

Comparable current source ICs from Analog Devices or other manufacturers if a broader input voltage or current setting range is needed, or if form factor and regulatory certifications differ.

For applications with less stringent accuracy or protection requirements, general-purpose current regulators may suffice, though with tradeoffs in noise and regulation.

Compatibility and performance should be carefully verified in the specific design context, as offsets in accuracy, protection level, and noise can have system-level impacts.

Conclusion

: Evaluating the LT3092EST#PBF for Precision Current Source Applications

Analog Devices’ LT3092EST#PBF stands out as a versatile, high-precision programmable current source tailored to the demanding needs of modern analog, industrial, and automotive electronics. Its straightforward programmability, wide input range, and robust protection enable selection engineers to implement reliable current regulation with minimal component count. By understanding its differentiating features, application contexts, and comparison to equivalent models, engineers and procurement specialists can make informed decisions that enhance circuit performance and reliability across a spectrum of current source requirements.