Analog Devices Inc. LTC2055IDD#PBF

Overview

LTC2055IDD#PBF from Analog Devices (formerly Linear Technology) is a dual, micropower, zero-drift operational amplifier in an 8-lead 3mm × 3mm DFN package, rated for –40°C to 85°C operation. It delivers 3μV max input offset voltage, 30nV/°C max drift, 130μA per amplifier supply current, and rail-to-rail output swing - enabling high-accuracy signal conditioning in precision sensor interfaces and battery-powered instrumentation.

For engineers reviewing the LTC2055IDD#PBF datasheet, LTC2055IDD#PBF pinout, LTC2055IDD#PBF application, or LTC2055IDD#PBF equivalent, key selection criteria include guaranteed industrial-temperature zero-drift performance, ultra-low 1.6μV_P-P (DC–10Hz) noise, 500kHz gain-bandwidth product, and compatibility with single-supply (2.7V–6V) or split-supply (±2.5V) configurations in space-constrained layouts.

Technical Context

The LTC2055IDD#PBF employs auto-zeroing architecture with a 1kHz internal clock to continuously correct input offset and drift, achieving near-zero DC error across temperature, supply, and common-mode voltage variations. Its input stage supports rail-to-rail common-mode range (V_– to V₊ – 0.5V) and features 1pA typical input bias current at 25°C.

It integrates two independent amplifiers sharing only power rails and substrate; each exhibits 140dB typical open-loop gain, 130dB PSRR and CMRR, and 0.5V/μs slew rate. The DFN package's exposed V_– pad improves thermal performance (θ_JA = 160°C/W) and reduces ground noise coupling in sensitive analog circuits.

Key Specifications

Pinout & Package

Package: 8-lead (3mm × 3mm × 0.8mm) plastic DFN (DD), exposed metal pad internally connected to V_–; RoHS-compliant, lead-free finish.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar precision op amp applications.

Compared with AD8628ARZ and LTC2055IMS8#PBF, the LTC2055IDD#PBF uniquely combines dual-channel integration, 130μA/channel quiescent current, and DFN thermal efficiency - making it optimal for miniaturized, battery-operated precision instruments where board area and self-heating are constrained.

Availability

LTC2055IDD#PBF is available at Aetrix Electronics and suitable for thermocouple amplification, electronic scale interfaces, medical ECG front-ends, battery-powered data loggers, and precision current sensing requiring stable component supply across extended temperature ranges.

Supply support for LTC2055IDD#PBF includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.

Manufacturer

Analog Devices, Inc. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors.

The LTC2055 belongs to Linear Technology's precision zero-drift op amp family, engineered for applications demanding uncompromised DC accuracy, ultra-low noise, and robust operation in harsh thermal environments - especially sensor signal chains and portable instrumentation.

FAQ

What is the maximum operating temperature range for the LTC2055IDD#PBF?

The LTC2055IDD#PBF is specified for operation from –40°C to +85°C ambient temperature. This industrial-grade rating is guaranteed per the datasheet's LTC2055I temperature grade, and applies across all key DC parameters including input offset voltage, drift, and supply current. The DFN package's thermal resistance (θ_JA = 160°C/W) supports reliable operation at the upper limit with appropriate PCB copper area.

Does the LTC2055IDD#PBF require external capacitors for stability?

No, the LTC2055IDD#PBF is unity-gain stable and does not require external compensation capacitors. Its internal compensation ensures stability with capacitive loads up to 100pF and resistive feedback networks. However, a 0.1μF ceramic capacitor between V₊ and V_– pins (close to the device) is mandatory for PSRR integrity and noise suppression, as confirmed in the datasheet's test circuits and layout guidelines.

How does the auto-zeroing clock affect signal integrity in the LTC2055IDD#PBF?

The LTC2055IDD#PBF uses a 1kHz internal auto-zeroing clock, producing two forms of clock feedthrough: input-referred residue (<0.2μV_RMS) and charge-injection–induced spikes. The latter is minimized by keeping input source impedance <10kΩ. In precision DC applications, this manifests as negligible 1kHz tone in FFTs - far below the 1.6μV_P-P broadband noise floor - and does not impact static accuracy.

Can the LTC2055IDD#PBF drive ADC inputs directly?

Yes, the LTC2055IDD#PBF can directly drive SAR and delta-sigma ADC inputs due to its rail-to-rail output swing, low output impedance (<1Ω typical), and ability to settle to 16-bit accuracy within 5μs. When interfacing with switched-capacitor ADCs, a small series resistor (10–50Ω) is recommended to isolate the op amp from capacitive kickback, preserving THD and SNR performance.

Is the exposed pad on the LTC2055IDD#PBF's DFN package electrically connected?

Yes, the exposed metal pad on the bottom of the LTC2055IDD#PBF's DD package is internally connected to the V_– pin. It must be soldered to a PCB copper pour tied to the system ground plane to ensure proper thermal dissipation (reducing θ_JA by up to 40°C/W) and to minimize ground noise coupling into the sensitive analog inputs.