Texas Instruments LM4040D41IDCKR

Overview

LM4040D41IDCKR from Texas Instruments is a precision micropower shunt voltage reference with a fixed 4.096V output, D-grade (±1.0% initial tolerance, 150ppm/°C tempco), rated for –40°C to 85°C operation, and packaged in a 5-pin SC-70 (DCK) package. It delivers stable reference voltage in low-current analog signal chains such as 12-bit ADC biasing and industrial sensor front-ends.

For engineers reviewing the LM4040D41IDCKR datasheet, LM4040D41IDCKR pinout, LM4040D41IDCKR application, or LM4040D41IDCKR equivalent, key selection criteria include cathode current range (45μA–15mA), dynamic impedance (≤1.1Ω), wide-temp stability, no-output-capacitor operation, and SC-70 footprint compatibility with space-constrained PCB layouts.

Technical Context

The LM4040D41IDCKR operates as a two-terminal shunt reference: cathode sinks current while anode connects to system ground, enabling simple series-resistor biasing. Its Zener-zap trimmed reverse breakdown ensures precise 4.096V regulation without external components.

It achieves low-noise performance (35μVRMS, 10Hz–10kHz) and thermal hysteresis of only 0.08%, supporting high-resolution data acquisition where long-term drift and noise floor directly impact measurement fidelity.

Key Specifications

Pinout & Package

LM4040D41IDCKR uses the 5-pin SC-70 (DCK) package (2.00mm × 1.25mm). Pins 4 and 5 are No Connect (NC); functional terminals are Cathode (Pin 3), Anode (Pin 1), and the optional floating/stabilization pin (Pin 2).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar shunt voltage reference applications.

Compared with TL4050C41IDBZR and MAX6008AEUR+T, the LM4040D41IDCKR trades initial accuracy for lower minimum current (45μA vs. ≥60μA/≥75μA) and includes a dedicated EMI stabilization pin - making it optimal for ultra-low-power, high-noise industrial edge nodes where layout flexibility matters.

Availability

LM4040D41IDCKR is available at Aetrix Electronics and suitable for industrial sensor front-ends, field transmitters, and energy infrastructure monitoring requiring stable component supply and long-lifecycle support.

Supply support for LM4040D41IDCKR 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

Texas Instruments is a global semiconductor leader specializing in analog and embedded processing technologies, with decades of expertise in precision reference design and industrial-grade reliability.

The LM4040 series was engineered specifically for cost-sensitive, space-constrained industrial and instrumentation applications demanding micropower operation, capacitor-free stability, and robust temperature performance - not general-purpose or consumer-grade use.

FAQ

What is the minimum cathode current required for stable regulation of the LM4040D41IDCKR?

The LM4040D41IDCKR requires a minimum cathode current of 45μA (typical) at 25°C to maintain regulation within specification. At full temperature range (–40°C to +85°C), the guaranteed minimum is 80μA. Below this threshold, output voltage may deviate beyond the ±1.0% initial tolerance band. This low current enables use in battery-powered field sensors where quiescent power must remain under 200μW.

Can the LM4040D41IDCKR operate without an output capacitor?

Yes, the LM4040D41IDCKR is explicitly designed to be stable with all capacitive loads and requires no output capacitor for operation. Its internal architecture provides inherent phase margin across 0–10μF load capacitance, eliminating the need for external decoupling and reducing bill-of-materials cost and PCB area - a key advantage over many competing shunt references that mandate minimum 1nF bypassing.

What is the purpose of Pin 2 on the LM4040D41IDCKR SC-70 package?

Pin 2 on the LM4040D41IDCKR is a dedicated stabilization terminal. It must either float or be connected directly to the Anode (Pin 1). TI recommends connecting it to Anode in high-EMI environments - such as near transformers or switch-mode power supplies - to reduce susceptibility to high-frequency noise coupling into the reference node, thereby preserving output voltage accuracy under noisy conditions.

How does the LM4040D41IDCKR's 150ppm/°C temperature coefficient impact system accuracy?

The LM4040D41IDCKR's maximum 150ppm/°C temperature coefficient introduces up to ±0.614mV/°C drift from nominal 4.096V. Over its full –40°C to +85°C range (ΔT = 125°C), total drift is bounded at ±0.768V (±18.8%). In practice, system-level calibration at two temperatures can reduce residual error to <±0.05% - sufficient for 12-bit measurement systems where end-point calibration is standard practice.

Is the LM4040D41IDCKR pin-compatible with other LM4040 variants in the SC-70 package?

Yes, all LM4040x41IDCKR variants (A/B/C/D grades, 4.096V output) share identical SC-70-5 pinout and footprint. The only differences are initial tolerance (0.1% to 1.0%) and temperature coefficient (100ppm/°C or 150ppm/°C), allowing drop-in replacement during design iteration or cost optimization without PCB revision - provided the application's accuracy and drift requirements align with the selected grade.