Texas Instruments LM20BIM7

Overview

LM20BIM7 from Texas Instruments (formerly National Semiconductor) is a precision analog-output CMOS temperature sensor in SC70-5 package, operating from +2.4 V to +5.5 V with ±2.5°C accuracy over −55°C to +130°C (at V+ ≥ 2.7 V), 10 μA max quiescent current, and parabolic transfer function VO = (−3.88×10⁻⁶×T²) + (−1.15×10⁻²×T) + 1.8639 V - used for battery-powered thermal monitoring in cellular phones and power supply modules.

For engineers reviewing the LM20BIM7 datasheet, LM20BIM7 pinout, LM20BIM7 application, or LM20BIM7 equivalent, this page delivers verified specifications, SC70-5 terminal mapping, real-world use cases in Li-ion-powered systems, and two validated alternative parts with documented functional trade-offs.

Technical Context

The LM20BIM7 implements a monolithic silicon bandgap-based temperature-to-voltage transducer with inherent parabolic curvature, enabling ±1.5°C error at +30°C and ±2.5°C at temperature extremes. Its output impedance is ≤160 Ω, supporting direct interface to 12-bit ADCs without buffering.

Thermal self-heating is limited to <0.02°C in still air due to sub-10 μA quiescent current, and GND pin (Pin 2) serves as both electrical reference and primary thermal conduction path to PCB ground plane - critical for accurate surface-temperature measurement.

Key Specifications

Pinout & Package

LM20BIM7 uses the SC70-5 (NS Package MAA05A) surface-mount package: 2.0 mm × 2.1 mm footprint, 0.65 mm pitch, 0.9 mm height, with exposed die pad thermally coupled to Pin 2 (GND).

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar analog-output temperature sensor applications.

Compared with LM20CIM7, LM20BIM7 provides tighter accuracy for thermal safety-critical functions; compared with TS2012-1.8, it supports higher supply voltages without level-shifting but requires ≥2.4 V - making LM20BIM7 optimal for 3.3 V/5 V systems needing proven industrial-range reliability.

Availability

LM20BIM7 is available at Aetrix Electronics and suitable for cellular phone thermal management, Li-ion battery pack monitoring, and industrial power supply modules requiring stable component supply across extended temperature ranges and long production lifecycles.

Supply support for LM20BIM7 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 acquired National Semiconductor in 2011 and maintains its precision analog portfolio, including temperature sensors, with full backward compatibility and long-term product support.

The LM20 series was designed specifically for ultra-low-power, high-accuracy analog temperature sensing in space-constrained portable and industrial systems - emphasizing SC70 packaging, sub-10 μA operation, and full −55°C to +130°C validation.

FAQ

What is the maximum operating temperature range for LM20BIM7 when powered at +2.4 V?

At +2.4 V supply, the LM20BIM7 operates from −30°C to +130°C. The negative limit degrades from −55°C (at ≥2.7 V) due to reduced internal bias headroom - confirmed in TI's LM20 datasheet Section "Operating Ratings". This behavior is intrinsic to the bandgap reference design and applies exclusively to LM20BIM7 under 2.4 V conditions.

Does LM20BIM7 require external calibration to achieve ±2.5°C accuracy?

No, LM20BIM7 achieves ±2.5°C accuracy over −55°C to +130°C without user calibration - this specification is factory-tested and guaranteed per TI's LM20BIM7 ordering information table. The parabolic transfer function VO = (−3.88×10⁻⁶×T²) + (−1.15×10⁻²×T) + 1.8639 V is laser-trimmed during production, and the ±2.5°C limit includes curvature error, nonlinearity, and thermal hysteresis.

Can LM20BIM7 drive an ADC input directly without a buffer amplifier?

Yes, LM20BIM7 can drive most 12-bit SAR ADC inputs directly: its 160 Ω max output impedance and ±2.5 mV load regulation error (for IL ≤ +16 μA) ensure <0.1 LSB error at 3.3 V full-scale. TI's Application Note SNAA123 confirms successful interface to ADS7822 and similar converters - no buffer needed unless ADC input capacitance exceeds 300 pF.

Is LM20BIM7 susceptible to light-induced errors, and how is this mitigated?

Only the micro SMD variant (LM20SITL) exhibits light sensitivity - LM20BIM7 uses opaque SC70-5 plastic packaging and shows no measurable light-induced voltage shift. TI's LM20 datasheet Section 4 explicitly states light sensitivity applies solely to the micro SMD package; LM20BIM7 is immune and requires no light shielding in optical environments.

What is the thermal resistance θJA for LM20BIM7 in SC70-5 package on standard FR-4 PCB?

LM20BIM7 has θJA = 415°C/W in still air with no heat sink, measured per JEDEC JESD51-2 on a 1-inch² copper pad (TI LM20 datasheet Section "Thermal Resistance"). This value assumes the GND pin (Pin 2) is soldered to a solid 1-oz copper plane - reducing θJA to 350°C/W with a small heat sink. Self-heating remains <0.02°C at 10 μA, making thermal design straightforward.