STMicroelectronics STLM20DD9F

Overview

STLM20DD9F from STMicroelectronics is a precision analog-output temperature sensor in UDFN-4L package, delivering ±1.5 °C max accuracy at 25 °C, ultra-low 4.8 µA typical quiescent current, and operation from 2.4 V to 5.5 V across –40 °C to 85 °C. It serves as a battery-life-critical thermal monitor in portable RF power stages and voltage-controlled crystal oscillators.

For engineers reviewing the STLM20DD9F datasheet, STLM20DD9F pinout, STLM20DD9F application, or STLM20DD9F equivalent, key selection criteria include its 160 Ω output impedance, ±0.5 °C typical accuracy at 25 °C, grade-9 temperature range, UDFN-4L footprint compatibility, and linear transfer function slope of –11.77 mV/°C.

Technical Context

The STLM20DD9F implements a bandgap-based analog voltage output with second-order parabolic transfer function (VO = –3.88×10⁻⁶·T² – 1.15×10⁻²·T + 1.8639 V), optimized for grade-9 operation (–40 °C to 85 °C). Its output exhibits ±1.00 °C error at 80–85 °C and ±0.5 °C at 25–30 °C under 2.7 V supply.

No internal digital interface or ADC is present; it functions as a passive analog transducer requiring external ADC sampling. Self-heating is negligible due to 8 µA max IQ, and output remains stable up to 300 pF capacitive load without external filtering.

Key Specifications

Pinout & Package

STLM20DD9F uses the UDFN-4L (1.00 mm × 1.30 mm) 4-lead package with wettable flank terminations, optimized for space-constrained portable PCBs and automated optical inspection.

Key Features

Applications

Equivalent & Alternatives

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

Compared with LM75BIMM/NOPB and TSI721AIDT, STLM20DD9F uniquely balances ultra-low IQ (4.8 µA), grade-9 thermal validation, and UDFN-4L miniaturization-making it optimal for space- and battery-constrained analog-sensing roles where digital overhead or self-heating cannot be tolerated.

Availability

STLM20DD9F is available at Aetrix Electronics and suitable for smartphone thermal management, RF power transistor monitoring, voltage-controlled crystal oscillator compensation, and portable medical instrument design requiring stable component supply and ECOPACK® tape-and-reel delivery.

Supply support for STLM20DD9F 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

STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing microcontrollers, power management ICs, sensors, and analog products for industrial, automotive, and consumer markets.

The STLM20 series belongs to ST's precision analog sensor product line, engineered specifically for ultra-low-power, high-accuracy thermal monitoring in battery-operated portable electronics.

FAQ

What is the maximum capacitive load the STLM20DD9F can drive without oscillation?

The STLM20DD9F is characterized to remain stable with capacitive loads up to 300 pF across its full operating temperature and supply range. Beyond this, a low-pass RC filter (e.g., 200 Ω + 1 µF) is recommended per Figure 3 to suppress high-frequency noise while preserving thermal response time.

Does the NC pin on the UDFN-4L package require termination?

No-the NC pin on STLM20DD9F must be left electrically floating and unconnected. Datasheet Figure 2 and Table 1 explicitly state "NC should be left floating or grounded", but grounding is prohibited per ST's design guidance to avoid parasitic coupling and thermal path disruption.

Can STLM20DD9F operate reliably at 2.4 V supply across its full –40 °C to 85 °C range?

Yes-ST specifies 2.4 V minimum supply for grade-9 operation. At 2.4 V, the device maintains full functionality and accuracy specs (±1.5 °C max) across –40 °C to 85 °C, though output voltage headroom decreases slightly versus 2.7 V operation per Table 4.

How does the STLM20DD9F's output voltage scale with temperature?

VOUT follows a second-order parabolic relationship: VO = (–3.88×10⁻⁶)·T² + (–1.15×10⁻²)·T + 1.8639 V. At 0 °C it outputs 1.864 V, decreasing to ~0.859 V at 85 °C-a nominal slope of –11.77 mV/°C-enabling accurate linear approximation over limited ranges.