My Inquiry
My Account
Texas Instruments LM385MX-1.2/NOPB
- Part No.:
- LM385MX-1.2/NOPB
- Manufacturer:
- Texas Instruments
- Category:
- Voltage Reference
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
LM385MX-1.2/NOPB.pdf
- Description:
- IC VREF SHNT -2.43%/+2.02% 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:13,959
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM385MX-1.2/NOPB from Texas Instruments is a micropower 2-terminal band-gap voltage reference diode delivering a precise 1.235 V output with ±1% initial tolerance, 1 Ω dynamic impedance, and 150 ppm/°C temperature coefficient over 0°C to 70°C. It operates from 10 μA to 20 mA reverse current and is used in battery-powered precision analog circuits such as portable meters and low-power thermometers.
For engineers reviewing the LM385MX-1.2/NOPB datasheet, LM385MX-1.2/NOPB pinout, LM385MX-1.2/NOPB application, or LM385MX-1.2/NOPB equivalent, key selection criteria include its SOIC-8 package, micropower operation down to 10 μA, tight initial voltage tolerance, low dynamic impedance, and compatibility with capacitive loading in compact reference designs.
Technical Context
The LM385MX-1.2/NOPB implements a band-gap reference architecture using on-chip trimmed transistors and resistors to achieve stable 1.235 V output across its 10 μA–20 mA operating current range. Its design eliminates need for external compensation, enabling direct use with capacitive loads up to several microfarads without oscillation.
It features exceptionally low wideband noise (60 μVrms, 10 Hz–10 kHz) and long-term stability of 20 ppm over 1000 hours at 25°C. The device is not a regulator IC but functions as a 2-terminal shunt reference, requiring an external current source for biasing and load regulation.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage | 1.235 V nominal; tight ±1% initial tolerance enables high-accuracy ADC/DAC biasing without trimming. |
| Initial Tolerance | ±1% at 25°C; ensures predictable system offset without calibration in cost-sensitive instrumentation. |
| Operating Current | 10 μA to 20 mA reverse current; supports ultra-low-power sensor interfaces and extends battery life in portable devices. |
| Dynamic Impedance | 1 Ω at 100 μA; maintains stable output under varying load conditions and minimizes error in precision current sources. |
| Temp Coefficient | 150 ppm/°C max; provides predictable drift over 0°C–70°C industrial range for reliable performance in uncontrolled environments. |
| Wideband Noise | 60 μVrms (10 Hz–10 kHz); low enough to avoid degrading resolution in 12-bit+ data acquisition systems. |
| Long-Term Stability | 20 ppm over 1000 hours; reduces recalibration frequency in field-deployed measurement equipment. |
Pinout & Package
LM385MX-1.2/NOPB is housed in an 8-pin SOIC package (Package Drawing D), with pins 1–8 arranged linearly. Pin 1 is index-marked; pins 4 and 5 are internally connected to the die attach pad and must be tied to pin 2 (cathode) or left floating per TI's recommended layout.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 | Anode (input) | Connects to current source; reverse-biased operation requires external resistor or active current sink. |
| Pin 2 | Cathode (output) | Provides regulated 1.235 V reference; serves as return path for load current and bias current. |
| Pins 4 & 5 | Die Attach Pad (DAP) | Internally connected to cathode; recommended to tie to pin 2 for thermal and electrical stability. |
| Pins 3, 6–8 | No Connect (NC) | Not bonded; must remain unconnected to avoid parasitic coupling or latch-up risk. |
Key Features
| Feature | Design Value |
|---|---|
| Capacitive Load Tolerance | Stable with >1 μF output capacitance-eliminates need for series isolation resistor in battery-powered references. |
| Micropower Operation | Functional down to 10 μA reverse current-enables use in energy-harvesting and coin-cell applications. |
| Low Dynamic Impedance | 1 Ω typical-minimizes output voltage shift when driving variable analog loads like op-amp inputs. |
| On-Chip Trimmed Voltage | Factory-trimmed to ±1%-reduces BOM count and board space vs. discrete Zener + op-amp solutions. |
| Low Temperature Drift | 150 ppm/°C max-ensures <±1.5 mV total drift across 0°C–70°C, critical for unheated industrial sensors. |
Applications
| Portable Digital Multimeter | Low-Power Thermometer |
|---|---|
Use Scenario: Handheld DMM requiring stable 1.235 V reference for 3½-digit ADC conversion powered by a single 9 V alkaline battery. IC Role / Device Role / Timing Role: 2-terminal shunt voltage reference providing excitation for ADC internal reference buffer and scaling network. Use Value: Enables >100-hour battery life while maintaining ±0.1% full-scale accuracy across temperature due to low 10 μA quiescent current and 150 ppm/°C drift. | Use Scenario: Battery-operated clinical thermometer measuring 35°C–42°C with 0.1°C resolution using a thermistor bridge. IC Role / Device Role / Timing Role: Precision voltage reference establishing known bias point for Wheatstone bridge excitation and ratiometric ADC measurement. Use Value: Delivers stable 1.235 V with <±1.2 mV total error over operating range, eliminating need for software calibration and reducing firmware complexity. |
| Micropower Current Source | Low-Voltage Sensor Interface |
Use Scenario: 1 μA–1 mA programmable current source for gas sensor biasing in IoT environmental monitors powered by CR2032 cells. IC Role / Device Role / Timing Role: Shunt reference setting precise voltage across sense resistor to generate accurate output current via op-amp feedback. Use Value: 1 Ω dynamic impedance ensures current accuracy remains within ±0.5% despite supply variations and load capacitance up to 100 nF. | Use Scenario: Signal conditioning front-end for MEMS pressure sensor with 0.5 V full-scale output, interfaced to 1.8 V microcontroller ADC. IC Role / Device Role / Timing Role: Reference voltage source for rail-to-rail op-amp gain stage and ADC reference input in sub-2 V systems. Use Value: Operates reliably at 10 μA bias current and delivers 1.235 V with <10 μV noise-preserving SNR in 14-bit sensor digitization. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt voltage reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM385BZ-1.2/NOPB | TO-92 package, 3-pin, same 1.235 V ±1% spec, but rated for 0°C–70°C and higher thermal resistance (440°C/W). | Suitable for through-hole prototyping or low-volume PCBs where SOIC reflow is unavailable. | Select when manual assembly, thermal budget allows higher junction temp, or legacy TO-92 footprint is required. |
| REF3012AIDBZR | 1.2 V output, ±0.2% initial tolerance, 50 ppm/°C drift, SOT-23-3, 50 μA min operating current. | Better accuracy and drift, but higher minimum current limits use in <50 μA systems. | Choose for higher-precision applications where tighter tolerance and lower drift justify increased quiescent current. |
Compared with LM385BZ-1.2/NOPB, LM385MX-1.2/NOPB offers superior thermal performance in SOIC-8 (θJA = 165°C/W vs. 440°C/W) and better manufacturability; versus REF3012AIDBZR, it trades 0.2% tolerance and 50 ppm/°C drift for 10 μA operation and lower cost in volume production.
Availability
LM385MX-1.2/NOPB is available at Aetrix Electronics and suitable for portable instrumentation, battery-powered sensors, and low-power analog signal chains requiring stable component supply with RoHS-compliant, lead-free packaging and consistent SOIC-8 form factor.
Supply support for LM385MX-1.2/NOPB 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 high-reliability manufacturing.
The LM385MX-1.2/NOPB belongs to TI's micropower shunt voltage reference family, engineered specifically for battery-constrained, space-limited applications demanding stable 1.235 V with minimal quiescent current and robust capacitive-load immunity.
FAQ
What is the exact reference voltage and tolerance of LM385MX-1.2/NOPB?
The LM385MX-1.2/NOPB delivers a nominal reference voltage of 1.235 V with ±1% initial tolerance at 25°C, verified across production lots per TI's SNVS742E datasheet. This value is guaranteed over the full 10 μA–20 mA operating current range and remains stable under capacitive loading, making LM385MX-1.2/NOPB suitable for precision analog designs where absolute voltage accuracy is critical.
Can LM385MX-1.2/NOPB operate from a 1.5 V battery?
Yes, LM385MX-1.2/NOPB can operate from a 1.5 V battery when configured as a shunt reference with appropriate current limiting. Its 1.235 V breakdown voltage allows ~265 mV headroom, enabling stable regulation even as the battery discharges to ~1.3 V. Figure 16 in the TI datasheet explicitly demonstrates this configuration, confirming LM385MX-1.2/NOPB functionality down to 1.3 V supply with ~20 μA standby current.
What is the maximum operating temperature range for LM385MX-1.2/NOPB?
The LM385MX-1.2/NOPB is rated for operation from 0°C to +70°C ambient temperature, as specified in TI's official package addendum and electrical characteristics table. This industrial-grade range aligns with its SOIC-8 packaging and distinguishes it from the wider-range LM185-1.2-N (−55°C to +125°C) and LM285-1.2-N (−40°C to +85°C) variants.
Does LM385MX-1.2/NOPB require external compensation for stability?
No, LM385MX-1.2/NOPB does not require external compensation. Its internal band-gap design is inherently tolerant of capacitive loading, remaining stable with output capacitances exceeding 1 μF. This eliminates series resistors or isolation components commonly needed with older references, simplifying layout and improving reliability in LM385MX-1.2/NOPB-based designs.
How does the SOIC-8 package of LM385MX-1.2/NOPB affect thermal performance?
The SOIC-8 package of LM385MX-1.2/NOPB provides a junction-to-ambient thermal resistance (θJA) of 165°C/W, significantly lower than TO-92 alternatives (440°C/W). This enables higher power dissipation at lower temperature rise-critical for sustained operation near 20 mA bias current-and improves long-term stability by reducing thermal stress on the band-gap core in LM385MX-1.2/NOPB applications.
LM385MX-1.2/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Reference Type:
- Shunt
- Output Type:
- Fixed
- Voltage - Output (Min/Fixed):
- 1.235V
- Voltage - Output (Max):
- -
- Current - Output:
- 20 mA
- Tolerance:
- -2.43%, +2.02%
- Temperature Coefficient:
- 150ppm/°C
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- 60µVrms
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 15 µA
- Operating Temperature:
- 0°C ~ 70°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
LM385MX-1.2/NOPB FAQ
1.How can I place an order for LM385MX-1.2/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LM385MX-1.2/NOPB on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for LM385MX-1.2/NOPB reliable?
The price and inventory of LM385MX-1.2/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM385MX-1.2/NOPB is usually 5 days.
3.What payment methods are accepted for LM385MX-1.2/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM385MX-1.2/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM385MX-1.2/NOPB?
LM385MX-1.2/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM385MX-1.2/NOPB order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for LM385MX-1.2/NOPB?
For technical support, including LM385MX-1.2/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM385MX-1.2/NOPB requirements.
6.How does Aetrix verify that LM385MX-1.2/NOPB is sourced from the original manufacturer or authorized distributors?
All LM385MX-1.2/NOPB products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LM385MX-1.2/NOPB meets industry standards.
7.What is the process for return or replacement of LM385MX-1.2/NOPB?
All LM385MX-1.2/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LM385MX-1.2/NOPB, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The LM385MX-1.2/NOPB part is unused and in its original packaging.
Return procedure for LM385MX-1.2/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM385MX-1.2/NOPB Tags
-
TL431AIDBZR
Texas Instruments
-
TL431BQDBZR
Texas Instruments
-
AN431AN-ATRG1
Diodes Incorporated
-
LM4040CYM3-2.5-TR
Microchip Technology
-
LM4040CYM3-4.1-TR
Microchip Technology
-
LM4040EIM3-2.5/NOPB
Texas Instruments
-
AZ431LBNTR-G1
Diodes Incorporated
-
LM4040D20IDBZR
Texas Instruments
-
LM4041DIM3-ADJ/NOPB
Texas Instruments
-
LM4040DIM3X-2.5/NOPB
Texas Instruments
-
LM4040DIM3-2.5/NOPB
Texas Instruments
-
AZ431LANTR-G1
Diodes Incorporated
Tech Hub
A practical engineering guide to 3.3V and 5V logic compatibility, input thresholds, resistor dividers, translator ICs, MOSFET level shifting, I2C pull-ups, timing limits and power-sequencing risks.
The 74HC595 uses push-pull logic outputs, while the TPIC6B595 uses 50 V open-drain DMOS sinks for higher-power loads. This guide compares timing, current limits, 3.3 V interfacing, load wiring, thermal…
The 74HC595 converts serial data into eight stable parallel outputs. This guide covers pin functions, shift and storage timing, OE and MR behavior, drive-current limits, cascading, voltage compatibilit…
A technical comparison of level-sensitive latches and edge-triggered flip-flops, covering timing windows, setup and hold limits, master–slave operation, time borrowing, race-through, HDL inference and…
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
