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Analog Devices Inc./Maxim Integrated MAX6138CEXR33-T
- Part No.:
- MAX6138CEXR33-T
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Voltage Reference
- Package:
- SC-70, SOT-323
- Datasheet:
-
MAX6138CEXR33-T.pdf
- Description:
- VOLTAGE REFERENCE
- Quantity:
- Payment:
- Shipping:
Inventory:2,352
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Product details
Overview
MAX6138CEXR33-T from Maxim Integrated is a precision two-terminal shunt-mode bandgap voltage reference with a fixed 3.3000V reverse breakdown voltage, ±0.5% initial accuracy (Grade C), 25ppm/°C max temperature coefficient, and 45µA to 67µA minimum operating current - designed for high-stability analog sensing and ADC/DAC biasing in space-constrained portable systems.
For engineers reviewing the MAX6138CEXR33-T datasheet, MAX6138CEXR33-T pinout, MAX6138CEXR33-T application, or MAX6138CEXR33-T equivalent, key selection considerations include its SC70-3 package footprint, shunt-current regulation range (60µA–15mA), low 50µVRMS wideband noise (10Hz–10kHz), no-output-capacitor stability, and compatibility with capacitive loads up to 1µF.
Technical Context
The MAX6138CEXR33-T implements a laser-trimmed BiCMOS bandgap core delivering stable 3.3V reference voltage across -40°C to +85°C. Its two-terminal architecture requires only external series resistance for biasing, eliminating need for supply rails or enable logic.
It maintains regulation via dynamic shunt-current sinking (60µA–15mA), exhibits low 0.3–0.8Ω reverse dynamic impedance at 1mA, and achieves long-term stability of ≤120ppm over 1000 hours - all without external compensation components.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | 3.3000V ±0.5% at +25°C - ensures precise 3.3V system-level reference for 3.3V ADCs and regulators. |
| Initial Accuracy | ±0.5% (Grade C) - supports cost-sensitive industrial sensor front-ends where tight calibration is performed externally. |
| Temp Coefficient | ≤25ppm/°C - guarantees <±0.7mV drift over -40°C to +85°C, critical for battery-powered metering. |
| Shunt Current Range | 60µA to 15mA - enables operation from ultra-low-power sleep modes to full-load data acquisition. |
| Wideband Noise | 50µVRMS (10Hz–10kHz) - minimizes added noise in precision 12–16-bit SAR ADC reference paths. |
| Dynamic Impedance | 0.3–0.8Ω at 1mA - ensures minimal load-induced voltage shift during fast transient current demands. |
| Long-Term Stability | ≤120ppm (1000h) - reduces recalibration frequency in sealed industrial monitoring devices. |
Pinout & Package
MAX6138CEXR33-T is housed in a 3-pin SC70-3 surface-mount package (1.8mm × 1.8mm), 50% smaller than SOT23 equivalents. Pin 3 is No Connect (N.C.) and must be left floating or tied to Pin 2.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 (+) | Positive terminal (anode) | Connects to regulated output node; sinks shunt current when reverse-biased. |
| Pin 2 (-) | Negative terminal (cathode) | Reference ground return; forms 3.3V potential relative to Pin 1 under regulation. |
| Pin 3 (N.C.) | No connection | Must remain unconnected or shorted to Pin 2 - no internal function; avoids parasitic coupling. |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-small SC70-3 package | 1.8mm × 1.8mm footprint - enables placement in dense portable PCB layouts (e.g., wearables, IoT nodes). |
| No output capacitor required | Stable with 0–1µF capacitive loads - eliminates BOM cost and layout area for decoupling caps on reference node. |
| Low wideband noise | 50µVRMS (10Hz–10kHz) - directly improves effective resolution of 12-bit+ data converters sharing this reference. |
| Wide shunt-current range | 60µA–15mA operation - supports both microamp-level standby and milliamp-level active measurement cycles. |
| Laser-trimmed accuracy | Guaranteed ±0.5% initial tolerance - reduces post-manufacturing calibration burden in production test. |
Applications
| Portable Medical Sensors | Industrial Process Transmitters |
|---|---|
Use Scenario: Battery-powered handheld blood glucose meters requiring stable 3.3V reference for analog front-end signal conditioning. IC Role / Device Role / Timing Role: Two-terminal shunt reference providing precise 3.3V bias for op-amps and 16-bit SAR ADCs. Use Value: Enables <±0.5% measurement accuracy over full temperature range without external trimming or capacitor. |
Use Scenario: 4–20mA loop-powered pressure transmitters operating in harsh factory environments. IC Role / Device Role / Timing Role: Primary voltage reference for DAC-based current loop control and sensor excitation circuitry. Use Value: Maintains <±2.5mV output drift from -40°C to +85°C, ensuring compliance with IEC 61000-6-2 immunity requirements. |
| Smart Energy Meters | Automotive Cabin Sensors |
Use Scenario: DIN-rail mounted electricity meters needing long-term reference stability for revenue-grade kWh calculation. IC Role / Device Role / Timing Role: Shunt reference for metrology ADCs measuring voltage/current waveforms with >99.9% accuracy. Use Value: Delivers ≤120ppm drift over 1000h, reducing annual recalibration intervals and field maintenance costs. |
Use Scenario: Occupancy and air quality sensors inside automotive HVAC modules with limited board space. IC Role / Device Role / Timing Role: Compact 3.3V reference for MEMS sensor signal chains and microcontroller ADC inputs. Use Value: SC70-3 package fits within 2.0mm² footprint constraints while meeting AEC-Q200 temperature cycling requirements. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar shunt voltage reference applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TLVH431ACDBVR | 3.0V fixed output, ±0.5% initial accuracy, 100ppm/°C tempco, SOT-23-3 package | Lower precision and higher drift limit use in non-critical biasing; not suitable for 12-bit+ metrology | Select when 3.0V output and lower cost outweigh need for 3.3V matching and 25ppm/°C stability |
| LM4040C33IDCKR | 3.3V output, ±0.5% accuracy, 100ppm/°C tempco, SC70-3 package, 60µA–15mA range | Higher tempco increases drift by ~3.5× over -40°C to +85°C; identical pinout but inferior thermal performance | Choose only if legacy LM4040 design reuse is mandatory and thermal drift budget allows ≥2.5mV error |
Compared with TLVH431ACDBVR and LM4040C33IDCKR, MAX6138CEXR33-T delivers superior thermal stability (25ppm/°C vs. 100ppm/°C), tighter noise performance (50µVRMS vs. 80–120µVRMS), and guaranteed long-term drift - making it the preferred choice for high-accuracy, space-constrained 3.3V reference applications.
Availability
MAX6138CEXR33-T is available at Aetrix Electronics and suitable for portable medical sensors, industrial process transmitters, smart energy meters, and automotive cabin sensors requiring stable component supply across extended temperature ranges and multi-year production cycles.
Supply support for MAX6138CEXR33-T 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
Maxim Integrated (now part of Analog Devices) designs precision analog, mixed-signal, and power-management ICs for demanding industrial, medical, and communications applications.
The MAX6138 family delivers high-accuracy, low-noise shunt references in ultra-small SC70 packages - engineered specifically for battery-powered and space-constrained systems needing stable voltage references without external capacitors.
FAQ
What is the exact output voltage tolerance of MAX6138CEXR33-T at +25°C?
The MAX6138CEXR33-T has a nominal output voltage of 3.3000V with a Grade C initial accuracy of ±0.5%, meaning its measured reverse breakdown voltage falls between 3.2835V and 3.3165V at +25°C - confirmed in the Electrical Characteristics table for MAX6138_33 under TA = +25°C conditions.
Can MAX6138CEXR33-T operate without an external output capacitor?
Yes, MAX6138CEXR33-T is explicitly designed to be stable without any external output capacitor and remains stable with capacitive loads up to 1µF - a key differentiator from older shunt references like the LM4040, which require careful capacitor selection for phase margin.
What is the minimum shunt current required for regulation in MAX6138CEXR33-T?
The MAX6138CEXR33-T requires a minimum shunt current of 45µA (typical) to 67µA (max) to maintain regulation - specified as IRMIN in the Electrical Characteristics table for MAX6138_33, with 60µA being the guaranteed lower bound across temperature and grade.
Is MAX6138CEXR33-T compatible with capacitive loads in precision ADC reference circuits?
Yes, MAX6138CEXR33-T is stable with any output capacitance, including the 10nF–100nF bypass capacitors commonly used at ADC reference inputs - verified in Typical Operating Characteristics (Figure MAX6138 toc20–toc22) and explicitly stated in the Applications Information section.
How does the temperature coefficient of MAX6138CEXR33-T compare to LM4040C33IDCKR?
MAX6138CEXR33-T has a maximum temperature coefficient of 25ppm/°C, while LM4040C33IDCKR is rated at 100ppm/°C - meaning the MAX6138CEXR33-T exhibits up to 4× less voltage drift over the same temperature range, directly improving measurement repeatability in thermally varying environments.
MAX6138CEXR33-T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Package/Case:
- SC-70, SOT-323
- Series:
- -
- Packaging:
- Bulk
- Product Status:
- Obsolete
- Reference Type:
- Shunt
- Output Type:
- Fixed
- Voltage - Output (Min/Fixed):
- 3.3V
- Voltage - Output (Max):
- -
- Current - Output:
- 15 mA
- Tolerance:
- ±0.5%
- Temperature Coefficient:
- 25ppm/°C
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- 50µVrms
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 67 µA
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SC-70-3
MAX6138CEXR33-T FAQ
1.How can I place an order for MAX6138CEXR33-T through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX6138CEXR33-T 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 MAX6138CEXR33-T reliable?
The price and inventory of MAX6138CEXR33-T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX6138CEXR33-T is usually 5 days.
3.What payment methods are accepted for MAX6138CEXR33-T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX6138CEXR33-T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX6138CEXR33-T?
MAX6138CEXR33-T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX6138CEXR33-T 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 MAX6138CEXR33-T?
For technical support, including MAX6138CEXR33-T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX6138CEXR33-T requirements.
6.How does Aetrix verify that MAX6138CEXR33-T is sourced from the original manufacturer or authorized distributors?
All MAX6138CEXR33-T 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 MAX6138CEXR33-T meets industry standards.
7.What is the process for return or replacement of MAX6138CEXR33-T?
All MAX6138CEXR33-T units undergo pre-shipment inspection (PSI). If there is an issue with MAX6138CEXR33-T, 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 MAX6138CEXR33-T part is unused and in its original packaging.
Return procedure for MAX6138CEXR33-T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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