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Analog Devices Inc./Maxim Integrated MAX6138BEXR33-T
- Part No.:
- MAX6138BEXR33-T
- Manufacturer:
- Analog Devices Inc./Maxim Integrated
- Category:
- Voltage Reference
- Package:
- SC-70, SOT-323
- Datasheet:
-
MAX6138BEXR33-T.pdf
- Description:
- VOLTAGE REFERENCE
- Quantity:
- Payment:
- Shipping:
Inventory:10,000
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Product details
Overview
MAX6138BEXR33-T from Maxim Integrated is a precision two-terminal shunt-mode bandgap voltage reference with a fixed reverse breakdown voltage of 3.3000 V, ±0.2% initial accuracy (Grade B), 25 ppm/°C max temperature coefficient, and operation over –40°C to +85°C. It delivers stable regulation across 67 µA to 15 mA shunt current in space-constrained portable systems requiring high-accuracy analog sensing or ADC/DAC biasing.
For engineers reviewing the MAX6138BEXR33-T datasheet, MAX6138BEXR33-T pinout, MAX6138BEXR33-T application, or MAX6138BEXR33-T equivalent, key selection criteria include its SC70-3 package footprint, no-output-capacitor stability, low 50 µVRMS wideband noise (10 Hz–10 kHz), and guaranteed dynamic impedance ≤0.8 Ω at 1 mA - critical for battery-powered instrumentation and precision data acquisition.
Technical Context
The MAX6138BEXR33-T implements a laser-trimmed BiCMOS bandgap core to achieve tight initial tolerance and low thermal drift. Its two-terminal architecture functions as a programmable current sink, maintaining 3.3000 V across terminals 1 (+) and 2 (–) when reverse-biased within 67 µA–15 mA.
Unlike series references, it requires no input capacitor and remains stable with any capacitive load. Pin 3 is unconnected (N.C.) or tied to pin 2, eliminating layout ambiguity and simplifying PCB routing in ultra-dense designs.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | 3.3000 V ±0.2% at +25°C - ensures accurate 3.3 V rail monitoring or ADC reference without calibration. |
| Initial Accuracy Grade | B-grade (±0.2%) - balances cost and performance for industrial-grade measurement systems. |
| Temp Coefficient | ≤25 ppm/°C over –40°C to +85°C - limits voltage drift to ±0.75 mV across full operating range. |
| Shunt Current Range | 67 µA to 15 mA - supports low-power sleep modes and high-current transient loads without dropout. |
| Dynamic Impedance | ≤0.8 Ω at 1 mA, 120 Hz - minimizes output perturbation during load transients in sensor front-ends. |
| Wideband Noise | 50 µVRMS (10 Hz–10 kHz) - preserves signal integrity in 16-bit+ data converters. |
| Long-Term Stability | 120 ppm after 1000 hours - enables reliable performance in unattended field-deployed equipment. |
Pinout & Package
MAX6138BEXR33-T uses the 3-pin SC70-3 surface-mount package (1.8 mm × 1.8 mm), 50% smaller than SOT23 alternatives. Pin 3 is No Connection (N.C.) and must be left floating or connected to pin 2 per datasheet guidance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 (+) | Anode / Positive terminal | Connects to regulated node; sinks current to maintain 3.3 V across pins 1–2. |
| 2 (–) | Cathode / Negative terminal | Reference ground return; forms shunt path with pin 1 under reverse bias. |
| 3 (N.C.) | No connection | Must remain unconnected or shorted to pin 2 - not used for biasing or feedback. |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-small SC70-3 footprint | 1.8 mm × 1.8 mm area - enables placement in <10 mm² PCB real estate for wearables and IoT nodes. |
| No external capacitor required | Stable with 0–∞ output capacitance - eliminates BOM line item and layout sensitivity to parasitic C. |
| Low dynamic impedance | ≤0.8 Ω at 1 mA - maintains regulation during fast load steps common in microcontroller wake-up events. |
| Laser-trimmed accuracy | ±0.2% over temperature - reduces system-level calibration burden in factory test flows. |
| Bandgap-based architecture | BiCMOS process with 70-transistor core - achieves predictable TC and long-term drift vs. Zener alternatives. |
Applications
| Portable Medical Sensors | Industrial Data Loggers |
|---|---|
|
Use Scenario: Battery-powered ECG front-end amplifying mV-level biopotentials with 16-bit SAR ADC sampling. IC Role / Device Role / Timing Role: Shunt voltage reference providing stable 3.3 V reference for ADC VREF and op-amp bias rails. Use Value: 50 µVRMS noise and ≤0.8 Ω dynamic impedance prevent SNR degradation and ensure <±1 LSB error across temperature. |
Use Scenario: Remote environmental monitor logging temperature/humidity via 24-bit sigma-delta ADC. IC Role / Device Role / Timing Role: Precision 3.3 V reference for ADC reference and sensor excitation circuitry. Use Value: ±0.2% initial accuracy and 25 ppm/°C TC enable single-point calibration valid over –40°C to +85°C field operation. |
| Smartphone Power Management | Automotive Cabin Sensors |
|
Use Scenario: Mobile SoC power rail monitoring using internal ADC with external precision reference. IC Role / Device Role / Timing Role: Low-quiescent shunt reference supplying 3.3 V to PMIC telemetry circuits. Use Value: 67 µA minimum operating current extends battery life in always-on monitoring mode without sacrificing accuracy. |
Use Scenario: Occupancy detection module with MEMS accelerometer and low-power MCU in vehicle cabin. IC Role / Device Role / Timing Role: Stable 3.3 V reference for accelerometer signal conditioning and ADC conversion. Use Value: SC70-3 size allows integration near sensor die; 120 ppm long-term stability ensures >10-year calibration validity. |
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 | 3.0 V fixed, ±0.5% initial accuracy, 100 ppm/°C TC, SOT-23-3 package | Lower accuracy and higher drift limit use in non-critical biasing only | Select when cost is primary constraint and 3.0 V output suffices |
| ADR3433ARJZ-R7 | 3.3 V, ±0.1% initial accuracy, 10 ppm/°C TC, SOT-23-5 (series topology) | Requires input capacitor and higher minimum supply headroom | Select for ultra-low drift where board space permits larger package and extra components |
Compared with TLVH431ACDBVR and ADR3433ARJZ-R7, the MAX6138BEXR33-T uniquely combines SC70-3 size, no-capacitor operation, and 0.2% accuracy - making it optimal for miniaturized, low-component-count systems where 3.3 V reference stability directly impacts measurement fidelity.
Availability
MAX6138BEXR33-T is available at Aetrix Electronics and suitable for portable medical sensors, industrial data loggers, and smartphone power management systems requiring stable component supply with consistent parametric performance across production lots.
Supply support for MAX6138BEXR33-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 and mixed-signal ICs for demanding industrial, automotive, and communications applications.
The MAX6138 family delivers high-accuracy, low-drift shunt references in ultra-compact SC70 packages - engineered specifically for space-constrained, battery-operated systems needing stable voltage references without external components.
FAQ
What is the maximum shunt current rating for MAX6138BEXR33-T?
The MAX6138BEXR33-T supports up to 15 mA shunt current while maintaining regulation and specified accuracy. Absolute maximum reverse current is 20 mA - exceeding this risks permanent damage. For continuous operation, design within 67 µA–15 mA per datasheet limits to ensure long-term stability and thermal safety.
Can MAX6138BEXR33-T be used with capacitive loads?
Yes, MAX6138BEXR33-T is explicitly designed to be stable with any output capacitance - including 0 µF. No external capacitor is required or recommended, simplifying layout and reducing BOM count. This behavior is verified across all operating currents and temperatures in the official datasheet.
What does the "B" in MAX6138BEXR33-T signify?
The "B" denotes Grade B initial accuracy: ±0.2% at +25°C. The full ordering code MAX6138BEXR33-T confirms 3.3000 V output, –40°C to +85°C temperature range, SC70-3 package, and B-grade tolerance - distinct from A-grade (±0.1%) or C-grade (±0.5%) variants.
Is pin 3 of MAX6138BEXR33-T functional or optional?
Pin 3 of MAX6138BEXR33-T is designated N.C. (No Connection) and is not functional. Per Maxim's datasheet, it must be left floating or connected to pin 2 (cathode); it must never be driven or used for feedback. This eliminates routing complexity and avoids unintended bias conditions.
How does MAX6138BEXR33-T compare to LM4040 in size and performance?
MAX6138BEXR33-T is 50% smaller than LM4040 in SOT-23 and offers superior specifications: ±0.2% vs. ±0.5% initial accuracy, 25 ppm/°C vs. 100 ppm/°C TC, and lower 50 µVRMS noise. It also operates down to 67 µA - enabling longer battery life in always-on applications where LM4040 requires higher quiescent current.
MAX6138BEXR33-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:
- ±0.2%
- 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
MAX6138BEXR33-T FAQ
1.How can I place an order for MAX6138BEXR33-T through Aetrix?
Please submit a Request for Quotation (RFQ) for MAX6138BEXR33-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 MAX6138BEXR33-T reliable?
The price and inventory of MAX6138BEXR33-T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MAX6138BEXR33-T is usually 5 days.
3.What payment methods are accepted for MAX6138BEXR33-T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MAX6138BEXR33-T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MAX6138BEXR33-T?
MAX6138BEXR33-T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MAX6138BEXR33-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 MAX6138BEXR33-T?
For technical support, including MAX6138BEXR33-T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MAX6138BEXR33-T requirements.
6.How does Aetrix verify that MAX6138BEXR33-T is sourced from the original manufacturer or authorized distributors?
All MAX6138BEXR33-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 MAX6138BEXR33-T meets industry standards.
7.What is the process for return or replacement of MAX6138BEXR33-T?
All MAX6138BEXR33-T units undergo pre-shipment inspection (PSI). If there is an issue with MAX6138BEXR33-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 MAX6138BEXR33-T part is unused and in its original packaging.
Return procedure for MAX6138BEXR33-T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MAX6138BEXR33-T Tags
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