My Inquiry
My Account
Diodes Incorporated AP431ARL-7
- Part No.:
- AP431ARL-7
- Manufacturer:
- Diodes Incorporated
- Category:
- Voltage Reference
- Package:
- TO-236-3, SC-59, SOT-23-3
- Datasheet:
-
AP431ARL-7.pdf
- Description:
- IC VREF SHUNT ADJ 0.5% SC59R
- Quantity:
- Payment:
- Shipping:
Inventory:2,246
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
AP431ARL-7 from Diodes Incorporated is a 3-terminal adjustable precision shunt regulator with 2.495V ±0.5% reference voltage, 0.2Ω dynamic output impedance, and 200mA sink current capability. It operates over –20°C to +85°C and supports programmable output voltages from 2.495V to 36V using two external resistors-commonly deployed in feedback loops of isolated DC-DC converters and voltage monitors.
For engineers reviewing the AP431ARL-7 datasheet, AP431ARL-7 pinout, AP431ARL-7 application, or AP431ARL-7 equivalent, key selection criteria include reference tolerance (±0.5%), cathode current regulation threshold (300μA), temperature coefficient (30ppm/°C), and SOT25 package compatibility with space-constrained power supply designs.
Technical Context
The AP431ARL-7 implements an internal bandgap reference and high-gain transconductance amplifier driving an NPN pass transistor, enabling sharp turn-on response and low-output-impedance regulation. Its active output circuitry replaces Zener diodes in precision feedback paths where stability and low drift are critical.
It functions as a 2.495V reference comparator with cathode-anode voltage control via external resistor divider; regulation initiates when cathode voltage exceeds VREF × (1 + R1/R2). The device maintains stable operation across 300μA–200mA cathode current range and exhibits <20mV reference deviation over full temperature range.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Reference Voltage | 2.495V ±0.5% - enables fixed or programmable output without trim potentiometers, reducing BOM cost and long-term drift. |
| Sink Current Capability | 200mA - supports direct regulation in medium-power SMPS feedback or current-sink applications up to 0.5W dissipation in SOT25. |
| Dynamic Output Impedance | 0.2Ω - ensures minimal output voltage variation under load transients, critical for tight-regulation feedback loops. |
| Min Cathode Current | 300μA - defines lowest operating point for reliable regulation; allows ultra-low-quiescent designs with high-value bias resistors. |
| Temp Coefficient | 30ppm/°C - guarantees ≤±8mV reference shift over –20°C to +85°C, suitable for industrial-grade power supplies. |
| Output Voltage Range | 2.495V to 36V - set by external R1/R2 divider; supports wide-range adaptability across AC/DC adapters and telecom PSUs. |
| Operating Temperature | –20°C to +85°C - validated extended commercial range for use in non-automotive embedded power systems. |
Pinout & Package
AP431ARL-7 is packaged in RoHS-compliant, lead-free SOT25 (SC-74A) with gull-wing leads and thermal pad-compatible footprint. This 5-pin package supports higher power dissipation (550mW) than SOT23 variants while maintaining PCB area efficiency.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1: CATHODE | Regulated output node | Connects to switched-node side of optocoupler or error amplifier; sinks current to maintain VREF at REF pin. |
| 2: ANODE | Current return path | Typically tied to system ground or low-side reference; completes regulation loop with cathode and REF. |
| 3: REF | Reference input | High-impedance (1.4–3.5μA typical) node sensing divided voltage; sets regulation threshold via R1/R2 network. |
| 4: ANODE | Redundant anode terminal | Internally connected to Pin 2; used for enhanced thermal conduction and lower parasitic inductance in high-frequency designs. |
| 5: NC | No connect | Unbonded die pad; must remain unconnected per datasheet to avoid parametric shift or latch-up risk. |
Key Features
| Feature | Design Value |
|---|---|
| Precision reference tolerance | ±0.5% (AP431A grade) eliminates need for post-production calibration or trimming in mid-tier power supplies. |
| Low dynamic output impedance | 0.2Ω enables <10mV load regulation error across 10–200mA cathode current range in flyback feedback networks. |
| Sharp turn-on response | Sub-microsecond rise time supports fast transient recovery in digitally controlled PSUs and adaptive voltage scaling circuits. |
| Programmable output voltage | Configurable from 2.495V to 36V using standard 1% resistors-reduces SKU count across multiple output-voltage platforms. |
| Lead-free & halogen-free | SOT25 package meets RoHS 2 and JEDEC J-STD-020 reflow profiles; compatible with lead-free assembly processes. |
Applications
| AC/DC Adapter Feedback | Isolated DC-DC Converter |
|---|---|
|
Use Scenario: Secondary-side voltage regulation in 5–24V wall adapters with optocoupler-based isolation. IC Role / Device Role / Timing Role: Shunt regulator providing precise reference to optocoupler LED, closing primary-side PWM loop via photocurrent feedback. Use Value: ±0.5% reference tolerance ensures ±1.5% output accuracy across line/load/temperature, meeting Level VI efficiency requirements. |
Use Scenario: Output voltage sensing in 48V-to-12V isolated buck-derived converters for industrial PLCs. IC Role / Device Role / Timing Role: Precision shunt element in secondary-side error amplifier circuit, setting regulated 12V output with fast transient response. Use Value: 0.2Ω output impedance minimizes voltage droop during 10A load steps, improving dynamic regulation to <±50mV. |
| Voltage Monitor Circuit | Constant-Current Sink |
|
Use Scenario: Dual-threshold overvoltage/undervoltage detection in battery management systems for 3S Li-ion packs. IC Role / Device Role / Timing Role: Comparator-like function using REF pin as high-impedance sense node; triggers crowbar or disable signal at preset thresholds. Use Value: 30ppm/°C tempco ensures <±15mV threshold drift over –20°C to +70°C, enabling reliable cell-level protection without calibration. |
Use Scenario: LED current control in signage drivers requiring stable 350mA output across input voltage variation. IC Role / Device Role / Timing Role: Shunt regulator configured as constant-current sink by fixing REF voltage and sensing cathode current through sense resistor. Use Value: 200mA sink rating and 300μA minimum cathode current allow accurate 350mA setting with <±2% error over temperature and line. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar adjustable shunt regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TL431ACDBVR | 2.5V ±0.5% reference, 100mA max sink, SO-8 package, higher 0.35Ω output impedance | Limited to lower-power applications; SO-8 footprint requires more PCB area than SOT25 | Select when legacy SO-8 layout reuse is required and power dissipation stays below 300mW. |
| KA431AZTA | 2.5V ±2.2% reference, 100mA sink, SC-59 package, 0.4Ω output impedance, wider temp range (–40°C to +105°C) | Lower precision and higher impedance reduce regulation accuracy in high-performance SMPS | Choose only for cost-sensitive, non-critical applications where ±2.2% tolerance and slower transient response are acceptable. |
Compared with TL431ACDBVR and KA431AZTA, AP431ARL-7 delivers tighter reference tolerance (±0.5%), lower output impedance (0.2Ω), and higher sink current (200mA) in a compact SOT25 package-making it optimal for space-constrained, high-accuracy isolated power supplies where thermal performance and regulation fidelity are prioritized.
Availability
AP431ARL-7 is available at Aetrix Electronics and suitable for AC/DC adapters, isolated DC-DC converters, and voltage monitor circuits requiring stable component supply, consistent parametric performance, and RoHS-compliant packaging.
Supply support for AP431ARL-7 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
Diodes Incorporated is a global semiconductor company specializing in discrete, analog, and mixed-signal solutions for power management, signal integrity, and connectivity applications.
AP431ARL-7 belongs to Diodes' precision shunt regulator product line, engineered for high-accuracy voltage reference and feedback control in cost-sensitive yet performance-demanding power conversion systems.
FAQ
What is the minimum cathode current required for regulation in AP431ARL-7?
The AP431ARL-7 requires a minimum cathode current of 300μA to maintain regulation, verified across –20°C to +85°C. This value is specified in the Electrical Characteristics table under IKA(MIN) and confirmed in Figure 1's cathode current vs. cathode voltage curves. Operating below this threshold risks loss of regulation and output voltage drift.
Can AP431ARL-7 replace a Zener diode directly in existing designs?
Yes-AP431ARL-7 can directly replace Zener diodes in shunt regulator configurations, provided the external resistor network is recalculated for its 2.495V reference and the cathode current remains within 300μA–200mA. Its active circuitry provides sharper knee characteristics and lower dynamic impedance than passive Zeners, improving regulation accuracy and transient response.
Does AP431ARL-7 support operation above 36V cathode voltage?
No-absolute maximum cathode voltage is +36V per the Absolute Maximum Ratings table. Exceeding this risks permanent damage. For >36V applications, external clamping (e.g., series Zener or TVS) is required before the cathode pin, or a higher-voltage regulator like AP432 should be selected.
How does the NC pin (Pin 5) in SOT25 affect PCB layout?
Pin 5 is internally unconnected and must remain floating-no trace, pad, or plane should contact it. Connecting it risks parametric shift or latch-up due to stray capacitance or leakage. The recommended pad layout (per AP02001) isolates Pin 5 with clearance ≥0.2mm from adjacent copper to ensure specification compliance.
AP431ARL-7 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Diodes Incorporated
- Package/Case:
- TO-236-3, SC-59, SOT-23-3
- Series:
- -
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Reference Type:
- Shunt
- Output Type:
- Adjustable
- Voltage - Output (Min/Fixed):
- 2.495V
- Voltage - Output (Max):
- 36 V
- Current - Output:
- 200 mA
- Tolerance:
- ±0.5%
- Temperature Coefficient:
- 30ppm/°C
- Noise - 0.1Hz to 10Hz:
- -
- Noise - 10Hz to 10kHz:
- -
- Voltage - Input:
- -
- Current - Supply:
- -
- Current - Cathode:
- 500 µA
- Operating Temperature:
- -20°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- SC-59R
AP431ARL-7 FAQ
1.How can I place an order for AP431ARL-7 through Aetrix?
Please submit a Request for Quotation (RFQ) for AP431ARL-7 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 AP431ARL-7 reliable?
The price and inventory of AP431ARL-7 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for AP431ARL-7 is usually 5 days.
3.What payment methods are accepted for AP431ARL-7?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for AP431ARL-7 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for AP431ARL-7?
AP431ARL-7 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your AP431ARL-7 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 AP431ARL-7?
For technical support, including AP431ARL-7 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your AP431ARL-7 requirements.
6.How does Aetrix verify that AP431ARL-7 is sourced from the original manufacturer or authorized distributors?
All AP431ARL-7 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 AP431ARL-7 meets industry standards.
7.What is the process for return or replacement of AP431ARL-7?
All AP431ARL-7 units undergo pre-shipment inspection (PSI). If there is an issue with AP431ARL-7, 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 AP431ARL-7 part is unused and in its original packaging.
Return procedure for AP431ARL-7:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
AP431ARL-7 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
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…
LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…
Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…
Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.
18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…
Hall effect sensor guide covering working principle, linear and digital sensors, Arduino circuits, current sensing, speed detection, automotive applications, A3144 examples, signal filtering and datash…
Product Change Notification guide for electronic components, covering PCN meaning, PCN vs PDN/EOL, common change types, risk levels, form-fit-function review, engineering validation, BOM control, LTB/L…
A practical guide to blend door actuators, covering HVAC function, symptoms, location, AC and heater issues, reset and calibration, replacement cost, electrical diagnosis, compatibility checks, and rep…
