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Allegro MicroSystems A6275ELWTR-T
- Part No.:
- A6275ELWTR-T
- Manufacturer:
- Allegro MicroSystems
- Category:
- LED Drivers
- Package:
- 16-SOIC (0.295", 7.50mm Width)
- Datasheet:
-
A6275ELWTR-T.pdf
- Description:
- IC LED DRVR LINEAR 75.5MA 16SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:2,574
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Product details
Overview
A6275ELWTR-T from Allegro MicroSystems is an 8-bit serial-input constant-current latched LED driver with eight NPN sink outputs, 90 mA max per channel, undervoltage lockout, and CMOS-compatible 20 MHz serial data input-designed for multiplexed LED displays in industrial panel meters and signage systems.
For engineers reviewing the A6275ELWTR-T datasheet, A6275ELWTR-T pinout, A6275ELWTR-T application, or A6275ELWTR-T equivalent, this page delivers verified electrical specs, SOICW-16 package details, latch/enable timing behavior, output current regulation via REXT, and direct substitution guidance versus A6279 and TB62705CP.
Technical Context
The A6275ELWTR-T integrates a 8-bit CMOS shift register, parallel latches, and eight matched NPN constant-current sink drivers-all on a single BiCMOS die. It operates with 4.5–5.5 V logic supply and supports cascade via CMOS serial data output (SDO).
Output current is set externally via REXT (e.g., 250 Ω → 75.5 mA typ), with ±6.0% matching between outputs at VCE = 0.7 V. Undervoltage lockout activates below 3.4–4.0 V to prevent erratic operation during power ramp-up.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Type | Eight NPN constant-current sink drivers, each rated 90 mA continuous at 85°C |
| Logic Supply | 4.5–5.5 V; enables direct interface with 5 V microcontrollers without level shifting |
| Serial Data Rate | Up to 20 MHz typical; supports high-speed LED refresh in dynamic display applications |
| Current Setting | Externally adjustable via single REXT; 40.0 mA typ at 470 Ω, 75.5 mA typ at 250 Ω |
| UVLO Threshold | 3.4–4.0 V; disables outputs until stable VDD is established |
| Propagation Delay | 300–1000 ns (CLOCK→OUT, LATCH→OUT, ENABLE→OUT); ensures deterministic timing in synchronized displays |
| Package | 16-pin SOICW (LW), Pb-free, 100% matte tin leadframe plating |
Pinout & Package
16-pin SOICW (LW) package, 10.30 mm × 7.50 mm × 2.65 mm body, gull-wing leads, JEDEC MS-013 AA compliant. Thermal resistance RθJA = 48 °C/W on 4-layer PCB.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | GND | Common reference for logic and output stages; must be low-impedance to avoid latch misfires |
| 2 | SERIAL DATA IN | CMOS input accepting serial bitstream; data sampled on rising clock edge |
| 3 | CLOCK | Rising-edge-triggered shift register clock; min pulse width 50 ns |
| 4 | LATCH ENABLE | High-level strobe transfers shift register contents to output latches; min pulse width 100 ns |
| 5–12 | OUT0–OUT7 | Constant-current NPN sinks; each drives one LED cathode with user-set current via REXT |
| 13 | OUTPUT ENABLE | Active-low blanking control; high = all outputs disabled (inter-digit blanking) |
| 14 | SERIAL DATA OUT | CMOS output for daisy-chaining multiple A6275 devices; fanout ≥10 |
| 15 | REXT | Analog input node connecting external resistor to set all eight output currents simultaneously |
| 16 | VDD | 5 V logic supply; powers shift register, latches, and internal bias circuits |
Key Features
| Feature | Design Value |
|---|---|
| 90 mA constant-current sink per channel | Enables direct drive of high-brightness LEDs without external current-limiting resistors per segment |
| Undervoltage lockout (UVLO) | Prevents partial or unstable operation during brown-out conditions; ensures clean startup/reset |
| 20 MHz serial data input rate | Supports >1 kHz full-display refresh in 8-digit multiplexed systems with minimal MCU overhead |
| CMOS serial data output (SDO) | Allows seamless expansion to 16-, 24-, or 32-bit LED arrays using single MCU SPI line |
| Pin-compatible with TB62705CP | Permits drop-in replacement in existing designs using that Toshiba driver, preserving PCB layout |
Applications
| Industrial Panel Meters | LED Signage Modules |
|---|---|
|
Use Scenario: Driving 7-segment or dot-matrix LED digits in factory-floor instrumentation with ambient temperatures up to 85°C. IC Role / Device Role / Timing Role: Constant-current sink driver providing precise brightness control across all segments while synchronizing with MCU SPI updates. Use Value: Eliminates per-segment current resistors, reduces BOM count by 8×, and maintains uniform LED intensity despite VF variation across batches. |
Use Scenario: Controlling red/green/blue LED modules in outdoor advertising signs requiring inter-digit blanking for flicker-free scanning. IC Role / Device Role / Timing Role: Serial-to-parallel latched driver enabling simultaneous update of all 8 outputs with zero ghosting during digit transitions. Use Value: Active-low OUTPUT ENABLE allows precise blanking between digit scans, suppressing visual artifacts in high-brightness environments. |
| Test & Measurement Equipment | Automotive Dashboard Displays |
|
Use Scenario: Driving multi-digit LED readouts in benchtop multimeters and oscilloscope front panels where EMI immunity and thermal stability are critical. IC Role / Device Role / Timing Role: BiCMOS-based driver delivering low logic-power dissipation (<1.4 mA standby) and robust noise rejection on shared ground planes. Use Value: Copper leadframe and low thermal resistance (48 °C/W) sustain full 90 mA output current continuously at 85°C ambient-no derating required. |
Use Scenario: Illuminating segmented warning indicators (e.g., oil pressure, battery, ABS) in vehicle instrument clusters operating over –40°C to +85°C. IC Role / Device Role / Timing Role: Automotive-grade LED driver with UVLO ensuring reliable startup during cold cranking (VBAT dip to 3.8 V). Use Value: Guaranteed operation across full automotive temperature range with no external thermal management needed for typical indicator loads. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar constant-current LED driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| A6279 | Successor device with open-LED detection, dot correction, and extended 150 mA output capability; same SOICW-16 footprint | Required for new designs needing fault diagnostics or higher-current LEDs; not pin-compatible due to added diagnostic pins | Select A6279 for new designs requiring enhanced reliability features; A6275ELWTR-T remains valid for legacy repair or cost-sensitive volume production. |
| TB62705CP | Pin-compatible Toshiba part with identical 8-bit serial interface and 100 mA sink rating; different internal UVLO threshold (3.0 V) | Drop-in replacement in existing PCB layouts; requires validation of lower UVLO point in low-voltage systems | Use TB62705CP only when board layout reuse is mandatory and system VDD transient behavior confirms compatibility with 3.0 V UVLO. |
Compared with A6279, the A6275ELWTR-T lacks open-LED reporting but offers proven stability in mature designs; versus TB62705CP, it provides tighter current matching (±6.0% vs ±10%) and higher UVLO margin-critical for industrial power supplies with slow ramp-up.
Availability
A6275ELWTR-T is available at Aetrix Electronics and suitable for industrial panel meters, LED signage modules, and test equipment requiring stable component supply despite its Last Time Buy status.
Supply support for A6275ELWTR-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
Allegro MicroSystems is a U.S.-based designer of high-performance magnetic sensors and precision power ICs, founded in 1989 and headquartered in Worcester, Massachusetts.
The A6275 product line targets LED display systems requiring accurate, thermally stable constant-current drive with minimal MCU resource usage-optimized for industrial and commercial signage applications.
FAQ
What is the maximum continuous output current per channel for the A6275ELWTR-T?
The A6275ELWTR-T supports up to 90 mA constant-current sink per output (OUT0–OUT7) continuously across the full operating temperature range of –40°C to +85°C, provided thermal limits are observed. This rating assumes proper PCB copper area and 48 °C/W junction-to-ambient thermal resistance in the SOICW package.
How is output current set on the A6275ELWTR-T?
Output current on the A6275ELWTR-T is set by a single external resistor (REXT) connected between pin 15 (REXT) and ground. For example, a 250 Ω resistor yields 75.5 mA typical per channel at VCE = 0.7 V; a 470 Ω resistor yields 40.0 mA typical. Current matching across channels remains within ±6.0%.
Is the A6275ELWTR-T still in active production?
No-the A6275ELWTR-T is classified as Last Time Buy (LTB) with last order deadline April 30, 2011. It remains available for existing customer applications but is not recommended for new designs. A6279 is Allegro's designated successor with enhanced features including open-LED detection.
Does the A6275ELWTR-T support daisy-chaining with other LED drivers?
Yes-the A6275ELWTR-T includes a CMOS serial data output (pin 14, SDO) that permits cascade connection of multiple devices. The SDO signal is compatible with the SERIAL DATA IN (pin 2) of the next A6275ELWTR-T, enabling expansion beyond 8 outputs using a single SPI data line from the host controller.
What is the purpose of the OUTPUT ENABLE pin on the A6275ELWTR-T?
The OUTPUT ENABLE pin (pin 13) is an active-low control that blanks all eight outputs simultaneously. When driven high, all OUT0–OUT7 are disabled-enabling inter-digit blanking in multiplexed LED displays to eliminate crosstalk and ghosting. This function operates independently of latch state and does not affect internal register contents.
A6275ELWTR-T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Allegro MicroSystems
- Series:
- -
- Package/Case:
- 16-SOIC (0.295", 7.50mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- Linear
- Topology:
- Shift Register
- Internal Switch(s):
- Yes
- Number of Outputs:
- 8
- Voltage - Supply (Min):
- 4.5V
- Voltage - Supply (Max):
- 5.5V
- Voltage - Output:
- 4V
- Current - Output / Channel:
- 75.5mA
- Frequency:
- 20MHz
- Dimming:
- -
- Applications:
- -
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-SOIC
A6275ELWTR-T FAQ
1.How can I place an order for A6275ELWTR-T through Aetrix?
Please submit a Request for Quotation (RFQ) for A6275ELWTR-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 A6275ELWTR-T reliable?
The price and inventory of A6275ELWTR-T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for A6275ELWTR-T is usually 5 days.
3.What payment methods are accepted for A6275ELWTR-T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for A6275ELWTR-T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for A6275ELWTR-T?
A6275ELWTR-T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your A6275ELWTR-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 A6275ELWTR-T?
For technical support, including A6275ELWTR-T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your A6275ELWTR-T requirements.
6.How does Aetrix verify that A6275ELWTR-T is sourced from the original manufacturer or authorized distributors?
All A6275ELWTR-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 A6275ELWTR-T meets industry standards.
7.What is the process for return or replacement of A6275ELWTR-T?
All A6275ELWTR-T units undergo pre-shipment inspection (PSI). If there is an issue with A6275ELWTR-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 A6275ELWTR-T part is unused and in its original packaging.
Return procedure for A6275ELWTR-T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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