My Inquiry
My Account
Allegro MicroSystems A6276ELW-T
- Part No.:
- A6276ELW-T
- Manufacturer:
- Allegro MicroSystems
- Category:
- LED Drivers
- Package:
- 24-SOIC (0.295", 7.50mm Width)
- Datasheet:
-
A6276ELW-T.pdf
- Description:
- IC LED DRVR LINEAR 75.5MA 24SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:4,356
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
A6276ELW-T from Allegro MicroSystems is a 16-bit serial-input, constant-current latched LED driver in 24-pin SOICW package, featuring 16 NPN sink drivers with user-adjustable current (up to 90 mA per output via REXT), 20 MHz serial data input rate at 5 V logic supply, and active-low OUTPUT ENABLE for inter-digit blanking - used in multiplexed LED signage and industrial panel displays.
For engineers reviewing the A6276ELW-T datasheet, A6276ELW-T pinout, A6276ELW-T application, or A6276ELW-T equivalent, this device serves as a high-current, latch-enabled serial-to-parallel LED driver with undervoltage lockout, CMOS serial data output for cascading, and thermal-aware power dissipation characteristics across –40°C to +85°C ambient.
Technical Context
The A6276ELW-T integrates a 16-bit CMOS shift register, parallel latches, and 16 matched NPN constant-current sink drivers - all controlled by CLOCK, LATCH ENABLE, and active-low OUTPUT ENABLE signals. Its serial interface supports daisy-chaining via CMOS SERIAL DATA OUT, enabling expansion beyond 16 outputs without additional microcontroller I/O.
Output current is set globally by a single external resistor (REXT) connected to pin 23, delivering 34–87 mA per channel depending on REXT value and VCE; matching accuracy is ±1.5% typical. Undervoltage lockout activates below 3.4 V VDD, preventing erratic operation during power ramp-up.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Configuration | 16-channel NPN constant-current sink drivers, each capable of 90 mA continuous at TA ≤ 85°C with proper thermal design |
| Serial Data Rate | Up to 20 MHz at VDD = 5 V - enables fast refresh in high-resolution LED matrices |
| Current Setting | Externally programmable via single REXT resistor (e.g., 470 Ω → 40 mA typ., 250 Ω → 75.5 mA typ.) |
| Logic Supply | 4.5–5.5 V operation with undervoltage lockout at 3.4–4.0 V - ensures stable initialization |
| Timing Control | Separate LATCH ENABLE (high-active) and OUTPUT ENABLE (low-active) pins - decouples data loading from display enable |
| Thermal Resistance | RθJA = 85°C/W (SOICW, 1-layer JEDEC PCB) - requires thermal derating above 50°C ambient for full 90 mA per channel |
| Operating Temperature | –40°C to +85°C ambient - qualified for industrial-grade LED display systems |
Pinout & Package
24-pin SOICW (Small Outline Integrated Circuit, Wide-body) package with gull-wing leads, 1.27 mm pitch, 15.40 mm × 7.50 mm body size, and exposed pad not present (unlike LP variant). RoHS-compliant, 100% matte tin leadframe plating.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 | GND | Common reference for logic and power ground - must be low-impedance to avoid latch misfires due to switching noise |
| 2 | SERIAL DATA IN | CMOS-level serial data input synchronized to rising edge of CLOCK - accepts up to 20 MHz data stream |
| 3 | CLOCK | Rising-edge-triggered shift clock - minimum pulse width 50 ns, max transition time 10 μs |
| 4 | LATCH ENABLE | High-active signal that transfers shift register contents to output latches - enables synchronous update of all 16 outputs |
| 5–20 | OUT0–OUT15 | 16 NPN open-collector sink outputs - each delivers constant current set by REXT; voltage drop ≤ 0.75 V at 90 mA |
| 21 | OUTPUT ENABLE | Active-low global blanking control - disables all outputs simultaneously without affecting latch state |
| 22 | SERIAL DATA OUT | CMOS-level serial output for cascading - allows daisy-chaining multiple A6276 devices without external logic |
| 23 | REXT | Reference terminal for external current-setting resistor - sets identical sink current for all 16 outputs |
| 24 | SUPPLY (VDD) | 5 V nominal logic supply - powers shift register, latches, and internal bias; supports 4.5–5.5 V range |
Key Features
| Feature | Design Value |
|---|---|
| 16-bit constant-current sink outputs | Each output delivers tightly matched current (±1.5% typical) set by one external resistor - simplifies BOM and eliminates per-channel trimming |
| High-speed serial interface | 20 MHz max data rate at 5 V - supports >1 kHz refresh in 16×16 LED matrices with minimal microcontroller overhead |
| Inter-digit blanking support | Active-low OUTPUT ENABLE pin allows precise timing control of digit visibility - essential for flicker-free multiplexed displays |
| Undervoltage lockout (UVLO) | Lockout threshold 3.4–4.0 V - prevents partial register updates and output glitches during brown-out conditions |
| Cascadable serial output | CMOS SERIAL DATA OUT drives next device's SERIAL DATA IN - enables arbitrary-width LED arrays using single SPI bus |
Applications
| LED Signage Panels | Industrial HMI Displays |
|---|---|
Use Scenario: Outdoor alphanumeric LED signs with 8–16 digit segments, refreshed at ≥200 Hz to eliminate visible flicker. IC Role / Device Role / Timing Role: Constant-current sink driver for common-anode LED digits; handles serial data loading, latching, and blanking under microcontroller SPI control. Use Value: Delivers stable 75 mA per segment at 0.7 V drop, enabling bright red/green LEDs while maintaining <1.2 W total package dissipation at 25°C ambient. |
Use Scenario: Factory-floor operator panels with 4–8 seven-segment displays and status indicators, operating continuously at 60°C ambient. IC Role / Device Role / Timing Role: Latched LED driver providing galvanically isolated digit control via optocoupled SPI lines and local OUTPUT ENABLE blanking. Use Value: UVLO prevents erroneous digit activation during power cycling; RθJA = 85°C/W allows full 90 mA per output with 2-layer PCB copper pour and thermal vias. |
| Test Equipment Front Panels | Transportation Annunciators |
Use Scenario: Benchtop multimeters and oscilloscopes with dual 6-digit LED displays updated every 100 ms for measurement readouts. IC Role / Device Role / Timing Role: Serial-to-parallel converter driving multiplexed 7-segment digits; uses LATCH ENABLE to freeze displayed values during measurement acquisition. Use Value: 350 ns typical propagation delay (CLOCK→OUT) ensures sub-microsecond digit settling - critical for glitch-free numeric updates. |
Use Scenario: Bus/train destination signs with 12-character scrolling text, requiring high-current white LEDs (3.5 VF) driven at 25% duty cycle. IC Role / Device Role / Timing Role: High-side switched LED driver (with external PNP/MOSFET) paired with A6276ELW-T sink outputs for segment control. Use Value: Adjustable REXT allows precise 40 mA current per white LED segment at 0.7 VCE, minimizing heat rise in confined enclosures. |
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 |
|---|---|---|---|
| TB62706BF | Pin-compatible 16-bit sink driver; lacks undervoltage lockout and has lower max current (60 mA vs. 90 mA) | Requires external UVLO circuitry; limited to lower-brightness displays or forced-air-cooled designs | Select when legacy footprint compatibility is mandatory and 60 mA per channel suffices |
| A6275ELWTR-T | 8-bit version of same family; identical SOICW package, REXT interface, and timing specs but half the channel count | Used where board space permits two devices or where 8-output granularity matches display architecture | Choose for cost-sensitive 8-digit applications or when modular scalability is preferred over single-chip density |
Compared with TB62706BF, A6276ELW-T adds UVLO and +50% output current headroom; versus A6275ELWTR-T, it doubles channel count in same footprint - making it optimal for space-constrained, high-brightness LED signage requiring single-device integration.
Availability
A6276ELW-T is available at Aetrix Electronics and suitable for LED signage panels, industrial HMI displays, test equipment front panels, and transportation annunciators requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for A6276ELW-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 and manufacturer of high-performance magnetic sensors, motor drivers, and precision power ICs, headquartered in Worcester, Massachusetts.
The A6276 product line delivers robust, thermally optimized LED drivers for industrial and commercial signage - engineered for reliability in continuous-duty, high-current, multiplexed display applications.
FAQ
What is the maximum continuous output current per channel for A6276ELW-T at 85°C ambient?
The A6276ELW-T supports up to 90 mA per output continuously at TA = 85°C when mounted on a 1-layer JEDEC-standard PCB, provided the package thermal resistance (RθJA = 85°C/W) and actual power dissipation remain within limits. Derating is required above 50°C ambient for full 90 mA operation - consult Figure GP-062-9 in the datasheet for duty-cycle-dependent current limits.
How does the REXT resistor set output current in A6276ELW-T?
In the A6276ELW-T, the external resistor connected between pin 23 (REXT) and ground establishes a reference current that scales all 16 output currents proportionally. For example, a 470 Ω resistor yields ~40 mA per output at VCE = 0.7 V, while 250 Ω gives ~75.5 mA typ. Matching between outputs remains within ±1.5% typical regardless of REXT value.
Can A6276ELW-T be cascaded with other A6276 devices?
Yes, the A6276ELW-T supports seamless cascading via its CMOS SERIAL DATA OUT (pin 22), which connects directly to the SERIAL DATA IN (pin 2) of the next A6276 device. This allows building LED arrays of arbitrary width - e.g., three A6276ELW-T devices drive 48 segments using only one SPI bus and three dedicated control lines (CLOCK, LATCH ENABLE, OUTPUT ENABLE).
What is the function of the OUTPUT ENABLE pin on A6276ELW-T?
The OUTPUT ENABLE pin (pin 21) is an active-low global blanking control for the A6276ELW-T. When high, it disables all 16 output drivers (setting them to high-impedance off-state) without altering the data stored in the latches. This enables precise inter-digit blanking in multiplexed displays - critical for eliminating crosstalk and achieving uniform brightness across digits.
Does A6276ELW-T include undervoltage lockout, and what is its threshold?
Yes, the A6276ELW-T incorporates undervoltage lockout (UVLO) to prevent erratic behavior during power-up or brown-out. The UVLO threshold is specified as 3.4 V (min) to 4.0 V (max) - meaning the device holds all outputs inactive until VDD rises above ~3.7 V typical, then releases control once stable operation is confirmed.
A6276ELW-T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Allegro MicroSystems
- Series:
- -
- Package/Case:
- 24-SOIC (0.295", 7.50mm Width)
- Packaging:
- Tube
- Product Status:
- Obsolete
- Type:
- Linear
- Topology:
- Shift Register
- Internal Switch(s):
- Yes
- Number of Outputs:
- 16
- 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:
- 24-SOIC
A6276ELW-T FAQ
1.How can I place an order for A6276ELW-T through Aetrix?
Please submit a Request for Quotation (RFQ) for A6276ELW-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 A6276ELW-T reliable?
The price and inventory of A6276ELW-T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for A6276ELW-T is usually 5 days.
3.What payment methods are accepted for A6276ELW-T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for A6276ELW-T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for A6276ELW-T?
A6276ELW-T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your A6276ELW-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 A6276ELW-T?
For technical support, including A6276ELW-T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your A6276ELW-T requirements.
6.How does Aetrix verify that A6276ELW-T is sourced from the original manufacturer or authorized distributors?
All A6276ELW-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 A6276ELW-T meets industry standards.
7.What is the process for return or replacement of A6276ELW-T?
All A6276ELW-T units undergo pre-shipment inspection (PSI). If there is an issue with A6276ELW-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 A6276ELW-T part is unused and in its original packaging.
Return procedure for A6276ELW-T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
A6276ELW-T Tags
-
BCR402RE6327HTSA1
Infineon Technologies
-
BCR430UXTSA2
Infineon Technologies
-
BCR420UE6433HTMA1
Infineon Technologies
-
BCR420UE6327HTSA1
Infineon Technologies
-
BCR421UE6327HTSA1
Infineon Technologies
-
LYT1604D-TL
Power Integrations
-
HV9910CLG-G
Microchip Technology
-
CL2N8-G
Microchip Technology
-
BCR420UW6-7
Diodes Incorporated
-
BCR421UW6-7
Diodes Incorporated
-
BCR420UFD-7
Diodes Incorporated
-
BCR421UFD-7
Diodes Incorporated
Tech Hub
A practical engineering and sourcing framework covering lifecycle verification, lifetime-buy calculations, replacement qualification, supplier checks and counterfeit-risk controls.
TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.
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…
