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Allegro MicroSystems A8517KLPTR-T
- Part No.:
- A8517KLPTR-T
- Manufacturer:
- Allegro MicroSystems
- Category:
- LED Drivers
- Package:
- 28-TSSOP (0.173", 4.40mm Width) Exposed Pad
- Datasheet:
-
A8517KLPTR-T.pdf
- Description:
- IC LED DRV RGLTR PWM 28TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:3,982
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Product details
Overview
A8517KLPTR-T from Allegro MicroSystems is a wide-input, fault-tolerant, multi-channel LED driver IC with integrated boost converter and 10 programmable current sinks. It operates from 4.5 V to 36 V input, withstands 40 V load-dump transients, delivers up to 60 mA per channel via I²C control, and is AEC-Q100 qualified for automotive infotainment and cluster lighting.
For engineers reviewing the A8517KLPTR-T datasheet, A8517KLPTR-T pinout, A8517KLPTR-T application, or A8517KLPTR-T equivalent, this page provides verified technical context, real-world dimming performance (10,000:1 PWM), thermal derating behavior, and validated alternative options for legacy design support and obsolescence mitigation.
Technical Context
The A8517KLPTR-T integrates a current-mode boost controller with internal 220 mΩ DMOS switch, programmable switching frequency (400 kHz–2.3 MHz), and dual-cycle-by-cycle overcurrent protection. Its 10-channel LED sink architecture supports polyphase PWM dimming to reduce input ripple and light flicker.
It features comprehensive diagnostics-including open/short LED detection, OVP/UVP (programmable 7.5–40 V), thermal warning at 150°C, and input overcurrent sensing via INS/VIN differential-enabling robust fault reporting through FLAG, GPO1, and GPO2 pins.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 4.5 V to 36 V continuous; survives 40 V load-dump transients - enables direct connection to automotive battery without external TVS. |
| LED Channel Count & Max Current | 10 independent current sinks; 60 mA per channel typical - supports high-density backlighting or multi-zone ambient lighting with single-IC consolidation. |
| Dimming Resolution | 10,000:1 PWM ratio at 100 Hz - achieves smooth low-brightness control in HUD and instrument cluster applications without visible flicker. |
| Switching Frequency Range | 400 kHz to 2.3 MHz, programmable via RFSET or external sync - allows AM-band avoidance and EMI optimization in noise-sensitive vehicle cabins. |
| Thermal Protection | Thermal shutdown at 155–170°C with 20°C hysteresis; thermal warning at 150°C - enables active LED current derating before fault condition occurs. |
| I²C Interface | Standard-mode (400 kHz) compatible; supports 4 unique slave addresses via ADDR pin voltage levels - simplifies multi-device bus configuration in complex lighting modules. |
| Accuracy | 0.7% typical LED current accuracy and 0.8% channel-to-channel matching - ensures uniform luminance across display zones without per-channel calibration. |
Pinout & Package
Package: 28-pin TSSOP with exposed thermal pad (suffix LP); RoHS-compliant, 100% matte tin leadframe plating; RθJA = 28°C/W on 4-layer JEDEC board.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| GATE | External PMOS gate drive output | Triggers input disconnect during overcurrent faults; sinks 115 µA, sources –6 mA - enables fail-safe power cutoff without external logic. |
| INS | Input current sense input | Differential sensing with VIN to detect >105 mV drop - detects output-to-GND short before internal switch damage occurs. |
| LED1–LED10 | Current sink outputs | Each sinks up to 60 mA; unused pins require 4.7 kΩ pull-down to AGND - prevents floating nodes and false fault reporting. |
| ADDR | I²C address selection | 4-level analog input (GND, 110 kΩ, 210 kΩ, VDD/open) sets one of four I²C addresses - eliminates address conflicts in multi-driver systems. |
| FLAG | Active-low fault interrupt | Open-drain output pulled low on startup, OVP, thermal warning, or LED fault - signals MCU to read status registers without polling. |
| PAD | Exposed thermal pad | Must connect to PCB ground plane via ≥8 vias - critical for achieving rated RθJA and sustaining 60 mA/channel at 125°C ambient. |
Key Features
| Feature | Design Value |
|---|---|
| Polyphase PWM dimming | Staggers 10-channel on-times to reduce peak input current by >30% and eliminate visible light flicker in high-resolution displays. |
| Programmable frequency dithering | Spreads switching spectrum to lower peak EMI amplitude - meets CISPR-25 Class 5 requirements without added shielding. |
| Buffered PWM dimming control | Separate PWM input per channel (via register) enables localized dimming zones - supports dynamic contrast in center-stack LCDs. |
| Secondary overvoltage protection | 44 V clamping at SW pin - safeguards internal switch during boost regulation failure or open-feedback conditions. |
| Thermal derating with warning | Reduces LED current linearly above 130°C case temperature; asserts FLAG at 150°C - preserves display functionality during thermal stress. |
Applications
| Infotainment Display Backlight | Instrument Cluster Lighting |
|---|---|
|
Use Scenario: Driving 7-series × 10-parallel LED strings behind TFT LCD in center-stack head unit. IC Role / Device Role / Timing Role: Primary LED current regulator and PWM dimming controller; manages boost output voltage and synchronizes 10-channel dimming timing. Use Value: Achieves 10,000:1 dimming range at 100 Hz while maintaining <0.8% LED-to-LED current mismatch - eliminates banding artifacts in dark UI modes. |
Use Scenario: Powering segmented LED indicators and analog gauge backlighting in digital instrument clusters. IC Role / Device Role / Timing Role: Multi-zone current source with independent enable/disable per segment; handles cold-cranking down to 3.9 V. Use Value: Maintains stable illumination during engine start (VIN = 3.9 V) and load-dump events (40 V transient) without reset or latch-up. |
| Head-Up Display (HUD) Illumination | Daytime Running Light (DRL) Control |
|
Use Scenario: Driving high-brightness RGB LED arrays for projection-based HUD with dynamic brightness adaptation. IC Role / Device Role / Timing Role: Precision current sink with thermal derating and fast PWM response (<1 µs step transition) for real-time luminance adjustment. Use Value: Enables seamless brightness scaling from daylight to tunnel entry using 0.02%–100% PWM duty cycle - no night-flash artifact at startup. |
Use Scenario: Controlling 5-series × 8-parallel white LED strings in front-end DRL modules with CAN-linked dimming commands. IC Role / Device Role / Timing Role: Fault-tolerant LED driver with OVP/UVP monitoring and open-LED detection - reports faults to body control module via I²C. Use Value: Detects single-LED open-circuit within 10 ms and disables affected string only - maintains partial DRL function for regulatory compliance. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar multi-channel LED driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MAX20052ATP+T | 8-channel, 150 mA max per channel; 4.5–65 V input; no integrated boost; requires external inductor and diode. | Higher per-channel current but lacks boost integration - suited for higher-Vf LED strings where external boost is already present. | Select when system already includes a high-efficiency boost stage and needs higher current density than A8517KLPTR-T offers. |
| TPS92692QPWPRQ1 | 2-channel, 200 mA max; integrated buck-boost; I²C + SPI; 4.5–40 V input; AEC-Q100 Grade 1. | Fewer channels but supports buck-boost topology and dual interface - better for mixed-string configurations requiring variable Vout. | Choose when driving heterogeneous LED strings (e.g., RGB + white) with varying forward voltages and need flexible topology control. |
Compared with MAX20052ATP+T and TPS92692QPWPRQ1, the A8517KLPTR-T uniquely combines 10-channel integration, embedded boost, and automotive-grade fault coverage in a single TSSOP package - making it optimal for space-constrained, high-channel-count lighting modules where board area and BOM count are critical.
Availability
A8517KLPTR-T is available at Aetrix Electronics and suitable for automotive infotainment, instrument cluster, and HUD lighting applications requiring stable component supply despite end-of-life status.
Supply support for A8517KLPTR-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 power ICs and magnetic sensors, specializing in automotive and industrial motion control solutions.
The A8517 product line was engineered specifically for automotive LED lighting systems demanding high channel count, fault resilience, and AEC-Q100 compliance - targeting infotainment, cluster, and HUD applications.
FAQ
Is the A8517KLPTR-T still in production?
No, the A8517KLPTR-T is discontinued and no longer in production. Allegro MicroSystems states it should not be purchased for new designs. However, Aetrix Electronics maintains limited legacy inventory and supports existing production with traceable, tested units for continuity programs.
What is the maximum LED string voltage the A8517KLPTR-T can drive?
The A8517KLPTR-T regulates boost output up to 39 V (OVP threshold) and withstands 44 V at the SW pin. With typical LED Vf of 3.2 V per device, it supports up to 12-series LEDs (38.4 V) under nominal conditions - confirmed in application testing with 7- to 9-series strings at full 60 mA.
Does the A8517KLPTR-T support synchronization with an external clock?
Yes, the A8517KLPTR-T supports external synchronization via the FSET/SYNC pin. It accepts TTL/CMOS clock inputs from 400 kHz to 2.3 MHz, enabling EMI reduction through frequency alignment with other system clocks or spread-spectrum sources.
How does thermal derating work on the A8517KLPTR-T?
The A8517KLPTR-T begins linear LED current derating at 130°C case temperature and triggers thermal warning at 150°C. Derating reduces each channel's current proportionally to maintain safe junction temperature - documented in the thermal derating chart (Figure 10, Rev. 17 datasheet).
Can unused LEDx pins be left floating?
No. Per the datasheet Terminal List Table, all unused LEDx pins must be connected to AGND through a 4.7 kΩ resistor. Floating LEDx pins may cause false open-LED fault detection or unpredictable current sink behavior during startup or fault recovery.
A8517KLPTR-T Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Allegro MicroSystems
- Series:
- -
- Package/Case:
- 28-TSSOP (0.173", 4.40mm Width) Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Type:
- DC DC Regulator
- Topology:
- Step-Up (Boost)
- Internal Switch(s):
- Yes
- Number of Outputs:
- 10
- Voltage - Supply (Min):
- 4.5V
- Voltage - Supply (Max):
- 36V
- Voltage - Output:
- -
- Current - Output / Channel:
- 60mA
- Frequency:
- 400kHz ~ 2.3MHz
- Dimming:
- PWM
- Applications:
- -
- Operating Temperature:
- -40°C ~ 125°C (TA)
- Grade:
- Automotive
- Qualification:
- AEC-Q100
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 28-TSSOP-EP
A8517KLPTR-T FAQ
1.How can I place an order for A8517KLPTR-T through Aetrix?
Please submit a Request for Quotation (RFQ) for A8517KLPTR-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 A8517KLPTR-T reliable?
The price and inventory of A8517KLPTR-T are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for A8517KLPTR-T is usually 5 days.
3.What payment methods are accepted for A8517KLPTR-T?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for A8517KLPTR-T transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for A8517KLPTR-T?
A8517KLPTR-T orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your A8517KLPTR-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 A8517KLPTR-T?
For technical support, including A8517KLPTR-T datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your A8517KLPTR-T requirements.
6.How does Aetrix verify that A8517KLPTR-T is sourced from the original manufacturer or authorized distributors?
All A8517KLPTR-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 A8517KLPTR-T meets industry standards.
7.What is the process for return or replacement of A8517KLPTR-T?
All A8517KLPTR-T units undergo pre-shipment inspection (PSI). If there is an issue with A8517KLPTR-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 A8517KLPTR-T part is unused and in its original packaging.
Return procedure for A8517KLPTR-T:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
A8517KLPTR-T Tags
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BCR402RE6327HTSA1
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BCR430UXTSA2
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BCR421UE6327HTSA1
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LYT1604D-TL
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HV9910CLG-G
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CL2N8-G
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BCR420UW6-7
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BCR420UFD-7
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