A6217KLJTR-1-T - 1.5A 48V PWM Dimmable Buck LED Driver | Allegro
MPN： A6217KLJTR-1-T ✓ 啟用中A6217KLJTR-1-T 概覽
A buck LED driver is a switching converter that steps down a higher DC bus voltage to a lower, regulated LED forward voltage while actively maintaining average output current (rather than output voltage) as the controlled quantity. Constant-current regulation protects LED strings from thermal runaway, brightness drift, and catastrophic overcurrent when individual LED forward voltages vary with temperature. Buck regulators sit within the broader power management IC family used wherever DC LED strings must be driven from a higher-voltage supply such as 12 V, 24 V, or 48 V industrial/automotive buses.
Key differentiating features of the A6217KLJTR-1-T include AEC-Q100 automotive qualification, true average output current control (rather than peak current), 1.5 A continuous output over temperature (the A6217KLJTR-T variant delivers 3 A), and integrated cycle-by-cycle protection. The exposed thermal pad provides a low thermal resistance path, essential when dissipating (VIN - VLED) x ILED at high duty cycles in 24 V automotive body-electronics applications.
Architecturally, the A6217 uses a peak-current-mode control loop with an external sense resistor and an internal compensation network. The high-side integrated MOSFET simplifies PCB layout by eliminating external switching transistors, while the integrated low-side synchronous rectifier (when enabled) improves efficiency versus a simple diode-rectified buck. PWM dimming is implemented by modulating the EN/PWM pin, allowing high-contrast dimming down to very low duty cycles.
Typical end-system applications are automotive exterior lighting (DRLs, fog lamps, turn signals), interior ambient lighting, architectural and signage LED strips, industrial machine-vision illuminators, and emergency-vehicle strobe systems. The 48 V maximum input makes it suitable for trucks, buses, and industrial 48 V bus architectures.
When designing with this device, calculate worst-case power dissipation as (VIN_max - VLED) x ILED and verify junction temperature using the SOIC-EP thermal pad. Place the input bulk capacitor directly at the VIN pad and route the LED string return through the high-side sense resistor to the CS pin for accurate current sensing.
This page synthesizes distributor pricing, AEC-Q100 application guidance, and practical design notes not consolidated on the Allegro product page, giving automotive and industrial LED-driver engineers a single reference.
直接替換替代品，適用於 A6217KLJTR-1-T — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： A6217KLJTR-1-T （相同外形與佔位） — 差異在於 Package, Topology, Protection Features, Automotive Qualification, Number of Outputs.
A6217KLJTR-T
聯絡詢價
查看資料表 →A6217KLJTR-1-J
📋 參考替代品（不在目錄中）
A6217KEJTR-1-J
📋 參考替代品（不在目錄中）
A6217KEJTR-J
📋 參考替代品（不在目錄中）
A6217KLJTR-T-Q1
📋 參考替代品（不在目錄中）
A6217KLJTR-1-T 最大額定值與電氣特性
| 拓撲 | Step-Down (Buck) PWM Dimming |
| 供應電壓 | 6 V to 48 V |
| 最大輸出電流 | 1.5 A (continuous over operating temperature) |
| 輸出數量 | 1 |
| 輸出類型 | Constant-Current |
| Switching Topology | Buck with integrated MOSFET |
| 電流限制 | Cycle-by-cycle current limit |
| Dimming Control | PWM via EN/PWM logic input or power supply voltage |
| Supply Current (Quiescent) | 2500 uA |
| Automotive Qualification | AEC-Q100 qualified |
| 工作溫度 | -40C to +125C (automotive grade) |
| 封裝 | 8-SOIC-EP (Exposed Pad) |
| 安裝類型 | Surface Mount |
| MSL 等級 | 2 (per JEDEC J-STD-020) |
| RoHS 狀態 | Compliant |
| 致能腳位 | Yes (EN/PWM dual-function) |
| Thermal Pad | Yes (exposed pad for low thermal resistance) |
A6217KLJTR-1-T 腳位配置
| 腳位 1 | VIN — Input supply voltage (6 V to 48 V) |
| 腳位 2 | EN/PWM — Enable / PWM dimming logic input |
| 腳位 3 | CS — Current sense input (high-side sense resistor) |
| 腳位 4 | NC — Not connected (per datasheet) |
| 腳位 5 | GND — Ground return |
| 腳位 6 | SW — Switch node (to external inductor) |
| 腳位 7 | NC — Not connected (per datasheet) |
| 腳位 8 | NC — Not connected (per datasheet) |
| 腳位 EP | Exposed Pad — Thermal pad - connect to GND plane with thermal vias |
典型應用
A6217KLJTR-1-T 適用於 6 應用s: Automotive Daytime Running Lights (DRL), Automotive Fog Lamps and Turn Signals, Architectural and Signage LED Strip Lighting, Industrial Machine-Vision Illuminators, Emergency Vehicle LED Light Bars, Industrial 48V Bus LED Backlighting.
Automotive Daytime Running Lights (DRL)
The A6217KLJTR-1-T is well suited for automotive front DRL LED strings drawing up to 1.5 A. Its 6 V to 48 V input range covers 12 V passenger-car and 24 V commercial-vehicle electrical systems without additional pre-regulation, and AEC-Q100 qualification confirms reliability under hood and headlamp-module thermal stress. The integrated high-side MOSFET simplifies PCB layout, and true-average-current control keeps LED luminance constant across cold-crank transients (down to 6 V). PWM dimming via the EN/PWM pin allows synchronized DRL/position-lamp brightness modulation at any frequency up to the device's PWM dimming limit. Compared with discrete buck designs, the A6217KLJTR-1-T consolidates switching, current sense, and protection into a single 8-SOIC-EP footprint, reducing BOM count and PCB area in space-limited headlamp modules.
推薦
Automotive Fog Lamps and Turn Signals
Front fog lamps and amber turn signals require high-contrast PWM dimming at 1.5 A typical, which the A6217KLJTR-1-T supports via its EN/PWM dual-function pin. The device accepts a logic-level PWM signal directly or PWM modulation through the power supply rail, enabling body-control-module integration. Cycle-by-cycle current limit protects the LED string from wiring shorts, and the integrated thermal shutdown safeguards the exposed-pad package against fault-mode overtemperature. Automotive-grade -40C to +125C operation ensures reliable cold-start and under-hood thermal performance. The constant-average-current control eliminates LED-to-LED brightness mismatch that would otherwise occur with peak-current-mode regulation in thermally-stressed fog-lamp housings.
推薦
Architectural and Signage LED Strip Lighting
The A6217KLJTR-1-T drives 24 V architectural LED strips and illuminated signage at constant current up to 1.5 A. The 48 V maximum input accommodates 48 V industrial LED bus architectures used in high-bay commercial lighting and DMX-controlled facade installations. PWM dimming via the EN/PWM pin enables 0-10 V or DMX-to-PWM dimming interfaces for building-automation integration. AEC-Q100 qualification, while not mandatory for architectural use, provides assurance of long-term reliability and ESD robustness in outdoor enclosures. True-average current regulation maintains color consistency across long LED strip runs where forward-voltage variation would otherwise cause visible brightness gradients.
推薦
Industrial Machine-Vision Illuminators
Machine-vision ring lights and bar illuminators demand tight current regulation for uniform scene illumination and predictable camera exposure. The A6217KLJTR-1-T's true-average-current control maintains LED brightness within tight tolerances over the full -40C to +125C industrial operating range, eliminating the brightness drift that would otherwise require recalibration. The 6 V to 48 V input range supports both 24 V factory-floor PLC backplanes and 48 V industrial bus architectures. The integrated MOSFET switch keeps the PCB footprint compact for in-lens or in-bar illuminator housings, and cycle-by-cycle current limit protects LEDs from inrush transients during strobed exposures.
推薦
Emergency Vehicle LED Light Bars
Emergency-vehicle LED light bars demand AEC-Q100-grade reliability for vibration, temperature, and voltage-transient robustness. The A6217KLJTR-1-T's 1.5 A constant-current output per channel (multiple ICs can parallel-drive separate LED segments) combined with its PWM dimming capability enables synchronized strobe patterns at configurable frequencies. The 48 V maximum input protects against load-dump transients typical of 12 V and 24 V emergency-vehicle electrical systems. True-average current control ensures uniform warning-flash brightness across the light bar's full LED population, critical for first-responder visibility and regulatory compliance.
推薦
Industrial 48V Bus LED Backlighting
Industrial 48 V bus architectures increasingly power LED backlights for HMI panels, control-room displays, and machine-status indicators. The A6217KLJTR-1-T operates directly from 48 V without a pre-regulator, simplifying the power tree and improving end-to-end efficiency. Its 1.5 A constant-current output drives backlight LED strings up to approximately 36 V forward voltage (typical for high-luminance industrial backlights). The exposed thermal pad maintains low junction temperature even at 48 V input with full 1.5 A load, and PWM dimming via the EN/PWM pin allows brightness modulation synchronized with ambient-light sensors for power savings.
推薦
推薦產品摘要
工程參考資料，適用於 A6217KLJTR-1-T — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | A6217KLJTR-T | A6217KLJTR-1-J | A6217KLJTR-T-Q1 |
|---|---|---|---|---|
| Brand | Allegro MicroSystems | Allegro MicroSystems | Allegro MicroSystems | Allegro MicroSystems |
| Package | 8-SOIC-EP | 8-SOIC-EP (same) | 8-SOIC-EP (same) | 8-SOIC-EP (same) |
| Output Current | 1.5 A | 3 A | 1.5 A (same) | 3 A |
| Input Voltage Range | 6 V to 48 V | 6 V to 48 V (same) | 6 V to 48 V (same) | 6 V to 48 V (same) |
| Topology | Buck PWM dimming | Buck PWM dimming (same) | Buck PWM dimming (same) | Buck PWM dimming (same) |
| Automotive Grade | AEC-Q100 | AEC-Q100 | AEC-Q100 | AEC-Q100 (Q1 suffix) |
| Quiescent Current | 2500 uA | 2500 uA (same) | 2500 uA (same) | 2500 uA (same) |
| Reel Quantity | 3000 | 3000 | J suffix variant |
主要差異化特點
- 1.5 A continuous output over full -40C to +125C automotive temperature range (對比A6217KLJTR-T (3 A variant))
- True average output current control versus peak-current-only regulation (對比Generic buck LED drivers using peak-current mode)
- Integrated high-side MOSFET switch eliminates external switching transistor (對比Discrete buck LED drivers requiring external MOSFET)
設計說明
Estimated: At VIN=24V, VLED=12V (typical automotive LED string), and 1.5A load, power dissipation is approximately (24-12) x 1.5 = 18W. The 8-SOIC-EP exposed thermal pad MUST be soldered to a PCB copper plane of at least 1 square inch with thermal vias to the internal ground plane. Without proper PCB thermal design, junction temperature can exceed 150C at full automotive ambient (85C-105C), triggering thermal shutdown. For high-duty-cycle 48V bus applications, reduce VIN or LED current to keep dissipation below approximately 5W.
Place the input bulk capacitor (10 uF minimum, X7R ceramic or low-ESR electrolytic) directly at the VIN pin with the shortest possible trace. Route the LED return current through the high-side sense resistor to the CS pin with a Kelvin connection to avoid ground-loop errors in the current-sense path. The SW node traces must be kept short and wide to minimize EMI radiation. Place the exposed pad copper pour on top and inner layers with at least 4 thermal vias to the internal ground plane for proper heat spreading.
Do not operate the A6217KLJTR-1-T above 48V - load-dump events on 12V/24V automotive buses can exceed 60V transient. Add a TVS diode (such as SMBJ33A or SMBJ48A) at the input. The CS pin high-side sense resistor must be a low-inductance Kelvin-construction part; standard through-hole resistors will inject switching noise into the current-sense path and cause LED current ripple. The EN/PWM pin is a logic input - do not leave it floating; tie it high through a 100 kohm pull-up for always-on operation, or drive it directly from a 3.3V or 5V GPIO. When PWM dimming below 1 kHz, increase output capacitance to maintain LED current between pulses.
合規資訊
AEC-Q100 qualified per Allegro datasheet. RoHS compliant. The -T suffix indicates tape-and-reel delivery per JEDEC standards.
