My Inquiry
My Account
Analog Devices Inc. LT3744IUHE#TRPBF
- Part No.:
- LT3744IUHE#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- LED Drivers
- Package:
- 36-WFQFN Exposed Pad
- Datasheet:
-
LT3744IUHE#TRPBF.pdf
- Description:
- IC LED DRIVER CTRLR PWM 36QFN
- Quantity:
- Payment:
- Shipping:
Inventory:3,183
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT3744IUHE#TRPBF from Analog Devices (formerly Linear Technology) is a high-current synchronous step-down LED driver IC designed for precision current regulation in RGB LED systems and DLP projector illumination. It delivers up to 20A continuous or 40A pulsed LED current, supports 3.3V–36V input, achieves ±3% current regulation accuracy, and features three independent PWM/CTRL channels for multi-current-state control - enabling flicker-free color mixing in heads-up displays and laser projection.
For engineers reviewing the LT3744IUHE#TRPBF datasheet, LT3744IUHE#TRPBF pinout, LT3744IUHE#TRPBF application, or LT3744IUHE#TRPBF equivalent, key selection considerations include its unique inverting buck-boost topology with floating VEE, triple-channel analog/digital dimming (20:1 analog, 3000:1 PWM), integrated gate drivers (TG/BG), and thermally enhanced 5mm × 6mm QFN-36 package with exposed VEE pad for high-power thermal management.
Technical Context
The LT3744IUHE#TRPBF implements fixed-frequency peak current mode control with dual regulation loops: a primary LED current loop referenced to VEE (via LED_ISP/LED_ISN) and a secondary voltage regulation loop (FB pin, 1.205V threshold). Its architecture enables grounded heat sink operation for RGB LEDs by allowing VEE to float negative relative to SGND - critical for single-battery multicolor LED driving.
It integrates three independent PWM logic paths (PWM1/PWM2/PWM3) that select among CTRL1/CTRL2/CTRL3 reference voltages (0–1.5V), each controlling a dedicated PWM_OUTx driver for external NMOS FETs. The device also embeds synchronized gate drivers (TG/BG), internal 5V INTVCC regulator, and fault reporting via open-drain FAULT pin tied to SGND.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Max LED Current | 20A continuous / 40A pulsed - enables high-brightness RGB LED arrays without external current amplification. |
| Input Voltage Range | 3.3V to 36V - supports wide-input industrial and automotive LED power rails, including single Li-ion battery operation in inverting mode. |
| Current Regulation Accuracy | ±3% over full range - ensures consistent luminance across temperature and line/load variations in display and projection systems. |
| Dimming Ratio | 3000:1 PWM / 20:1 analog - provides flicker-free grayscale and color blending for DLP and HUD applications. |
| Switching Frequency | 100kHz to 1MHz (RT-programmable) - allows optimization of efficiency vs. EMI and inductor size for compact designs. |
| Package | 36-Lead 5mm × 6mm QFN with exposed VEE pad - delivers θJC = 3°C/W thermal resistance for sustained high-current operation. |
| Operating Temp | –40°C to +125°C junction - qualified for industrial and automotive ambient environments without derating. |
Pinout & Package
LT3744IUHE#TRPBF is housed in a thermally enhanced 36-lead plastic QFN (5mm × 6mm) with exposed VEE pad (Pin 37), which must be soldered to PCB for thermal and electrical integrity. All signals are referenced either to SGND (inputs) or VEE (outputs, drivers, sense amps).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| EN/UVLO (1) | Enable & UVLO input | Precision enable with 1.30V rising threshold; pulls down at <1.235V; full shutdown below 0.5V - ensures controlled start-up and brownout protection. |
| CTRL1/2/3 (2,4,5) | Analog current reference inputs | Set regulated LED current (0–1.5V → 0–60mV across sense resistor); support 20:1 analog dimming per channel - enables precise multi-current-state color calibration. |
| PWM1/2/3 (7,8,9) | Digital channel select inputs | Select CTRL1/CTRL2/CTRL3 and assert corresponding PWM_OUT1/2/3 - enables time-multiplexed RGB current control without external logic. |
| LED_ISP/LED_ISN (16,15) | LED current sense differential inputs | Reference LED current regulation to VEE; regulate voltage drop across external sense resistor (e.g., 6mΩ) - enables accurate sensing in floating or negative-output configurations. |
| TG/BG (29,32) | High-side/low-side gate drivers | Integrated NMOS drivers with RON = 3Ω/2.5Ω (pull-up) and 1.5Ω (pull-down); non-overlap timing <50ns - eliminates external gate driver ICs and reduces layout complexity. |
| PWM_OUT1/2/3 (27,25,23) | External dimming FET drivers | Drive gates of external NMOS FETs in series with LED cathodes; VFNEG referenced to –15V below VEE - supports active dimming in high-side or low-side configurations. |
| VEE (26,28,33,35,37) | Internal ground reference | Common reference for all drivers, sense amps, and outputs; may float up to –20V below SGND - enables inverting buck-boost topology with grounded heatsink. |
| FAULT (11) | Open-drain fault flag | Pulled low on FB <250mV (undervoltage) or >1.1V (overvoltage), or LED_ISP–LED_ISN <6mV - provides system-level fault signaling to microcontroller or supervisor IC. |
Key Features
| Feature | Design Value |
|---|---|
| Inverting buck-boost topology | Allows VEE to float negative relative to SGND, enabling grounded heatsink use for RGB LEDs driven from a single Li-ion battery - eliminates need for isolated supplies or complex topologies. |
| Triple independent current channels | Three CTRL/PWM pairs (CTRL1/PWM1, etc.) with dedicated PWM_OUTx drivers - supports simultaneous or time-multiplexed control of red/green/blue LEDs with independent current and dimming profiles. |
| Thermal derating via CTRLT | CTRLT pin accepts NTC-derived voltage to dynamically reduce regulated LED current as temperature rises - prevents thermal runaway in enclosed projector or HUD modules. |
| Integrated 5V INTVCC regulator | Provides regulated 5V (±5%) at up to 50mA from VIN - powers internal circuitry and BOOST capacitor charging, eliminating need for external LDO in most designs. |
| Open/short LED protection | Monitors FB voltage and LED_ISP–LED_ISN differential; asserts FAULT on open-circuit (FB >1.1V) or short (FB <250mV, sense voltage <6mV) - enhances system reliability in mission-critical lighting. |
Applications
| RGB LED Driver for DLP Projectors | Heads-Up Display (HUD) Illumination |
|---|---|
Use Scenario: Driving red/green/blue LED strings in a DLP-based pico-projector with sequential color field switching and high-speed PWM dimming. IC Role / Device Role / Timing Role: Primary LED current controller and PWM sequencer; regulates each color channel independently using CTRL1–3 and PWM1–3 to synchronize with DMD timing. Use Value: Enables 5000:1 flicker-free dimming and precise color point stability across temperature, critical for cinema-grade image fidelity. | Use Scenario: Illuminating combiner optics in automotive HUDs where space, thermal constraints, and EMI sensitivity limit component count. IC Role / Device Role / Timing Role: High-efficiency, thermally robust LED driver with integrated gate drivers and fault reporting - replaces discrete driver + controller + protection IC stack. Use Value: Reduces BOM count by ≥4 components and PCB area by >30%, while maintaining ±3% current accuracy under 125°C under-hood conditions. |
| High-Power Multicolor Stage Lighting | Industrial Machine Vision Lighting |
Use Scenario: Powering high-lumen RGBW LED modules in theatrical fixtures requiring smooth color transitions and strobe effects. IC Role / Device Role / Timing Role: Multi-channel constant-current source with programmable frequency and soft-start - manages inrush during rapid on/off cycling and avoids audible noise. Use Value: Delivers 40A pulsed current capability and 2000:1 analog dimming resolution, enabling cinematic dimming curves without PWM artifacts. | Use Scenario: Driving high-intensity, spectrally tuned LED arrays in automated optical inspection systems requiring stable, repeatable illumination. IC Role / Device Role / Timing Role: Precision current regulator with ±3% accuracy and open/short LED fault detection - ensures consistent exposure and eliminates false defect triggers from LED failure. Use Value: Guarantees <±0.5% luminance drift over 8-hour production runs, directly improving measurement repeatability in vision-guided robotics. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar high-current LED driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LTC3783EFE#PBF | Single-channel, no integrated PWM_OUT drivers; requires external MOSFETs for dimming; lower max current (15A). | Lacks triple-channel analog/PWM control and VEE-floating capability - unsuitable for RGB multiplexing or inverting buck-boost. | Choose only for simpler monochrome LED systems where cost is prioritized over integration and topology flexibility. |
| TPS92692QPWPRQ1 | Automotive-qualified; integrated 12-bit DAC for analog dimming; no VEE floating or inverting topology support. | Designed for automotive headlight modules; lacks PWM_OUTx drivers and multi-channel CTRL selection logic. | Prefer for AEC-Q100-compliant front-lighting; avoid for DLP/HUD where VEE isolation and fast channel switching are required. |
Compared with LTC3783EFE#PBF and TPS92692QPWPRQ1, the LT3744IUHE#TRPBF uniquely combines triple-channel current control, VEE-referenced floating operation, integrated PWM_OUT drivers, and 40A pulsed capability - making it the only option capable of replacing discrete solutions in high-end projection and HUD systems without compromising performance or board space.
Availability
LT3744IUHE#TRPBF is available at Aetrix Electronics and suitable for DLP projector illumination, automotive heads-up displays, high-power stage lighting, and industrial machine vision lighting requiring stable component supply, long-term lifecycle support, and guaranteed industrial temperature grade (–40°C to +125°C).
Supply support for LT3744IUHE#TRPBF 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
Analog Devices, Inc. (ADI) acquired Linear Technology in 2017 and maintains full product support, documentation, and manufacturing continuity for the LT3744 family.
The LT3744IUHE#TRPBF belongs to ADI's high-performance LED driver product line, engineered specifically for demanding projection, display, and high-brightness illumination applications requiring precision current regulation, multi-channel control, and thermally robust packaging.
FAQ
What is the maximum continuous LED current supported by the LT3744IUHE#TRPBF?
The LT3744IUHE#TRPBF supports up to 20A continuous LED current when properly heatsinked using the exposed VEE pad. Its pulsed current capability reaches 40A for short durations, enabled by peak current mode control and thermal derating via the CTRLT pin. This rating assumes operation within the –40°C to +125°C junction temperature range and adherence to recommended PCB layout guidelines for thermal dissipation.
How does the LT3744IUHE#TRPBF achieve grounded heatsink operation for RGB LEDs?
The LT3744IUHE#TRPBF achieves grounded heatsink operation by allowing its internal ground (VEE) to float negative relative to system ground (SGND) - up to –20V - while referencing all LED current sensing (LED_ISP/LED_ISN) and gate drivers (TG/BG) to VEE. This enables the LED anode/cathode to remain at system ground potential, permitting direct mechanical attachment of the heatsink to the PCB ground plane without isolation barriers.
Can the LT3744IUHE#TRPBF drive multiple LED strings simultaneously with independent current control?
Yes, the LT3744IUHE#TRPBF supports independent current control of up to three LED strings via its three dedicated analog control inputs (CTRL1/CTRL2/CTRL3) and corresponding digital select pins (PWM1/PWM2/PWM3). Each combination activates a specific current setpoint and asserts the matching PWM_OUTx driver, enabling time-multiplexed or concurrent RGB current regulation without external multiplexers or controllers.
What protection features are integrated into the LT3744IUHE#TRPBF?
The LT3744IUHE#TRPBF integrates open-LED detection (via FB >1.1V), shorted-LED detection (via FB <250mV and LED_ISP–LED_ISN <6mV), overvoltage protection (OVP), overcurrent protection (inductor OC threshold at 110mV), thermal shutdown, and fault reporting through the open-drain FAULT pin. These protections operate autonomously without microcontroller intervention, ensuring robust operation in unattended lighting systems.
Is the LT3744IUHE#TRPBF compatible with frequency synchronization from an external clock source?
Yes, the LT3744IUHE#TRPBF supports external frequency synchronization via the SYNC pin (Pin 10). When driven with a clean CMOS clock signal, the internal oscillator locks to the external frequency - provided the RT resistor is selected to set the free-running frequency ~10% slower than the SYNC signal. This feature enables EMI reduction through spread-spectrum alignment and synchronization across multiple converters in dense PCB layouts.
LT3744IUHE#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 36-WFQFN Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- DC DC Controller
- Topology:
- Step-Down (Buck)
- Internal Switch(s):
- No
- Number of Outputs:
- 3
- Voltage - Supply (Min):
- 3.3V
- Voltage - Supply (Max):
- 36V
- Voltage - Output:
- -
- Current - Output / Channel:
- -
- Frequency:
- 1MHz
- Dimming:
- Analog, PWM
- Applications:
- -
- Operating Temperature:
- -40°C ~ 125°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 36-QFN (5x6)
LT3744IUHE#TRPBF FAQ
1.How can I place an order for LT3744IUHE#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT3744IUHE#TRPBF 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 LT3744IUHE#TRPBF reliable?
The price and inventory of LT3744IUHE#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT3744IUHE#TRPBF is usually 5 days.
3.What payment methods are accepted for LT3744IUHE#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT3744IUHE#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT3744IUHE#TRPBF?
LT3744IUHE#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT3744IUHE#TRPBF 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 LT3744IUHE#TRPBF?
For technical support, including LT3744IUHE#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT3744IUHE#TRPBF requirements.
6.How does Aetrix verify that LT3744IUHE#TRPBF is sourced from the original manufacturer or authorized distributors?
All LT3744IUHE#TRPBF 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 LT3744IUHE#TRPBF meets industry standards.
7.What is the process for return or replacement of LT3744IUHE#TRPBF?
All LT3744IUHE#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LT3744IUHE#TRPBF, 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 LT3744IUHE#TRPBF part is unused and in its original packaging.
Return procedure for LT3744IUHE#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT3744IUHE#TRPBF 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 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…
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…
