My Inquiry
My Account
Analog Devices Inc. LT3922EUFD-1#TRPBF
- Part No.:
- LT3922EUFD-1#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- LED Drivers
- Package:
- 28-WFQFN Exposed Pad
- Datasheet:
-
LT3922EUFD-1#TRPBF.pdf
- Description:
- IC LED DRVR CTRLR PWM 2.3A 28QFN
- Quantity:
- Payment:
- Shipping:
Inventory:2,076
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT3922EUFD-1#TRPBF from Analog Devices is a monolithic synchronous step-up LED driver IC with integrated 2.3A/40V power switches, ±2.5% LED current regulation via external sense resistor, 25,000:1 PWM dimming capability at 100Hz, and Silent Switcher® architecture for low EMI. It operates from 2.8V to 36V input and supports up to 34V LED string voltage in boost, buck, or buck-boost configurations.
For engineers reviewing the LT3922EUFD-1#TRPBF datasheet, LT3922EUFD-1#TRPBF pinout, LT3922EUFD-1#TRPBF application, or LT3922EUFD-1#TRPBF equivalent, key selection criteria include its AEC-Q100 qualification for automotive lighting, programmable 200kHz–2MHz switching frequency with spread spectrum, internal PWM generator (7.3–129Hz), and dual control modes (analog voltage or duty-cycle input at CTRL pin).
Technical Context
The LT3922EUFD-1#TRPBF implements fixed-frequency peak current mode control with independent current and voltage regulation loops. Its current loop uses a transconductance amplifier (gm = 140µA/V) comparing ISP/ISN differential voltage against CTRL-derived reference, while the voltage loop (gm = 1000µA/V) overrides current regulation when FB exceeds 1.200V to prevent LED overvoltage.
It integrates a high-side PMOS gate driver (PWMTG) for external PWM dimming, an internal PWM signal generator (RP-pin programmable), and fault protection including open-circuit (FB > 1.140V + low ISP–ISN) and short-circuit detection (ISP–ISN > 150mV). Thermal shutdown and EN/UVLO (1.33V threshold) ensure robust operation across –40°C to 125°C junction temperature.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 2.8V to 36V - supports wide-range industrial and automotive battery inputs including cold-crank (6.5V) and load-dump (36V) conditions. |
| LED Current Regulation Accuracy | ±2.5% - ensures consistent brightness across temperature and line variations without calibration. |
| Switching Frequency Range | 200kHz to 2MHz - selectable via RT resistor or external SYNC clock; enables EMI optimization and compact magnetics. |
| PWM Dimming Ratio | 25,000:1 at 100Hz - achieves ultra-fine brightness control for machine vision and automotive adaptive lighting. |
| Internal Power Switches | 2.3A peak, 40V rating, 140mΩ bottom / 155mΩ top RDS(on) - eliminates need for external MOSFETs in ≤333mA LED string applications. |
| Operating Junction Temperature | –40°C to 125°C - qualified per AEC-Q100 Grade E, suitable for under-hood automotive lighting modules. |
| Package | 28-lead (4mm × 5mm) QFN with exposed thermal pad - provides θJA = 25°C/W on demo board DC2247A for efficient thermal management. |
Pinout & Package
LT3922EUFD-1#TRPBF is housed in a thermally enhanced 28-lead (4mm × 5mm) plastic QFN package with exposed GND pad (Pin 29) requiring soldering to PCB for thermal and electrical integrity. Pin count and layout match UFD package designation per Analog Devices ordering information.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| SW (Pins 1, 2, 24, 25) | Switch Node | Internally connected to both power switches; must be tied together and routed with low-inductance layout to minimize EMI and voltage spikes. |
| BST (Pin 3) | Bootstrap Supply | Drives top switch gate via 33nF BST–SW capacitor; internal diode charges capacitor during SW low phase. |
| ISP / ISN (Pins 10, 11) | Current Sense Inputs | Differential pair measuring voltage across external sense resistor; Kelvin connection required for ±2.5% regulation accuracy. |
| CTRL (Pin 8) | LED Current Programming | Accepts analog voltage (0.25–1.25V) or digital pulse (12.5–62.5% duty) to set regulated LED current; <200mV disables output. |
| PWM / RP (Pins 19, 18) | PWM Control Interface | PWM pin accepts external dimming signal or sets internal PWM duty (1–2V); RP pin sets internal PWM frequency (7.3–129Hz) with resistor to GND. |
| FAULT (Pin 14) | Open/Short LED Fault Indicator | Open-drain output pulled low on open-circuit (FB > 1.14V + ISP–ISN < 10mV) or short-circuit (ISP–ISN > 150mV). |
| EN/UVLO (Pin 5) | Enable & Undervoltage Lockout | 1.33V rising threshold with 25mV hysteresis; ties directly to VIN or resistor divider for battery undervoltage cutoff. |
Key Features
| Feature | Design Value |
|---|---|
| Silent Switcher® Architecture | Reduces EMI radiation by >30dB via integrated magnetic field cancellation, eliminating need for metal shielding in automotive EMC-compliant designs. |
| 25,000:1 PWM Dimming at 100Hz | Enables flicker-free, high-contrast illumination for machine vision inspection systems requiring precise intensity gradation. |
| Integrated 2.3A Synchronous Switches | Supports up to 333mA LED string current without external MOSFETs, reducing BOM count and PCB area in space-constrained lighting modules. |
| AEC-Q100 Qualified (Grade E) | Validated for automotive ambient temperatures (–40°C to +125°C), vibration, and lifetime reliability-enabling direct use in headlamp and DRL applications. |
| Programmable Spread Spectrum | Frequency dithering (100–125% of base fSW) via SYNC/SPRD pin reduces peak EMI by spreading energy across bandwidth, easing CISPR 25 Class 5 compliance. |
| Comprehensive Fault Protection | Detects open-circuit, short-circuit, overvoltage (FB OVLO), and thermal overload with configurable hiccup/latch-off response via SS pin resistor. |
Applications
| Automotive Adaptive Front Lighting | Industrial Machine Vision Illumination |
|---|---|
Use Scenario: High-brightness LED arrays in vehicle headlamps requiring dynamic beam shaping and glare-free zone control. IC Role / Device Role / Timing Role: Primary LED current regulator and PWM dimming controller managing multiple LED strings with synchronized 100Hz dimming. Use Value: ±2.5% current regulation maintains consistent lumen output across battery voltage swings (9–16V), while AEC-Q100 qualification ensures reliability in under-hood environments. |
Use Scenario: High-speed camera strobes in automated optical inspection (AOI) systems demanding microsecond-level LED turn-on precision. IC Role / Device Role / Timing Role: Constant-current source with rapid PWM recovery enabling sub-millisecond LED pulses for motion-blur-free imaging. Use Value: 25,000:1 dimming range allows pixel-level brightness calibration across multi-camera setups without mechanical ND filters. |
| Commercial LED Signage | Medical Endoscopic Light Sources |
Use Scenario: Outdoor RGB LED billboards exposed to wide temperature variation and long operational cycles. IC Role / Device Role / Timing Role: Boost converter driving series-connected LEDs with integrated overvoltage and open-LED protection. Use Value: 34V max LED string voltage supports 10+ white LEDs in series; thermal shutdown prevents luminance drift during sustained high-brightness operation. |
Use Scenario: Compact, low-EMI light engines for flexible endoscopes where electromagnetic interference could disrupt image sensor signals. IC Role / Device Role / Timing Role: Low-noise LED driver with Silent Switcher architecture minimizing conducted/radiated emissions near sensitive CMOS sensors. Use Value: Spread spectrum modulation and optimized layout reduce EMI peaks below CISPR 11 limits, avoiding costly shielding or filtering in medical-grade enclosures. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LED driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LT3922IUFD-1#TRPBF | Same silicon, rated for –40°C to 125°C but not AEC-Q100 qualified; identical electrical specs and pinout. | Not approved for automotive safety-critical lighting; suitable for industrial or commercial lighting where qualification isn't mandated. | Select when AEC-Q100 is unnecessary and cost sensitivity favors non-automotive grade. |
| LT3922HUFD-1#TRPBF | Same silicon, extended junction temperature range (–40°C to 150°C), AEC-Q100 qualified for higher-temperature under-hood locations. | Required for engine bay applications exceeding 125°C ambient; higher thermal derating margin than LT3922EUFD-1#TRPBF. | Select when operating junction temperature may exceed 125°C, e.g., near turbochargers or exhaust manifolds. |
Compared with LT3922IUFD-1#TRPBF, the LT3922EUFD-1#TRPBF adds formal AEC-Q100 qualification for automotive use, while LT3922HUFD-1#TRPBF extends thermal capability to 150°C-making the EUFD variant the optimal balance of automotive compliance and thermal margin for most front-end lighting modules.
Availability
LT3922EUFD-1#TRPBF is available at Aetrix Electronics and suitable for automotive lighting, machine vision systems, and industrial signage requiring stable component supply, AEC-Q100 compliance, and high-precision LED current regulation.
Supply support for LT3922EUFD-1#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. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, automotive, communications, and healthcare markets.
The LT3922EUFD-1#TRPBF belongs to Analog Devices' Silent Switcher LED driver product line, engineered specifically for low-EMI, high-reliability automotive and industrial lighting applications requiring precise current control and ultra-deep PWM dimming.
FAQ
What is the maximum LED string voltage supported by the LT3922EUFD-1#TRPBF?
The LT3922EUFD-1#TRPBF supports up to 34V LED string voltage, verified in the Absolute Maximum Ratings table and confirmed in Typical Application schematics where VOUT reaches 30V–36V depending on LED count. This enables driving 10–12 white LEDs in series at typical forward voltages (3.0–3.4V each) without external components.
Does the LT3922EUFD-1#TRPBF require external MOSFETs for PWM dimming?
No-the LT3922EUFD-1#TRPBF integrates a dedicated high-side PMOS gate driver (PWMTG pin) capable of directly driving external PMOS devices for PWM dimming. The IC itself does not include the PMOS switch, but the driver stage eliminates need for additional level-shifting or buffer circuitry when using discrete PMOS FETs like Si2319CDS.
How is the 25,000:1 PWM dimming ratio achieved in the LT3922EUFD-1#TRPBF?
The LT3922EUFD-1#TRPBF achieves 25,000:1 PWM dimming by accepting external 100Hz pulses at the PWM pin with precise timing control and fast current-loop recovery (<200ns propagation delay from PWM to PWMTG). This enables minimum on-times down to ~40ns, allowing full dimming range without visible flicker or current droop between pulses.
What thermal performance can be expected from the LT3922EUFD-1#TRPBF in a standard PCB layout?
On the DC2247A demo board, the LT3922EUFD-1#TRPBF achieves θJA = 25°C/W and θJC = 3.4°C/W. With proper thermal pad soldering and 2-in² copper pour, case temperature rise remains under 25°C at 333mA LED current and 2MHz switching-validated in Typical Performance Characteristic Figure G38.
Can the LT3922EUFD-1#TRPBF operate in buck mode, and what are the requirements?
Yes-the LT3922EUFD-1#TRPBF supports buck, boost, and buck-boost topologies per the Applications section. In buck mode, VIN must exceed VOUT, the SW node connects to input, and VOUT supplies the LED string. External diode and inductor placement must follow the buck configuration shown in Analog Devices' application notes to maintain stability and regulation accuracy.
LT3922EUFD-1#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 28-WFQFN Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- DC DC Controller
- Topology:
- Step-Up (Boost)
- Internal Switch(s):
- No
- Number of Outputs:
- 1
- Voltage - Supply (Min):
- 2.8V
- Voltage - Supply (Max):
- 36V
- Voltage - Output:
- -
- Current - Output / Channel:
- 2.3A
- Frequency:
- 200kHz ~ 2MHz
- Dimming:
- Analog, PWM
- Applications:
- Lighting
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- Automotive
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 28-QFN (4x5)
LT3922EUFD-1#TRPBF FAQ
1.How can I place an order for LT3922EUFD-1#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT3922EUFD-1#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 LT3922EUFD-1#TRPBF reliable?
The price and inventory of LT3922EUFD-1#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT3922EUFD-1#TRPBF is usually 5 days.
3.What payment methods are accepted for LT3922EUFD-1#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT3922EUFD-1#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT3922EUFD-1#TRPBF?
LT3922EUFD-1#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT3922EUFD-1#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 LT3922EUFD-1#TRPBF?
For technical support, including LT3922EUFD-1#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT3922EUFD-1#TRPBF requirements.
6.How does Aetrix verify that LT3922EUFD-1#TRPBF is sourced from the original manufacturer or authorized distributors?
All LT3922EUFD-1#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 LT3922EUFD-1#TRPBF meets industry standards.
7.What is the process for return or replacement of LT3922EUFD-1#TRPBF?
All LT3922EUFD-1#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LT3922EUFD-1#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 LT3922EUFD-1#TRPBF part is unused and in its original packaging.
Return procedure for LT3922EUFD-1#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT3922EUFD-1#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…
