My Inquiry
My Account
Analog Devices Inc. LT3932IUFD#PBF
- Part No.:
- LT3932IUFD#PBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- LED Drivers
- Package:
- 28-WFQFN Exposed Pad
- Datasheet:
-
LT3932IUFD#PBF.pdf
- Description:
- IC LED DRIVER RGLTR PWM 2A 28QFN
- Quantity:
- Payment:
- Shipping:
Inventory:118
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT3932IUFD#PBF from Analog Devices is a 36V, 2A synchronous step-down LED driver with Silent Switcher® architecture for low EMI, fixed-frequency peak-current control, and dual-mode dimming (analog voltage or PWM duty cycle at CTRL pin). It regulates LED current to ±1.5% accuracy, supports 0V–36V LED string voltage, and is qualified for automotive lighting applications.
For engineers reviewing the LT3932IUFD#PBF datasheet, LT3932IUFD#PBF pinout, LT3932IUFD#PBF application, or LT3932IUFD#PBF equivalent, key selection criteria include input voltage range (3.6V–36V), programmable switching frequency (200kHz–2MHz), internal PWM dimming capability (128:1 ratio), open/short LED fault reporting, and thermally enhanced 28-pin QFN package with exposed GND pad.
Technical Context
The LT3932IUFD#PBF integrates a synchronous buck controller with dual power switches, peak-current mode regulation, and independent current/voltage error amplifiers (gm = 200 µA/V and 480 µA/V). Its oscillator supports RT-resistor programming or external SYNC clock input, and spread-spectrum modulation reduces EMI by varying frequency between 100%–125% of nominal.
It features an analog-to-digital detector for CTRL pin signal interpretation, internal PWM generator (7.8 kHz typical with RP = 28.7 kΩ), high-side PMOS gate driver (PWMTG), and fault logic that pulls FAULT low for open-circuit (>950 mV FB) or short-circuit (<200 mV FB) conditions - all operating across –40°C to +125°C junction temperature.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 3.6V to 36V - supports wide automotive battery and industrial supply rails without pre-regulation. |
| Max LED Current | 2A - delivers sufficient drive for multi-LED strings in headlamps or machine vision illumination. |
| Current Regulation Accuracy | ±1.5% - ensures consistent luminance across temperature and unit-to-unit variation. |
| Switching Frequency Range | 200kHz to 2MHz - enables optimization of efficiency vs. size using small inductors and ceramic capacitors. |
| Dimming Ratio (PWM) | 5000:1 at 100Hz - achieves deep, flicker-free dimming for precision lighting control. |
| Package | 28-pin (4mm × 5mm) QFN with exposed thermal pad - provides low θJA (25°C/W) for high-power LED driver thermal management. |
| Operating Temp Range | –40°C to +125°C - meets AEC-Q100 Grade I requirements for under-hood automotive use. |
Pinout & Package
LT3932IUFD#PBF uses a thermally enhanced 28-pin plastic QFN (4mm × 5mm) with exposed GND pad (Pin 29), requiring soldering to PCB for thermal and electrical integrity. Absolute max ratings include VIN/EN/UVLO ≤ 40V and ISP/ISN ≤ 40V.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VIN (Pins 1, 4, 5, 14, 15) | Input Power Supply | Supplies analog circuitry and inductor current during top-switch conduction; requires local 2.2µF bypass to GND. |
| ISP / ISN (Pins 6, 7) | Current Sense Inputs | Differential inputs to sense voltage across external sense resistor; common-mode range 0V–36V supports high-side sensing. |
| CTRL (Pin 16) | LED Current Programming | Accepts analog voltage (250mV–1.25V) or digital pulse (100kHz–1MHz) to set regulated LED current with 20:1 control range. |
| PWM / RP / PWMTG (Pins 22, 9, 12) | Dimming Control Interface | PWM pin accepts external signal or sets internal PWM duty ratio; RP sets internal PWM frequency; PWMTG drives external high-side PMOS gate. |
| FB (Pin 4) | Output Voltage Limit Feedback | Monitors LED string voltage via resistor divider; triggers overvoltage lockout at 1.05V and fault reporting at <200mV or >950mV. |
| FAULT (Pin 8) | Open/Short Fault Indicator | Open-drain output pulled low during LED open-circuit or short-circuit conditions; requires 100kΩ pull-up to INTVCC. |
Key Features
| Feature | Design Value |
|---|---|
| Silent Switcher® Architecture | Minimizes EMI/EMC emissions via symmetrical layout and integrated return paths - eliminates need for external EMI filters in automotive designs. |
| Internal PWM Dimming Generator | Provides 128:1 dimming ratio without external timing components when RP resistor is used - simplifies system-level PWM generation. |
| Accurate LED Current Monitor (ISMON) | Delivers buffered 10mV/mV output proportional to ISP–ISN voltage - enables real-time current diagnostics and closed-loop feedback. |
| Programmable UVLO with Hysteresis | EN/UVLO threshold = 1.15V (±60mV), hysteresis = 20mV - ensures clean startup/shutdown and prevents brownout oscillation in noisy automotive environments. |
| Thermal Shutdown Protection | Activates above +150°C junction temperature - safeguards device during overload or poor heatsinking without latch-off unless configured via SS pin. |
Applications
| Automotive Headlamps | Industrial Machine Vision Lighting |
|---|---|
Use Scenario: High-intensity, dynamically adjustable forward lighting in ADAS-equipped vehicles requiring precise beam shaping and adaptive dimming. IC Role / Device Role / Timing Role: Primary LED current regulator and PWM dimming controller for multi-string matrix LED headlamps. Use Value: ±1.5% current regulation and 5000:1 PWM dimming enable pixel-level brightness control while meeting stringent automotive EMI limits via Silent Switcher®. | Use Scenario: High-stability, strobed illumination for high-speed camera inspection systems in factory automation. IC Role / Device Role / Timing Role: Synchronous buck LED driver with fast transient response and accurate current sourcing for pulsed illumination. Use Value: 200kHz–2MHz programmable frequency allows synchronization with camera frame rates; internal PWM generator eliminates external timing ICs. |
| Commercial Street Lighting | Architectural LED Signage |
Use Scenario: Outdoor LED luminaires operating from 12–48V DC microgrids or solar-charged batteries with wide ambient temperature swings. IC Role / Device Role / Timing Role: Robust, thermally efficient LED driver supporting long-life operation in unventilated enclosures. Use Value: –40°C to +125°C rating and 28-pin QFN with exposed pad ensure reliability in sealed outdoor housings; 36V max input accommodates 24V/48V systems. | Use Scenario: Color-consistent RGBW LED panels where individual channel current matching is critical for white point stability. IC Role / Device Role / Timing Role: Precision current source with analog control interface for per-channel dimming calibration. Use Value: 20:1 analog control range and ±1.2% output voltage regulation maintain tight color binning across channels without software compensation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LED driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LTC3783EFE#PBF | Non-synchronous boost/buck-boost topology; no integrated PWM dimming generator; lower max current (1.5A). | Requires external MOSFETs and dimming controller; suited for higher-output-voltage or bidirectional LED configurations. | Select when output voltage exceeds input or when boost capability is required - not drop-in for LT3932IUFD#PBF's synchronous buck + integrated dimming function. |
| TPS92692QPWPRQ1 | Automotive-grade buck LED driver with integrated N-channel high-side driver; supports up to 3A; lacks spread-spectrum EMI reduction. | Designed for direct high-side switch control without external PMOS; includes diagnostic registers via I²C interface. | Choose for systems needing digital diagnostics and higher current, but expect higher radiated emissions without external filtering. |
Compared with LTC3783EFE#PBF and TPS92692QPWPRQ1, the LT3932IUFD#PBF uniquely combines Silent Switcher® EMI performance, internal PWM dimming, and ±1.5% LED current accuracy in a single 28-pin QFN - making it optimal for space-constrained, high-reliability automotive and industrial LED systems where analog simplicity and low emissions are prioritized.
Availability
LT3932IUFD#PBF is available at Aetrix Electronics and suitable for automotive lighting, industrial machine vision, and commercial street lighting applications requiring stable component supply, AEC-Q100 qualification, and long-term production continuity.
Supply support for LT3932IUFD#PBF 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 is a global leader in high-performance analog, mixed-signal, and digital signal processing technologies, serving automotive, industrial, communications, and healthcare markets.
The LT3932IUFD#PBF belongs to Analog Devices' Silent Switcher® LED driver product line, engineered specifically for EMI-sensitive automotive and industrial lighting systems requiring precise current regulation, robust fault protection, and thermal resilience.
FAQ
What is the maximum LED string voltage supported by the LT3932IUFD#PBF?
The LT3932IUFD#PBF supports 0V to 36V LED string voltage, enabling direct drive of multi-LED strings without intermediate voltage conversion. This range is confirmed in the Absolute Maximum Ratings table and Electrical Characteristics section of the datasheet, where ISP and ISN pins tolerate up to 40V, and VOUT operates within the same domain. The FB pin monitors this voltage via external resistive divider to prevent overvoltage conditions.
Does the LT3932IUFD#PBF require an external PMOS for PWM dimming?
No - the LT3932IUFD#PBF includes both an internal PWM dimming generator (activated via RP resistor and PWM pin voltage) and a dedicated high-side PMOS gate driver (PWMTG pin). An external PMOS is optional: it is only required when using the PWMTG output for active PWM switching; otherwise, internal PWM dimming operates without any external FET.
What is the purpose of the SYNC/SPRD pin on the LT3932IUFD#PBF?
The SYNC/SPRD pin on the LT3932IUFD#PBF serves two functions: (1) synchronization - accept external clock signals (200kHz–2MHz) to align switching frequency with system timing; (2) spread-spectrum modulation - tie to INTVCC to enable frequency dithering (100%–125% range), reducing peak EMI emissions. It must be tied to GND if unused.
How does the LT3932IUFD#PBF handle LED open-circuit and short-circuit faults?
The LT3932IUFD#PBF continuously monitors FB voltage: open-circuit is detected when FB rises above 950 mV (with ISP–ISN <10 mV), and short-circuit when FB falls below 200 mV. In either case, the open-drain FAULT pin is pulled low. Fault response (hiccup vs. latch-off) is selected via external resistor on SS pin, per Applications Information section.
Can the LT3932IUFD#PBF operate with input voltages below 3.6V?
No - the LT3932IUFD#PBF has a specified minimum input voltage of 3.6V, as stated in the Electrical Characteristics table. Operation below this level is not guaranteed and may result in improper biasing of internal regulators (e.g., INTVCC, VREF) or failure to initiate switching. EN/UVLO threshold is 1.15V, but functional operation requires sufficient headroom above 3.6V for the power stage.
LT3932IUFD#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 28-WFQFN Exposed Pad
- Packaging:
- Tube
- Product Status:
- Active
- Type:
- DC DC Regulator
- Topology:
- Step-Down (Buck)
- Internal Switch(s):
- Yes
- Number of Outputs:
- 1
- Voltage - Supply (Min):
- 3.6V
- Voltage - Supply (Max):
- 36V
- Voltage - Output:
- -
- Current - Output / Channel:
- 2A
- 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)
LT3932IUFD#PBF FAQ
1.How can I place an order for LT3932IUFD#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT3932IUFD#PBF 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 LT3932IUFD#PBF reliable?
The price and inventory of LT3932IUFD#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT3932IUFD#PBF is usually 5 days.
3.What payment methods are accepted for LT3932IUFD#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT3932IUFD#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT3932IUFD#PBF?
LT3932IUFD#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT3932IUFD#PBF 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 LT3932IUFD#PBF?
For technical support, including LT3932IUFD#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT3932IUFD#PBF requirements.
6.How does Aetrix verify that LT3932IUFD#PBF is sourced from the original manufacturer or authorized distributors?
All LT3932IUFD#PBF 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 LT3932IUFD#PBF meets industry standards.
7.What is the process for return or replacement of LT3932IUFD#PBF?
All LT3932IUFD#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LT3932IUFD#PBF, 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 LT3932IUFD#PBF part is unused and in its original packaging.
Return procedure for LT3932IUFD#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT3932IUFD#PBF 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…
