My Inquiry
My Account
Analog Devices Inc. LT3517IFE#TRPBF
- Part No.:
- LT3517IFE#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- LED Drivers
- Package:
- 16-TSSOP (0.173", 4.40mm Width) Exposed Pad
- Datasheet:
-
LT3517IFE#TRPBF.pdf
- Description:
- IC LED DRV RGLTR PWM 16TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:1,396
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT3517IFE#TRPBF from Analog Devices (formerly Linear Technology) is a constant-frequency current-mode DC/DC LED driver IC with an internal 1.5A, 45V power switch, supporting boost, buck, and buck-boost topologies. It delivers precise constant-current regulation via 100mV high-side current sensing, enables 5000:1 true-color PWM dimming, and operates from 3V to 30V input across –40°C to 125°C. It is used in automotive lighting, display backlighting, and industrial illumination systems requiring robust open-LED protection and synchronized switching.
For engineers reviewing the LT3517IFE#TRPBF datasheet, LT3517IFE#TRPBF pinout, LT3517IFE#TRPBF application, or LT3517IFE#TRPBF equivalent, key selection criteria include its 16-pin TSSOP package, 250kHz–2.5MHz adjustable switching frequency, 100mV current sense threshold, integrated PMOS gate driver (TG), and dual-loop (voltage + current) regulation architecture for seamless CV/CC mode transition.
Technical Context
The LT3517IFE#TRPBF implements a current-mode control architecture with independent voltage and current feedback loops, where the lower of the two error amplifier outputs determines operating mode-ensuring automatic, glitch-free transition between constant-voltage (FB = 1.01V) and constant-current (VISP–VISN = 100mV) regulation. Its internal 1.5A/45V DMOS switch supports up to 97% duty cycle and integrates gate drive for an external PMOS disconnect switch via the TG pin.
Switching frequency is programmable via resistor at RT (250kHz–2.5MHz) or synchronized to an external clock at SYNC, with built-in ramp compensation and soft-start (SS pin). The CTRL pin sets LED current threshold linearly from 0 to 100mV (0–1V input), while PWM pin enables digital dimming with stored VC-state recovery for sub-2µs transient response at 2MHz fSW.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 3V to 30V continuous; withstands 40V transients - supports 12V/24V automotive rails and wide-input industrial supplies. |
| Switch Current Limit | 1.5A typical (1.9A max) - enables direct driving of multi-LED strings up to ~35W in buck configuration. |
| Current Sense Threshold | 100mV (±3mV) - minimizes power loss in sense resistor and improves accuracy over temperature. |
| Dimming Ratio | 5000:1 via PWM pin - achieves flicker-free, high-fidelity color rendering in display backlighting without current droop. |
| Operating Temp Range | –40°C to +125°C junction - qualified for under-hood automotive and industrial ambient environments. |
| Package | 16-lead plastic TSSOP - surface-mount compatible with standard reflow profiles and accessible for manual prototyping. |
| Shutdown Current | <1µA - enables ultra-low-power standby in battery-powered portable lighting systems. |
Pinout & Package
LT3517IFE#TRPBF is housed in a 16-lead plastic TSSOP package (JEDEC MO-153, 5.0mm × 4.4mm × 1.2mm), with exposed thermal pad connected internally to GND. Pin 1 is marked by a dot; pin numbering follows standard TSSOP convention (counterclockwise from top-left corner).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VIN | Main input supply rail | Accepts 3V–30V; requires local 2.2µF ceramic bypass to minimize high-frequency ripple and EMI. |
| SHDN | Enable/disable control | Logic-high (>1.2V) enables operation; logic-low (<0.45V) disables switch and reduces quiescent current to <1µA. |
| CTRL | Analog current setpoint | 0–1V input scales LED current threshold from 0 to 100mV across RSENSE, enabling 10:1 analog dimming. |
| PWM | Digital dimming control | Active-low signal disables switching and preserves VC state; supports 5000:1 dimming ratio with fast recovery. |
| SYNC | External clock input | Accepts TTL/CMOS clock; forces synchronization when RT is configured for 20% lower free-running frequency. |
| FB | Voltage loop feedback | Regulates output to 1.01V threshold; provides overvoltage protection by disabling switch if exceeded. |
| SS | Soft-start timing node | Capacitor here controls ramp rate of VC; 0.1µF yields ~1ms startup with minimal inrush current. |
| RT | Frequency programming | Resistor to GND sets oscillator frequency (250kHz–2.5MHz); must not be left floating or capacitive-loaded. |
| SW | Power switch drain | Connects to inductor/diode node; trace must be short and low-inductance to reduce EMI and switching losses. |
| PVIN | Power switch source | Internal connection to ISP; ties to high-side LED rail in buck-boost configurations. |
| ISP / ISN | High-side current sense inputs | Differential pair measuring voltage across external sense resistor; rail-to-rail input range supports full LED string compliance. |
| TG | PMOS gate driver output | Inverted PWM signal drives external PMOS disconnect switch; clamped to VISP–7V for gate protection. |
| TGEN | TG enable control | Logic-high (>1.5V) activates TG output; internal 40kΩ pull-down allows default disable when unconnected. |
| VREF | 2.0V reference output | Stable 2.0V ±20mV reference; supplies bias for CTRL, RT, and external circuitry; rated for 100µA sink/source. |
| VC | Error amplifier output | Transconductance amplifier output (550µS); RC compensation network here stabilizes both CV and CC loops. |
| GND | Signal and power ground | Single ground reference for all analog and power circuits; tied to exposed pad for thermal conduction. |
Key Features
| Feature | Design Value |
|---|---|
| True Color PWM™ Dimming | 5000:1 ratio with preserved color fidelity - achieved via VC-state retention during PWM off-time and fast loop recovery. |
| Integrated PMOS Gate Driver | TG pin delivers inverted PWM with 7V clamp - enables efficient LED string disconnect to prevent output capacitor discharge during dimming. |
| Dual-Loop Regulation | Simultaneous CV (FB) and CC (ISP/ISN) feedback - ensures stable operation across varying LED forward voltage and load conditions. |
| Open LED Protection | Automatic shutdown if ISP–ISN voltage exceeds threshold - prevents overvoltage damage to LEDs and external components. |
| Transient Input Tolerance | Withstands 40V/1s non-repetitive transients - meets ISO 7637-2 pulse 5a requirements for automotive 24V systems. |
| Adjustable Switching Frequency | 250kHz–2.5MHz via RT resistor - allows trade-off between efficiency (lower fSW) and solution size (higher fSW). |
Applications
| Automotive Headlamp Control | Industrial Display Backlighting |
|---|---|
Use Scenario: Adaptive front-lighting system (AFS) in 12V/24V vehicles requiring dynamic beam shaping and daylight-synchronized intensity control. IC Role / Device Role / Timing Role: Constant-current LED driver regulating 1–3A through high-brightness white LED arrays; synchronizes switching to vehicle CAN bus clock for EMI reduction. Use Value: Enables precise luminance control across temperature (–40°C to +125°C), withstands load-dump transients up to 40V, and supports 5000:1 dimming for glare-free night vision. | Use Scenario: High-resolution TFT-LCD backlight in medical imaging monitors demanding uniform brightness and zero flicker. IC Role / Device Role / Timing Role: Buck-mode LED driver powering parallel LED strings with 100mV current sensing and PWM dimming synchronized to display frame rate. Use Value: Delivers <±1% current matching across strings, eliminates visible PWM artifacts via true-color dimming, and maintains regulation during rapid VIN fluctuations from SMPS sources. |
| Avionic Cabin Lighting | Barcode Scanner Illumination |
Use Scenario: Redundant LED lighting in commercial aircraft cabins requiring DO-160D Section 22 lightning-induced transient immunity and extended lifetime. IC Role / Device Role / Timing Role: Constant-voltage regulated buck-boost driver powering 24V LED modules from 18–32V aircraft bus; uses CTRL pin for analog dimming via cockpit potentiometer. Use Value: Meets MIL-STD-704F input surge requirements, provides open-LED fault detection for safety-critical status reporting, and operates reliably at –40°C to +85°C ambient. | Use Scenario: High-speed handheld barcode scanner needing pulsed LED illumination synchronized to image capture for motion blur elimination. IC Role / Device Role / Timing Role: Boost-mode LED driver delivering 300mA pulses at 10kHz; uses SYNC pin to align switching edges with CMOS image sensor exposure timing. Use Value: Achieves sub-microsecond LED turn-on delay, sustains >90% efficiency at 2MHz fSW, and enables precise 100ns pulse-width control for optimal depth-of-field illumination. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LED driver applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LTC3783EFE#TRPBF | Higher 4A switch current, 60V rating, no integrated TG driver; requires external MOSFETs for disconnect function. | Better suited for high-power (>50W) LED arrays; lacks single-chip PWM+analog dimming integration. | Select when higher output power or wider input range (4.5V–60V) is required; accept added BOM cost and layout complexity. |
| MAX16820ATP+ | Fixed 1MHz fSW, 2.5A switch, no SYNC or RT adjustment; only 1000:1 PWM dimming; TSSOP-20 package. | Targeted at cost-sensitive consumer lighting; lacks adjustable frequency and dual-loop flexibility. | Choose for simpler, fixed-frequency designs where 5000:1 dimming and CV/CC auto-transition are not needed. |
Compared with LTC3783EFE#TRPBF and MAX16820ATP+, the LT3517IFE#TRPBF uniquely combines 5000:1 PWM dimming, integrated TG driver, and seamless CV/CC mode switching in a compact 16-pin TSSOP-making it optimal for space-constrained, high-fidelity lighting systems requiring automotive-grade reliability.
Availability
LT3517IFE#TRPBF is available at Aetrix Electronics and suitable for automotive lighting, industrial display backlighting, and avionic cabin illumination requiring stable component supply, long-term lifecycle support, and guaranteed RoHS-compliant manufacturing.
Supply support for LT3517IFE#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) is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, formed through the acquisition of Linear Technology in 2017.
The LT3517IFE#TRPBF belongs to ADI's precision power management portfolio, designed specifically for high-efficiency, high-reliability LED lighting in automotive, industrial, and aerospace applications where thermal robustness and EMI control are critical.
FAQ
What is the maximum input voltage rating for LT3517IFE#TRPBF during continuous operation?
The LT3517IFE#TRPBF supports continuous input voltage up to 30V, with absolute maximum rating of 40V for nonrepetitive 1-second transients. This allows safe operation in 24V automotive systems subject to load-dump events per ISO 7637-2, provided proper input filtering and thermal design are implemented for the LT3517IFE#TRPBF.
How does the LT3517IFE#TRPBF achieve 5000:1 PWM dimming without color shift?
The LT3517IFE#TRPBF achieves 5000:1 True Color PWM™ dimming by preserving the VC node's charge state during PWM low periods-enabling immediate current restoration upon PWM high transition. Combined with rail-to-rail current sense amplifier operation and stored error amplifier output, this eliminates settling delays and maintains consistent LED forward voltage, preventing perceptible color shift in the LT3517IFE#TRPBF.
Can LT3517IFE#TRPBF operate in buck, boost, and buck-boost modes with the same PCB layout?
Yes-the LT3517IFE#TRPBF supports all three topologies using shared core components (inductor, diode, sense resistor), but requires topology-specific placement of input/output capacitors and feedback resistors. The LT3517IFE#TRPBF pinout and internal architecture allow reconfiguration via external component routing, not IC replacement, making it ideal for platform-based lighting designs.
What is the purpose of the TG and TGEN pins on LT3517IFE#TRPBF?
The TG pin is an inverted PWM output that drives an external PMOS transistor to disconnect the LED string during PWM off-time, preventing output capacitor discharge and improving dimming fidelity. The TGEN pin enables or disables the TG driver-logic-high activates it; internal 40kΩ pull-down keeps TG inactive when TGEN is unconnected. Both functions are integral to the LT3517IFE#TRPBF's high-ratio dimming capability.
Does LT3517IFE#TRPBF require external compensation components, and where are they connected?
Yes-the LT3517IFE#TRPBF requires external RC compensation at the VC pin to stabilize both constant-current and constant-voltage loops. A typical configuration uses a 10nF capacitor from VC to GND; a series resistor may be added to increase slew rate during fast transients. No compensation is needed at FB or CTRL-these are high-impedance inputs optimized for direct connection in the LT3517IFE#TRPBF.
LT3517IFE#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- True Color PWM™
- Package/Case:
- 16-TSSOP (0.173", 4.40mm Width) Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Type:
- DC DC Regulator
- Topology:
- Step-Down (Buck), Step-Up (Boost)
- Internal Switch(s):
- Yes
- Number of Outputs:
- 1
- Voltage - Supply (Min):
- 3V
- Voltage - Supply (Max):
- 30V
- Voltage - Output:
- -
- Current - Output / Channel:
- 1.5A (Switch)
- Frequency:
- 250kHz ~ 2.5MHz
- Dimming:
- Analog, PWM
- Applications:
- Backlight
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-TSSOP-EP
LT3517IFE#TRPBF FAQ
1.How can I place an order for LT3517IFE#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT3517IFE#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 LT3517IFE#TRPBF reliable?
The price and inventory of LT3517IFE#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT3517IFE#TRPBF is usually 5 days.
3.What payment methods are accepted for LT3517IFE#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT3517IFE#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT3517IFE#TRPBF?
LT3517IFE#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT3517IFE#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 LT3517IFE#TRPBF?
For technical support, including LT3517IFE#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT3517IFE#TRPBF requirements.
6.How does Aetrix verify that LT3517IFE#TRPBF is sourced from the original manufacturer or authorized distributors?
All LT3517IFE#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 LT3517IFE#TRPBF meets industry standards.
7.What is the process for return or replacement of LT3517IFE#TRPBF?
All LT3517IFE#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LT3517IFE#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 LT3517IFE#TRPBF part is unused and in its original packaging.
Return procedure for LT3517IFE#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT3517IFE#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…
