My Inquiry
My Account
Analog Devices Inc. LT3741IFE-1#TRPBF
- Part No.:
- LT3741IFE-1#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- DC DC Switching Controllers
- Package:
- 20-TSSOP (0.173", 4.40mm Width) Exposed Pad
- Datasheet:
-
LT3741IFE-1#TRPBF.pdf
- Description:
- IC REG CTRLR BUCK 20TSSOP
- Quantity:
- Payment:
- Shipping:
Inventory:3,856
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT3741IFE-1#TRPBF from Analog Devices (formerly Linear Technology) is a fixed-frequency synchronous step-down DC/DC controller optimized for high-power constant-current and constant-voltage regulation up to 20A output. It features average current-mode control, ±6% current regulation accuracy, ±1.5% voltage regulation accuracy, and supports input voltages from 6V to 36V with output voltage range up to (VIN – 2V). It is used in super-capacitor charging and industrial power supplies requiring precise current limiting and extreme short-circuit protection.
For engineers reviewing the LT3741IFE-1#TRPBF datasheet, LT3741IFE-1#TRPBF pinout, LT3741IFE-1#TRPBF application, or LT3741IFE-1#TRPBF equivalent, key selection considerations include its dual analog control inputs (CTRL1/CTRL2), thermal current derating capability, programmable switching frequency (200kHz–1MHz), 20-pin TSSOP package with exposed pad, and integrated 5V VCC_INT regulator for gate drive support.
Technical Context
The LT3741IFE-1#TRPBF implements average current-mode control using internal gm amplifiers (375–625 µA/V for current loop, 800 µA/V for voltage loop) and a 2V buffered reference (±1% over temperature). Its architecture enables sourcing and sinking of inductor current - though the -1 variant disables sinking, making it suitable for parallel operation and applications where bidirectional current is unnecessary.
It integrates dual gate drivers (HG/LG) with non-overlap timing (60–100 ns), programmable soft-start (11 µA charging current), and overvoltage lockout triggered at FB ≥1.5V (13 µs shutdown). The CTRL1/CTRL2 pins accept 0–1.5V analog inputs to set regulated current, with internal clamping and 23 mV overcurrent offset referenced to SENSE+–SENSE–.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 6V to 36V - supports wide industrial input rails including 12V, 24V, and 36V systems without external pre-regulation. |
| Output Current Accuracy | ±6% - ensures repeatable current regulation across temperature and line/load variations for LED drivers or battery charging. |
| Voltage Regulation Accuracy | ±1.5% - maintains stable output voltage during CV mode, critical for precision power sources and super-capacitor charging termination. |
| Switching Frequency Range | 200 kHz to 1 MHz - adjustable via RT resistor or external SYNC signal, enabling optimization of size, efficiency, and EMI performance. |
| CTRL Input Range | 0 V to 1.5 V - maps linearly to 0–20 A output current (with external sense resistor), enabling analog dimming or thermal derating via CTRL2. |
| Shutdown Quiescent Current | <1 µA - minimizes system standby power loss in always-on industrial or automotive auxiliary supplies. |
| Package | 20-Lead Plastic TSSOP with exposed thermal pad - provides robust thermal performance (θJA = 38°C/W) and compatibility with standard PCB assembly processes. |
Pinout & Package
LT3741IFE-1#TRPBF is housed in a 20-lead plastic TSSOP package with an exposed thermal pad (Pin 21) that must be soldered to PCB ground for thermal and electrical integrity. The package operates from –40°C to +125°C junction temperature.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| Pin 1 (VCC_INT) | Internal 5V regulator output | Supplies gate drive and internal circuitry; current-limited to 50 mA; must be bypassed with 1 µF ceramic capacitor. |
| Pin 2 & 7 & 16 (GND) | Ground reference | Multiple GND pins reduce impedance; exposed pad (Pin 21) is GND and mandatory for thermal management. |
| Pin 3 (VIN) | Main power input | Accepts 6–36 V; requires local 4.7 µF low-ESR bypass capacitor to minimize noise and ripple. |
| Pin 4 (EN/UVLO) | Enable and undervoltage lockout | Turns on core at 1.55 V with 130 mV hysteresis; full shutdown below ~0.5 V; supports programmable UVLO via external resistor divider. |
| Pin 5 (VREF) | 2.0 V buffered reference | Stable 2 V output (±1%) capable of driving 0.5 mA; used to bias CTRL1/CTRL2 via resistor dividers. |
| Pin 6 (CTRL2) | Thermal current control input | Analog input (0–1.5 V) to dynamically reduce regulated current based on temperature feedback (e.g., NTC network). |
| Pin 8 (CTRL1) | Primary current setpoint input | 0–1.5 V analog input sets maximum regulated current; internally clamped; defines overcurrent threshold with +23 mV offset. |
| Pin 9 (SS) | Soft-start control | Charged at 11 µA; controls ramp rate of regulated current during startup to limit inrush and stress on FETs/capacitors. |
| Pin 10 (FB) | Voltage feedback and OVP sense | 1.21 V regulation threshold; triggers 13 µs shutdown if voltage exceeds 1.5 V (25% above nominal), protecting downstream loads. |
| Pin 11 & 12 (SENSE+ / SENSE–) | Current sense differential inputs | Measure voltage drop across external sense resistor (RS); common-mode range extends to VIN – 2 V; enable accurate average current regulation. |
| Pin 13 (VC) | Current loop compensation | Connects to compensation network (e.g., 20–50 kΩ resistor + 2–5 nF capacitor) to stabilize average current-mode control loop. |
| Pin 14 (RT) | Frequency setting | Resistor-to-ground sets fSW from 200 kHz to 1 MHz; pin current-limited to 60 µA; avoid floating connection. |
| Pin 15 (SYNC) | External clock synchronization | Allows frequency locking to external source; RT resistor must be set for 20% lower internal frequency to prevent jitter or instability. |
| Pin 17 (HG) | High-side gate driver output | Drives external high-side N-MOSFET; pull-up/pull-down impedances are 2.3 Ω / 1.3 Ω; supports fast switching with minimal dead-time risk. |
| Pin 18 (LG) | Low-side gate driver output | Drives external low-side N-MOSFET; pull-up/pull-down impedances are 2.3 Ω / 1.0 Ω; complements HG for synchronous buck topology. |
| Pin 19 (CBOOT) | Floating high-side supply | Provides ~5 V bootstrap supply for HG driver; requires Schottky diode from VCC_INT to CBOOT and ceramic capacitor to SW node. |
| Pin 20 (SW) | Switch node | Connects high-side drain, low-side source, and inductor; high dv/dt node requiring careful layout and minimized trace area. |
Key Features
| Feature | Design Value |
|---|---|
| Dual analog current control (CTRL1 + CTRL2) | Enables independent thermal derating and priority-based current limiting - e.g., CTRL2 reduces output current when temperature rises, while CTRL1 sets baseline limit. |
| Accurate ±6% current regulation over temperature | Ensures consistent load current delivery across –40°C to +125°C, critical for LED arrays, laser diodes, and electrochemical systems. |
| Integrated 5V VCC_INT regulator | Eliminates need for external bias supply; powers internal logic, gate drivers, and CBOOT charging - simplifies BOM and improves reliability. |
| Programmable overvoltage lockout (1.5 V at FB) | Prevents damage to sensitive loads (e.g., supercaps, batteries) by halting switching for 13 µs upon overvoltage detection, allowing safe inductor discharge. |
| 200 kHz–1 MHz switching frequency | Supports compact magnetics and low-profile capacitors while maintaining >94% peak efficiency; RT/SYNC flexibility aids EMI compliance. |
| Thermal shutdown with 8°C hysteresis | Protects against sustained overload or poor heatsinking by disabling all switching at 163°C and resuming only after cooling to 155°C. |
Applications
| Super-Capacitor Charging | Industrial Constant-Current Source |
|---|---|
|
Use Scenario: Rapid charging of 10–50 F supercapacitor banks from 24 V industrial bus to 5–12 V final voltage. IC Role / Device Role / Timing Role: Primary current-regulating controller in synchronous buck topology; manages CC→CV transition and OVP cutoff. Use Value: Delivers up to 20 A with ±6% current accuracy and automatic voltage foldback, preventing electrolyte decomposition and extending capacitor life. |
Use Scenario: Precision 0–20 A current source for electroplating, sensor excitation, or magnetic coil control in factory automation. IC Role / Device Role / Timing Role: Average current-mode controller with analog-set current limit and thermal derating via CTRL2. Use Value: Maintains stable current under varying load impedance and ambient temperature, eliminating need for external DAC or op-amp feedback loops. |
| LED Driver for High-Power Arrays | Parallel Power Supply Module |
|
Use Scenario: Driving multi-string 50 W+ LED arrays in architectural or horticultural lighting with dimming and thermal headroom management. IC Role / Device Role / Timing Role: Constant-current controller with analog dimming (CTRL1) and active thermal rollback (CTRL2) to prevent LED junction overheating. Use Value: Enables smooth 0–100% dimming while automatically reducing current as heatsink temperature rises - preserving lumen maintenance and color stability. |
Use Scenario: Building scalable 40 A+ power rail using two LT3741IFE-1#TRPBF controllers in interleaved, current-sharing configuration. IC Role / Device Role / Timing Role: Synchronous buck controller with SYNC pin support and identical RT programming for phase alignment and ripple cancellation. Use Value: Doubles output current capacity while reducing input/output ripple by 50%, easing EMI filter design and improving dynamic response. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar high-current synchronous buck controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LTC3891EFE#PBF | Single-output, 6–40 V input, supports up to 25 A with similar current-mode control but lacks dual CTRL inputs and dedicated thermal derating path. | No integrated CTRL2-style thermal control; requires external circuitry for temperature-based current reduction. | Choose LTC3891EFE#PBF when higher input voltage (up to 40 V) and slightly higher current capability are needed, and thermal derating is handled externally. |
| MP2451DT-LF-Z | Monolithic 2A buck converter (not controller); integrates MOSFETs, lacks current-sense inputs, no analog current programming, max 36 V input. | Not suitable for >5 A or external FET designs; cannot replicate LT3741IFE-1#TRPBF's 20 A capability or precision current regulation. | Consider MP2451DT-LF-Z only for low-power, cost-sensitive applications where integrated FETs and simplicity outweigh current accuracy and scalability needs. |
Compared with LTC3891EFE#PBF and MP2451DT-LF-Z, the LT3741IFE-1#TRPBF uniquely delivers factory-trimmed ±6% current regulation, dual analog control inputs for hardware-based thermal management, and native support for parallel operation - making it the preferred choice for high-reliability, high-current industrial and energy storage applications.
Availability
LT3741IFE-1#TRPBF is available at Aetrix Electronics and suitable for industrial power supplies, super-capacitor charging systems, and high-current LED drivers requiring stable component supply, long-term lifecycle support, and traceable sourcing.
Supply support for LT3741IFE-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 (ADI), formed through the acquisition of Linear Technology in 2017, is a global leader in high-performance analog, mixed-signal, and power management ICs.
The LT3741IFE-1#TRPBF belongs to ADI's high-current DC/DC controller product line, designed specifically for precision constant-current applications such as supercapacitor charging, LED drivers, and industrial current sources where accuracy, thermal resilience, and scalability are critical.
FAQ
What is the key functional difference between LT3741IFE-1#TRPBF and the standard LT3741IFE#TRPBF?
The LT3741IFE-1#TRPBF is the -1 variant, which disables the current-sinking capability present in the base LT3741. This makes it optimized for parallel operation and applications where unidirectional (source-only) current flow is sufficient - such as supercapacitor charging or LED driving. The LT3741IFE#TRPBF supports both sourcing and sinking, enabling bidirectional current control in regenerative or active-load applications. Both share identical pinout, package, and control architecture.
Can LT3741IFE-1#TRPBF regulate output current down to zero amps?
Yes, the LT3741IFE-1#TRPBF can regulate output current down to 0 A by applying 0 V to the CTRL1 pin. Its current control range is linear from 0 V to 1.5 V, corresponding to 0 A up to the maximum set by the external sense resistor (e.g., 20 A with 2.5 mΩ). The CTRL2 pin can further reduce this level dynamically - for example, to 0 A under thermal fault conditions - providing fail-safe current disable capability.
What is the purpose of the exposed thermal pad (Pin 21) on the LT3741IFE-1#TRPBF TSSOP package?
The exposed thermal pad (Pin 21) on the LT3741IFE-1#TRPBF is electrically and thermally connected to GND. It must be soldered to a PCB copper pour tied to system ground to ensure proper thermal dissipation (θJA = 38°C/W) and electrical stability. Omitting this connection risks thermal shutdown, reduced efficiency, and potential oscillation due to elevated junction temperature and ground impedance.
How does the overvoltage protection (OVP) function on LT3741IFE-1#TRPBF?
The LT3741IFE-1#TRPBF monitors output voltage via the FB pin. When FB voltage reaches 1.5 V - approximately 25% above the 1.21 V regulation threshold - the OVP circuit triggers and disables switching for exactly 13 µs. During this time, the inductor current decays safely. After 13 µs, normal regulation resumes unless the overvoltage condition persists. This cycle repeats until the fault clears, protecting downstream capacitors and loads from overvoltage stress.
Is LT3741IFE-1#TRPBF compatible with ceramic output capacitors?
Yes, the LT3741IFE-1#TRPBF is fully compatible with ceramic output capacitors. Its average current-mode control loop and VC compensation pin allow stable operation with low-ESR ceramics. Typical designs use 10–150 µF X7R/X5R ceramics in parallel with bulk aluminum polymer capacitors for optimal transient response and ripple suppression. Layout best practices - including short, low-inductance paths from SW and GND to the output capacitor - are essential to maintain stability.
LT3741IFE-1#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 20-TSSOP (0.173", 4.40mm Width) Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Output Type:
- Transistor Driver
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Number of Outputs:
- 1
- Output Phases:
- 1
- Voltage - Supply (Vcc/Vdd):
- 6V ~ 36V
- Frequency - Switching:
- 200kHz ~ 1MHz
- Duty Cycle (Max):
- -
- Synchronous Rectifier:
- Yes
- Clock Sync:
- Yes
- Serial Interfaces:
- -
- Control Features:
- Enable, Frequency Control, Soft Start
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 20-TSSOP-EP
LT3741IFE-1#TRPBF FAQ
1.How can I place an order for LT3741IFE-1#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT3741IFE-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 LT3741IFE-1#TRPBF reliable?
The price and inventory of LT3741IFE-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 LT3741IFE-1#TRPBF is usually 5 days.
3.What payment methods are accepted for LT3741IFE-1#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT3741IFE-1#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT3741IFE-1#TRPBF?
LT3741IFE-1#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT3741IFE-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 LT3741IFE-1#TRPBF?
For technical support, including LT3741IFE-1#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT3741IFE-1#TRPBF requirements.
6.How does Aetrix verify that LT3741IFE-1#TRPBF is sourced from the original manufacturer or authorized distributors?
All LT3741IFE-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 LT3741IFE-1#TRPBF meets industry standards.
7.What is the process for return or replacement of LT3741IFE-1#TRPBF?
All LT3741IFE-1#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LT3741IFE-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 LT3741IFE-1#TRPBF part is unused and in its original packaging.
Return procedure for LT3741IFE-1#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT3741IFE-1#TRPBF Tags
-
UCC28C45DR
Texas Instruments
-
UCC28C40DR
Texas Instruments
-
UCC28C43DR
Texas Instruments
-
ZXSC410E6TA
Diodes Incorporated
-
LM3524DMX/NOPB
Texas Instruments
-
LM3489MMX/NOPB
Texas Instruments
-
MIC2102YML-TR
Microchip Technology
-
LM5148RGYR
Texas Instruments
-
TL598CDR
Texas Instruments
-
LM5155DSSR
Texas Instruments
-
LM25085MYX/NOPB
Texas Instruments
-
UCC2813DTR-0
Texas Instruments
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…
