My Inquiry
My Account
Analog Devices Inc. LTC3775IMSE#PBF
- Part No.:
- LTC3775IMSE#PBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- DC DC Switching Controllers
- Package:
- 16-TFSOP (0.118", 3.00mm Width) Exposed Pad
- Datasheet:
-
LTC3775IMSE#PBF.pdf
- Description:
- IC REG CTRLR BUCK 16MSOP
- Quantity:
- Payment:
- Shipping:
Inventory:3,621
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC3775IMSE#PBF from Analog Devices (formerly Linear Technology) is a high-efficiency, voltage-mode synchronous step-down DC/DC controller designed for wide-input industrial and telecom power supplies. It operates from 4.5V to 38V input, delivers output down to 0.6V, supports 250kHz–1MHz programmable switching frequency, features 30ns minimum on-time, and uses RDS(ON) or sense-resistor current sensing for precise cycle-by-cycle peak current limiting.
For engineers reviewing the LTC3775IMSE#PBF datasheet, LTC3775IMSE#PBF pinout, LTC3775IMSE#PBF application, or LTC3775IMSE#PBF equivalent, key selection considerations include its 16-lead MSOP package with exposed PGND pad, ±0.75% reference accuracy over temperature, line feedforward compensation for fast transient response, and dual-mode operation (pulse-skipping or forced continuous conduction).
Technical Context
The LTC3775IMSE#PBF implements leading-edge modulation voltage-mode control with a patented line feedforward circuit that maintains constant modulator gain across input voltage variations, enabling stable loop behavior and rapid line transient response. Its error amplifier delivers 25MHz gain-bandwidth and ±0.75% reference accuracy, supporting Type 3 compensation for robust phase margin in high-step-down applications.
It integrates dual high-current gate drivers (TG/BG) with 1.5Ω/1.0Ω pull-down and 2.5Ω/2.5Ω pull-up on-resistances, enabling direct drive of N-channel MOSFETs without external buffers. Cycle-by-cycle current limiting is configurable via ILIMT (topside) and ILIMB (bottom side) pins, with internal 100μA sink and 10μA source currents for accurate external resistor programming.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 4.5V to 38V - supports 12V/24V/28V industrial and telecom rails with 40V absolute max rating. |
| Output Voltage Range | 0.6V to 0.8×VIN - enables low-voltage CPU/GPU core supplies with tight regulation at 0.6V ±0.75%. |
| Switching Frequency | 250kHz to 1MHz - user-programmable via FREQ pin resistor; allows optimization of size, efficiency, and EMI. |
| Min On-Time | <30ns - enables high step-down ratios (e.g., 24V→1.2V at 500kHz = 5% duty cycle) without pulse skipping. |
| Reference Accuracy | ±0.75% over –40°C to +125°C - ensures stable output regulation across automotive and industrial thermal environments. |
| Shutdown Current | 14μA typical - minimizes system standby power loss in always-on applications. |
| Package | 16-lead MSOP with exposed PGND pad - thermally enhanced for high-power density layouts; θJA = 40°C/W. |
Pinout & Package
Package: 16-lead plastic MSOP (MSE), 4.0mm × 3.0mm × 1.1mm body, exposed thermal pad (Pin 17) connected to PGND and required to be soldered to PCB for thermal performance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| ILIMT (Pin 1 & 3) | Top MOSFET current limit set point | 100μA internal sink current; sets VIN–SENSE threshold (90–110mV) via external resistor to VIN. |
| ILIMB (Pin 2 & 4) | Bottom MOSFET current limit set point | 10μA internal source current; sets PGND–SW threshold (80–120mV) via external resistor to SGND. |
| FB (Pin 3 & 5) | Error amplifier inverting input | Connects to VOUT divider; virtual ground node for precision feedback with 50nA input bias current. |
| COMP (Pin 4 & 6) | Error amplifier output | Drives Type 3 compensation network; sources/sinks up to ±60mA for fast transient recovery. |
| SS (Pin 5 & 7) | Soft-start control | 1μA internal current source charges external capacitor; regulates VOUT ramp from 0V to final value. |
| FREQ (Pin 6 & 8) | Oscillator frequency set | Resistor to SGND programs 250kHz–1MHz; tolerance directly impacts switching frequency accuracy. |
| SGND (Pin 7 & 9) | Signal ground reference | Kelvin return for FB, SS, COMP, MODE/SYNC; must be isolated from PGND to avoid noise coupling. |
| BG (Pin 8 & 10) | Bottom gate driver output | Drives bottom N-MOSFET gate from PGND to INTVCC (5.2V); 1.0Ω pull-down ensures fast turn-off. |
| INTVCC (Pin 9 & 11) | Internal 5.2V LDO output | Powers gate drivers and control logic; requires ≥4.7μF X5R ceramic bypass to PGND. |
| SENSE (Pin 10 & 12) | Top MOSFET current sense input | Accepts RDS(ON) voltage drop (SW-to-VIN) or sense resistor voltage for accurate current monitoring. |
| VIN (Pin 11 & 13) | Main input supply | 4.5V–38V input; bypassed to PGND with ≥1μF X5R ceramic capacitor for stability and noise suppression. |
| SW (Pin 12 & 14) | Switch node connection | Connects to source of top MOSFET; used for bottom-side current sensing and zero-cross detection. |
| TG (Pin 13 & 15) | Top gate driver output | Floating driver powered by BOOST; drives top N-MOSFET gate with 2.5Ω pull-down and 2.5Ω pull-up. |
| BOOST (Pin 14 & 16) | Top gate driver bootstrap supply | Decoupled to SW with 0.1μF ceramic; forms charge-pump with Schottky diode from INTVCC for high-side drive. |
| MODE/SYNC (Pin 15 & 1) | Operation mode select / sync input | Pull <1.2V for forced continuous mode; pull >1.2V for pulse-skipping; accepts external clock for synchronization. |
| RUN/SHDN (Pin 16 & 2) | Enable/shutdown control | 1.22V enable threshold; <0.74V forces shutdown with <14μA quiescent current; internal 1μA pull-up enables default start. |
| PGND (Exposed Pad) | Power ground return | Return path for BG driver and VIN/INTVCC bypass caps; electrically isolated from SGND; must be soldered to PCB plane. |
Key Features
| Feature | Design Value |
|---|---|
| Line feedforward compensation | Maintains constant modulator gain across 4.5V–38V input range, eliminating input-dependent loop gain variation and improving line transient response. |
| Low 30ns minimum on-time | Enables high step-down ratios (e.g., 24V→1.2V at 500kHz) without requiring pulse-skipping mode, preserving ripple and EMI predictability. |
| RDS(ON) or sense-resistor current sensing | Eliminates current-sense resistor losses while retaining option for higher accuracy via external resistor; supports both top and bottom MOSFET sensing. |
| Programmable soft-start | External capacitor on SS pin provides linear VOUT ramp; prevents inrush current and output overshoot during power-up. |
| Synchronizable fixed-frequency operation | Free-running frequency set from 250kHz–1MHz or locked to external clock, enabling deterministic EMI management in dense systems. |
| Overvoltage protection (OVP) | Dedicated MAX comparator disables TG and enables BG on >10% VOUT overvoltage, protecting downstream loads without external components. |
Applications
| Telecom Power Supply | Industrial PLC Power |
|---|---|
|
Use Scenario: 48V telecom rectifier output converted to 3.3V/5V for baseband processing and interface ICs. IC Role / Device Role / Timing Role: Primary synchronous buck controller regulating intermediate bus voltage with fast line transients from varying AC line conditions. Use Value: 30ns min on-time enables 48V→3.3V conversion at 500kHz (6.9% duty cycle); line feedforward ensures <50μs recovery from 10V line step. |
Use Scenario: 24V factory automation rail stepped down to 1.2V for FPGA core logic in programmable logic controllers. IC Role / Device Role / Timing Role: High-accuracy voltage-mode controller delivering tightly regulated low-voltage supply with ±0.75% reference stability over –40°C to +85°C. Use Value: ±0.75% VREF accuracy and Type 3 compensation ensure stable 1.2V output under 0–15A load steps; exposed PGND pad sustains 3W dissipation. |
| Automotive Infotainment | Point-of-Load Server Supply |
|
Use Scenario: 12V vehicle battery rail converted to 1.0V for SoC cores in head-unit infotainment systems. IC Role / Device Role / Timing Role: Automotive-grade (–40°C to +125°C) synchronous controller with robust UVLO hysteresis and OVP for safety-critical subsystems. Use Value: RUN/SHDN pin provides 1.22V enable threshold with 4μA hysteresis; OVP shuts down TG within 100ns on >10% overvoltage, meeting ASIL-B requirements. |
Use Scenario: 12V server backplane supplying 0.85V to GPU memory with high current density and strict ripple limits. IC Role / Device Role / Timing Role: High-frequency (1MHz) buck controller minimizing inductor size while maintaining <10mVpp ripple via forced CCM and precise current limiting. Use Value: 1MHz operation reduces inductor volume by 50% vs 500kHz; ILIMT/ILIMB pins allow independent top/bottom current limit tuning for asymmetric MOSFET designs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar synchronous step-down controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MP2918GQ-Z | Current-mode control; 4.5V–32V input; 35ns min on-time; integrated MOSFET drivers; no RDS(ON) sensing. | Requires external current-sense resistor; lacks line feedforward; lower max input voltage limits 36V+ telecom use. | Prefer for cost-sensitive, lower-power (<10A) applications where current-mode simplicity outweighs line transient performance needs. |
| ISL81601FRZ-T7A | Voltage-mode control; 4.5V–60V input; 45ns min on-time; dual-phase capable; supports PMBus telemetry. | Higher pin count (32-QFN); requires external compensation; no integrated soft-start timer; more complex layout. | Prefer for ultra-wide input (e.g., 48V PoE++ or 60V industrial) or multi-phase scaling; not drop-in due to package and feature mismatch. |
Compared with MP2918GQ-Z and ISL81601FRZ-T7A, the LTC3775IMSE#PBF offers superior line transient response via line feedforward, tighter reference accuracy (±0.75% vs ±1%), and true RDS(ON) sensing-making it optimal for high-reliability, high-step-down industrial and telecom converters where precision and stability are critical.
Availability
LTC3775IMSE#PBF is available at Aetrix Electronics and suitable for telecom power supplies, industrial PLCs, and automotive infotainment systems requiring stable component supply with guaranteed long-term availability and full temperature-grade support.
Supply support for LTC3775IMSE#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 acquired Linear Technology in 2017 and maintains full product support, documentation, and manufacturing continuity for all Linear power management ICs.
The LTC3775IMSE#PBF belongs to Linear's high-performance synchronous buck controller family, engineered for demanding industrial, telecom, and automotive power conversion where wide input range, fast transient response, and precision regulation are essential.
FAQ
What is the operating temperature range for the LTC3775IMSE#PBF?
The LTC3775IMSE#PBF is rated for operation from –40°C to +125°C junction temperature. This industrial-grade temperature range is validated per Analog Devices' characterization and statistical process controls, making it suitable for under-hood automotive and high-ambient industrial environments where thermal reliability is critical. The MSOP package's exposed PGND pad must be soldered to maximize thermal performance.
Does the LTC3775IMSE#PBF support RDS(ON) current sensing on both high-side and low-side MOSFETs?
Yes, the LTC3775IMSE#PBF supports RDS(ON) current sensing on the high-side MOSFET via the SENSE pin (connected to the switch node), and also allows bottom-side sensing through dedicated ILIMB pin configuration. This dual-path capability eliminates sense resistors while preserving accuracy, reducing board area and conduction losses compared to traditional shunt-based solutions.
How does the line feedforward compensation in the LTC3775IMSE#PBF improve transient response?
The line feedforward circuit in the LTC3775IMSE#PBF dynamically adjusts the PWM comparator's sawtooth amplitude in proportion to VIN, canceling input-voltage-dependent gain variation in the modulator. This results in consistent loop gain across 4.5V–38V input, enabling sub-50μs recovery from large line steps-critical for telecom rectifiers and variable-battery systems where input instability is common.
Can the LTC3775IMSE#PBF be synchronized to an external clock, and what is the acceptable frequency range?
Yes, the LTC3775IMSE#PBF can be synchronized to an external clock applied to the MODE/SYNC pin. It locks to an external signal within ±20% of its free-running frequency (e.g., if programmed to 500kHz, sync range is 400kHz–600kHz). This enables deterministic EMI reduction in multi-rail systems and avoids beat frequencies between switching regulators.
What is the purpose of the exposed pad (Pin 17) on the LTC3775IMSE#PBF MSOP package?
The exposed pad (Pin 17) on the LTC3775IMSE#PBF is electrically connected to PGND and serves as the primary thermal path for heat dissipation. It must be soldered to a dedicated PCB copper plane to achieve the specified θJA = 40°C/W. Failure to solder this pad significantly degrades thermal performance and may cause premature thermal shutdown under sustained load conditions.
LTC3775IMSE#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- PolyPhase®
- Package/Case:
- 16-TFSOP (0.118", 3.00mm Width) Exposed Pad
- Packaging:
- Tube
- 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):
- 4.5V ~ 38V
- Frequency - Switching:
- 250kHz ~ 1MHz
- Duty Cycle (Max):
- 90%
- Synchronous Rectifier:
- Yes
- Clock Sync:
- Yes
- Serial Interfaces:
- -
- Control Features:
- Current Limit, Enable, Frequency Control, Soft Start
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-MSOP-EP
LTC3775IMSE#PBF FAQ
1.How can I place an order for LTC3775IMSE#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC3775IMSE#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 LTC3775IMSE#PBF reliable?
The price and inventory of LTC3775IMSE#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC3775IMSE#PBF is usually 5 days.
3.What payment methods are accepted for LTC3775IMSE#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC3775IMSE#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC3775IMSE#PBF?
LTC3775IMSE#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC3775IMSE#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 LTC3775IMSE#PBF?
For technical support, including LTC3775IMSE#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC3775IMSE#PBF requirements.
6.How does Aetrix verify that LTC3775IMSE#PBF is sourced from the original manufacturer or authorized distributors?
All LTC3775IMSE#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 LTC3775IMSE#PBF meets industry standards.
7.What is the process for return or replacement of LTC3775IMSE#PBF?
All LTC3775IMSE#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC3775IMSE#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 LTC3775IMSE#PBF part is unused and in its original packaging.
Return procedure for LTC3775IMSE#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC3775IMSE#PBF 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…
