My Inquiry
My Account
Analog Devices Inc. LTC3774EUHE#PBF
- Part No.:
- LTC3774EUHE#PBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- DC DC Switching Controllers
- Package:
- 36-WFQFN Exposed Pad
- Datasheet:
-
LTC3774EUHE#PBF.pdf
- Description:
- IC REG CTRLR BUCK 36QFN
- Quantity:
- Payment:
- Shipping:
Inventory:2,320
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC3774EUHE#PBF from Analog Devices is a dual-phase, polyphase current-mode synchronous step-down controller optimized for sub-milliohm DCR sensing with 0.6V to 3.5V output regulation, 4.5V–38V input range, and programmable 200kHz–1.2MHz switching frequency. It drives external MOSFETs or power blocks in high-current CPU/GPU VRMs.
For engineers reviewing the LTC3774EUHE#PBF datasheet, LTC3774EUHE#PBF pinout, LTC3774EUHE#PBF application, or LTC3774EUHE#PBF equivalent, key selection criteria include DCR temperature compensation support, dual differential remote sense amplifiers, phase-lockable operation up to 12-phase paralleling, and ±0.75% total DC output error over temperature.
Technical Context
The LTC3774EUHE#PBF implements a proprietary dual-channel current-mode architecture with separate AC/DC current sense paths (SNSA+/SNSD+) to enhance SNR for ultra-low-DCR inductors (down to 0.2mΩ). Each channel features independent ITH-based peak current control, soft recovery from overcurrent, and hiccup-mode protection.
It integrates dual 0.6V reference-regulated feedback loops with ±0.75% total DC error, programmable current sense threshold (10–30mV in 5mV steps via ILIM pins), and internal soft-start with 600µs ramp time. Phase relationships between channels and CLKOUT are set by PHSMD voltage (0V to INTVCC), enabling precise multiphase synchronization.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VIN Range | 4.5V to 38V - supports wide-input industrial, telecom, and server power rails without pre-regulation. |
| VOUT Range | 0.6V to 3.5V - covers core logic, GPU, ASIC, and memory supply requirements with tight regulation. |
| Current Sense Threshold | Programmable 10mV–30mV in 5mV steps - enables accurate current limiting with sub-milliohm DCR sense elements. |
| Switching Frequency | 200kHz to 1.2MHz - selectable via FREQ pin resistor; balances efficiency vs. component size in high-density designs. |
| Total DC Output Error | ±0.75% over –40°C to 125°C - ensures stable output under thermal stress without recalibration. |
| Remote Sense Accuracy | Dual differential amplifiers with ±0.75% max error - eliminates IR drop errors across PCB traces and connectors. |
| Phase Support | Up to 12-phase operation via daisy-chained CLKOUT/PLLIN - reduces input/output ripple and improves transient response. |
Pinout & Package
The LTC3774EUHE#PBF is housed in a 36-lead (5mm × 6mm) plastic QFN package with exposed thermal pad (Pin 37 = GND), requiring soldering to PCB ground for thermal and electrical performance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VIN (Pin 35) | Main input supply rail | Accepts 4.5V–38V; requires local 0.1µF–1µF decoupling to GND for noise suppression. |
| INTVCC (Pin 34) | Internal 5.5V LDO output | Powers internal circuitry; must be decoupled with ≥4.7µF low-ESR capacitor to GND - not for external biasing. |
| PGOOD1/2 (Pins 15, 14) | Open-drain power-good indicators | Pull low when respective VOUT is out of regulation (±7.5% window); enable sequencing and fault reporting. |
| SNSA1+/SNSA2+ (Pins 16, 13) | AC current sense comparator inputs | Process high-frequency inductor ripple for accurate peak current detection; bandwidth = 5×(L/DCR). |
| SNSD1+/SNSD2+ (Pins 18, 11) | DC current sense comparator inputs | Track average inductor current; filter time constant matches L/DCR for DCR-based sensing accuracy. |
| ITH1/ITH2 (Pins 27, 2) | Error amplifier output / current threshold control | Voltage sets per-phase peak inductor current; directly interfaces with compensation network (RC on ITH). |
| FREQ (Pin 31) | Frequency programming node | 20µA current source; resistor to GND sets oscillator frequency from 200kHz to 1.2MHz with ±10% tolerance. |
| MODE/PLLIN (Pin 32) | Operating mode select / PLL input | GND = forced continuous; INTVCC = pulse-skipping; float = Burst Mode; external clock = PLL sync (200kHz–1.2MHz). |
| PHSMD (Pin 30) | Phase mode configuration | Voltage selects CH1–CH2 and CH1–CLKOUT phase offsets (e.g., 0V → 180°/240°; INTVCC → 180°/60°). |
| TK/SS1/2 (Pins 24, 5) | Soft-start and tracking inputs | 1.25µA pull-up charges external capacitor; controls VOUT ramp rate or enables supply tracking. |
| ILIM1/ILIM2 (Pins 29, 36) | Current sense threshold select | Set max sense voltage (10/15/20/25/30mV) by connecting to GND, 1/4, 1/2, 3/4, or full INTVCC. |
| ITEMP1/ITEMP2 (Pins 28, 1) | DCR temperature compensation inputs | Connect to NTC thermistor near inductors to compensate for DCR drift with temperature. |
Key Features
| Feature | Design Value |
|---|---|
| Dual independent current-mode control loops | Enables true two-phase operation with separate ITH, soft-start, and overcurrent protection per channel. |
| Sub-milliohm DCR sensing with SNR enhancement | Supports 0.2mΩ inductors using dual-path (SNSA+/SNSD+) filtering - eliminates need for discrete sense resistors. |
| Programmable current limit threshold (10–30mV) | Five-step selection via ILIM pins allows precise current foldback without changing external components. |
| Dual differential remote sense amplifiers | Compensates for PCB trace resistance and connector voltage drop - maintains ±0.75% output accuracy at load. |
| Multiphase synchronization up to 12 phases | CLKOUT/PLLIN interface and PHSMD voltage control enable deterministic phase alignment across multiple controllers. |
| Hiccup-mode overcurrent recovery | Soft-recovery prevents output overshoot during short-circuit events - avoids damage to downstream loads. |
Applications
| Server CPU Voltage Regulator | AI Accelerator Power Delivery |
|---|---|
|
Use Scenario: High-current, low-voltage core supply for multi-core Xeon or EPYC processors with dynamic load steps up to 100A/µs. IC Role / Device Role / Timing Role: Dual-phase controller managing parallel power stages with phase shedding and DCR temperature compensation. Use Value: Enables <1.5% output deviation during 60A transients while maintaining <0.2mΩ DCR sensing accuracy across –40°C to 125°C. |
Use Scenario: Precision 0.8V–1.2V supply for NVIDIA A100 or AMD MI300 GPUs with strict ripple and sequencing requirements. IC Role / Device Role / Timing Role: Synchronized multiphase controller supporting 6- or 8-phase operation via CLKOUT daisy-chaining. Use Value: Reduces input RMS current by 60% and output voltage ripple by 75% compared to single-phase solutions. |
| Telecom Baseband Power System | Industrial FPGA Core Supply |
|
Use Scenario: 1.8V/40A supply for 5G massive MIMO baseband processors operating in extended temperature environments. IC Role / Device Role / Timing Role: Dual-channel controller with programmable soft-start and pre-biased start-up capability. Use Value: Supports smooth start-up into pre-charged outputs and maintains ±0.75% regulation across –40°C to 125°C ambient. |
Use Scenario: Reconfigurable 1.0V/30A supply for Xilinx Versal or Intel Agilex FPGAs with dynamic voltage scaling. IC Role / Device Role / Timing Role: Controller with TRACK/SS pins enabling voltage ramp coordination with auxiliary supplies. Use Value: Ensures monotonic power-up across core, I/O, and auxiliary rails - prevents FPGA configuration failure. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-phase synchronous buck controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MP2960GQ-Z | Single-chip dual-phase controller with integrated drivers; fixed 0.6V reference; no DCR temperature compensation. | Targeted at cost-sensitive consumer applications; lacks remote sense amplifiers and multiphase scalability beyond 2 phases. | Choose MP2960GQ-Z only for space-constrained, lower-accuracy designs where integrated drivers reduce BOM count. |
| ISL95852IRZ-T | Intel VR12.5-compliant dual-phase controller; supports SVID interface; no independent DCR sensing path. | Designed specifically for Intel CPU platforms with serial VID communication; limited to 0.5V–1.5V output range. | Choose ISL95852IRZ-T only for Intel-compatible systems requiring SVID handshake and VR12.5 compliance. |
Compared with MP2960GQ-Z and ISL95852IRZ-T, the LTC3774EUHE#PBF provides broader input/output ranges, dedicated DCR temperature compensation, and scalable multiphase support - making it uniquely suited for high-accuracy, high-current industrial and AI infrastructure power systems.
Availability
LTC3774EUHE#PBF is available at Aetrix Electronics and suitable for server VRMs, AI accelerator power delivery, telecom baseband systems, and industrial FPGA core supplies requiring stable component supply and long-term lifecycle assurance.
Supply support for LTC3774EUHE#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) is a global leader in high-performance analog, mixed-signal, and power management ICs, serving precision instrumentation, communications, and industrial markets.
The LTC3774EUHE#PBF belongs to Linear's PolyPhase® controller family, engineered for high-efficiency, high-current DC/DC conversion in datacenter, networking, and high-end computing applications where DCR sensing accuracy and thermal stability are critical.
FAQ
What is the maximum supported number of phases for LTC3774EUHE#PBF in a synchronized system?
The LTC3774EUHE#PBF supports up to 12-phase operation when multiple units are daisy-chained using the CLKOUT and MODE/PLLIN pins. Each LTC3774EUHE#PBF contributes two phases, and phase alignment between units is controlled via the PHSMD pin voltage. The datasheet confirms that up to six LTC3774EUHE#PBF controllers can be paralleled to achieve 1-, 2-, 3-, 4-, 6-, 8-, or 12-phase configurations with deterministic timing relationships.
Does LTC3774EUHE#PBF support startup into a pre-biased output?
Yes, the LTC3774EUHE#PBF supports smooth startup into pre-biased outputs. During initial power-up, the bottom MOSFET is disabled until the soft-start voltage (from TK/SS or internal ramp) exceeds the sensed VOSNS+ level, preventing reverse current flow and output discharge. This behavior is explicitly documented in the "Shutdown and Start-Up" section of the LTC3774EUHE#PBF datasheet and verified in typical application circuits.
How is DCR temperature compensation implemented on LTC3774EUHE#PBF?
The LTC3774EUHE#PBF implements DCR temperature compensation via ITEMP1 and ITEMP2 pins, each accepting a voltage from an external NTC thermistor placed near its associated output inductor. The internal circuitry adjusts the current sense gain based on this voltage to counteract DCR drift with temperature. When floating, compensation is disabled - a feature confirmed in the PIN FUNCTIONS section and Electrical Characteristics table (ITEMP parameter).
What are the absolute maximum ratings for VIN and INTVCC on LTC3774EUHE#PBF?
The absolute maximum rating for VIN on the LTC3774EUHE#PBF is –0.3V to 40V, and for INTVCC it is –0.3V to 6V. These values are specified in the Absolute Maximum Ratings table of the official datasheet. Exceeding these limits may cause permanent damage. The recommended operating range remains 4.5V–38V for VIN and 5.3V–5.7V for INTVCC under normal conditions.
Can LTC3774EUHE#PBF operate with a 0.2mΩ DCR inductor?
Yes, the LTC3774EUHE#PBF is specifically designed to operate with inductors as low as 0.2mΩ DCR, enabled by its dual-path current sensing architecture (SNSA+/SNSD+) and proprietary SNR enhancement technique. The datasheet states: "The LTC3774 can sense a DCR value as low as 0.2mΩ with careful PCB layout," and typical application circuits validate operation with 0.32mΩ DCR inductors.
LTC3774EUHE#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- PolyPhase®
- Package/Case:
- 36-WFQFN Exposed Pad
- Packaging:
- Tube
- Product Status:
- Active
- Output Type:
- PWM Signal
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Number of Outputs:
- 2
- Output Phases:
- 2
- Voltage - Supply (Vcc/Vdd):
- 4.5V ~ 38V
- Frequency - Switching:
- 150kHz ~ 1.2MHz
- Duty Cycle (Max):
- 98%
- Synchronous Rectifier:
- No
- Clock Sync:
- No
- Serial Interfaces:
- -
- Control Features:
- Current Limit, Enable, Frequency Control, Power Good, Soft Start, Tracking
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 36-QFN (5x6)
LTC3774EUHE#PBF FAQ
1.How can I place an order for LTC3774EUHE#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC3774EUHE#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 LTC3774EUHE#PBF reliable?
The price and inventory of LTC3774EUHE#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC3774EUHE#PBF is usually 5 days.
3.What payment methods are accepted for LTC3774EUHE#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC3774EUHE#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC3774EUHE#PBF?
LTC3774EUHE#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC3774EUHE#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 LTC3774EUHE#PBF?
For technical support, including LTC3774EUHE#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC3774EUHE#PBF requirements.
6.How does Aetrix verify that LTC3774EUHE#PBF is sourced from the original manufacturer or authorized distributors?
All LTC3774EUHE#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 LTC3774EUHE#PBF meets industry standards.
7.What is the process for return or replacement of LTC3774EUHE#PBF?
All LTC3774EUHE#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC3774EUHE#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 LTC3774EUHE#PBF part is unused and in its original packaging.
Return procedure for LTC3774EUHE#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC3774EUHE#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…
