My Inquiry
My Account
Analog Devices Inc. LTC3811EG#TRPBF
- Part No.:
- LTC3811EG#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- DC DC Switching Controllers
- Package:
- 36-SSOP (0.209", 5.30mm Width)
- Datasheet:
-
LTC3811EG#TRPBF.pdf
- Description:
- IC REG CTRLR BUCK 36SSOP
- Quantity:
- Payment:
- Shipping:
Inventory:3,972
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC3811EG#TRPBF from Analog Devices (formerly Linear Technology) is a dual-output, multiphase synchronous step-down DC/DC controller optimized for low-voltage outputs up to 3.3V in high-current applications such as ASIC core and I/O supplies. It supports 2-, 3-, 4-, 6-, or 12-phase operation via MODE/SYNC, CLKOUT, and PHASEMODE; features ±0.5% output voltage accuracy over temperature; programmable current sense threshold (24mV–85mV); and operates from 4.5V to 30V input with 250kHz–750kHz adjustable switching frequency.
For engineers reviewing the LTC3811EG#TRPBF datasheet, LTC3811EG#TRPBF pinout, LTC3811EG#TRPBF application, or LTC3811EG#TRPBF equivalent, this page delivers verified technical context on PolyPhase® control architecture, differential remote sensing, voltage positioning, phase-programmable operation, and QFN-38 package integration-critical for high-density server and telecom power designs requiring tight regulation and load sharing.
Technical Context
The LTC3811EG#TRPBF implements fixed-frequency peak current mode control with two independent high-bandwidth error amplifiers and a dedicated high-speed differential remote sense amplifier (gain = 1.000 V/V, offset ≤ ±6 mV). Its PLL-based synchronization accepts external clocks from 175kHz to 900kHz, and internal oscillator frequency is set via PLL/LPF pin voltage (250kHz–750kHz).
Multiphase coordination is enabled through CLKOUT daisy-chaining and PHASEMODE pin voltage selection (0V → 180°, 50% INTVCC → 180°, INTVCC → 120° channel-to-channel phase), while voltage positioning (via CSOUT) provides programmable droop using external resistor networks-only available in the QFN package variant.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 4.5V to 30V - supports wide industrial and telecom input rails without pre-regulation |
| Output Accuracy | ±0.5% over –40°C to +85°C - ensures stable core/I/O voltage under thermal stress |
| Current Sense Range | 24mV to 85mV - enables precise DCR or discrete resistor sensing with minimal power loss |
| Min On-Time | 65ns typical - supports high VIN-to-low VOUT conversion (e.g., 12V→1.2V) at high frequency |
| Gate Driver Strength | 1.0A peak source/sink per TG/BG - drives multiple paralleled MOSFETs in high-current phases |
| Differential Sense Gain | 0.995–1.005 V/V - maintains <0.5% gain error for accurate remote voltage regulation |
| Shutdown Current | 20μA - enables ultra-low-power system standby modes |
Pinout & Package
The LTC3811EG#TRPBF is housed in a 36-lead plastic SSOP wide (G package), 10.2mm × 5.3mm, with exposed pad not present (QFN variant has exposed PGND pad; SSOP does not). Pin count and function mapping match the LTC3811EG series specification.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| FB1, FB2 | Error amplifier feedback inputs | Reference point for output voltage regulation; connected to resistor divider or differential amp output |
| SENSE1+, SENSE1− SENSE2+, SENSE2− | Current sense differential inputs | Accept DCR or Rsense signals; common-mode range 0V–3.5V supports low-side sensing |
| TG1, TG2 BG1, BG2 | Top/bottom gate drivers | Drive N-channel MOSFETs; 1.0A peak current minimizes dead-time losses in high-frequency operation |
| CLKOUT | Multiphase clock output | Enables daisy-chain synchronization of up to 12 phases across multiple LTC3811 controllers |
| PHASEMODE | Phase relationship control | Voltage-selectable 180° or 120° inter-channel phase-only functional in QFN; SSOP (LTC3811EG) fixes at 180° |
| RUN1, RUN2 | Independent enable inputs | Allow staggered startup or fault isolation per channel; TTL-compatible thresholds (0.3V/1.8V) |
| PGOOD1, PGOOD2 | Open-drain power-good indicators | Assert low when FB deviates >±10%; includes 145μs fault delay and 38μs recovery filter |
Key Features
| Feature | Design Value |
|---|---|
| Dual independent controllers | Enables ratiometric or sequenced tracking of core and I/O rails with separate soft-start and RUN control |
| Programmable current sense threshold | 24mV–85mV range allows optimization for DCR sensing (low loss) or precision shunt (high accuracy) |
| High-speed differential remote sense | 8MHz unity-gain bandwidth and 100dB PSRR reject PCB noise, enabling stable regulation at point-of-load |
| PLL synchronization | Locks to external clocks from 175kHz–900kHz-eliminates beat frequencies in multi-rail systems |
| Select CCM/DCM operation | MODE/SYNC pin selects forced continuous conduction (low ripple) or pulse-skipping (light-load efficiency) |
Applications
| Network Server Power | High-Current ASIC Supply |
|---|---|
Use Scenario: Dual 2-phase buck supplying CPU core (1.2V/100A) and I/O (1.8V/40A) in 1U rack server with strict thermal and transient response requirements. IC Role / Device Role / Timing Role: LTC3811EG#TRPBF acts as master dual-phase controller coordinating gate timing, current sharing, and voltage positioning across parallel phases. Use Value: 65ns min on-time and 1.0A gate drive support high-frequency, low-duty-cycle operation essential for 12V→1.2V conversion at >500kHz. | Use Scenario: Single-output 4-phase regulator powering FPGA core rail with dynamic load steps up to 50A/μs and <1% output deviation. IC Role / Device Role / Timing Role: LTC3811EG#TRPBF configures as single-output multiphase controller using CLKOUT daisy-chain and PHASEMODE-equivalent fixed 180° interleaving (SSOP package). Use Value: ±0.5% output accuracy and 8MHz error amplifier bandwidth ensure tight regulation during fast load transients. |
| Low-Voltage Power Distribution | Telecom Base Station RF Power |
Use Scenario: Distributed 3.3V/30A supply feeding multiple DSPs and ADCs across a large PCB with >15cm trace length between converter and loads. IC Role / Device Role / Timing Role: LTC3811EG#TRPBF uses differential remote sensing (DIFF/IN+/−) to compensate for IR drop across long PCB traces. Use Value: High-PSRR (100dB) differential amplifier rejects board noise, maintaining <±2mV sense error at full load. | Use Scenario: Dual-output supply generating 2.5V/20A RF PA bias and 1.1V/35A digital logic rail in macrocell base station with strict EMI and thermal constraints. IC Role / Device Role / Timing Role: LTC3811EG#TRPBF implements independent soft-start and sequencing (SS/TRACK1/2) to prevent inrush current and ensure safe power-up order. Use Value: Programmable soft-start capacitor charging current (2.5μA) enables precise ramp rate control without external circuitry. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-output multiphase controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LTC3870IUFD#TRPBF | Single-channel, 6-phase capable; supports 0.6V reference; no PHASEMODE pin; requires external clock generator for multiphase sync | Best for space-constrained single-rail high-phase-count designs; lacks dual independent outputs | Select when only one regulated rail is needed and higher phase count (>4) is required |
| MP2940AGQSE-LF-Z | Fixed 600kHz frequency; integrated MOSFET drivers only (no external FET control); no differential remote sense; 1.5% FB accuracy | Suitable for cost-sensitive, lower-precision mid-power applications; no voltage positioning or DCR sensing | Select for simplified BOM and lower design complexity where ±1.5% accuracy suffices |
Compared with LTC3811EG#TRPBF, LTC3870IUFD#TRPBF trades dual independent control for higher phase scalability but loses tracking/sequencing flexibility, while MP2940AGQSE-LF-Z sacrifices precision, sensing flexibility, and programmability for integration and cost-making LTC3811EG#TRPBF optimal for high-accuracy, multi-rail telecom and server power.
Availability
LTC3811EG#TRPBF is available at Aetrix Electronics and suitable for network servers, high-current ASIC supplies, and low-voltage power distribution systems requiring stable component supply, long-term lifecycle support, and guaranteed parametric performance across –40°C to +85°C.
Supply support for LTC3811EG#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 acquired Linear Technology in 2017 and maintains its high-performance power management portfolio with rigorous automotive- and industrial-grade qualification.
The LTC3811EG#TRPBF belongs to Linear's PolyPhase® controller family, engineered specifically for high-efficiency, high-current, low-voltage DC/DC conversion in datacenter, networking, and telecom infrastructure where phase interleaving, remote sensing, and tight regulation are mandatory.
FAQ
What is the operating temperature range for the LTC3811EG#TRPBF?
The LTC3811EG#TRPBF is rated for operation from –40°C to +85°C ambient temperature. This range is validated per the device's electrical characteristics table and thermal shutdown specification (TJSD = 165°C with 25°C hysteresis), ensuring reliable performance in industrial and telecom environments where ambient temperatures fluctuate significantly. The SSOP package's θJA = 100°C/W reflects its thermal design for standard PCB layouts.
Does the LTC3811EG#TRPBF support differential remote sensing?
Yes, the LTC3811EG#TRPBF supports differential remote sensing via dedicated DIFF/IN+ and DIFF/IN– pins with a precision gain of 1.000 V/V (±0.5%) and 8MHz bandwidth. The DIFF/OUT pin provides buffered output for connection to FB pins, enabling accurate point-of-load regulation by compensating for PCB trace IR drop-critical for high-current, low-voltage rails like 1.2V CPU cores.
Can the LTC3811EG#TRPBF be used in single-output multiphase configurations?
Yes, the LTC3811EG#TRPBF can be configured for single-output multiphase operation by connecting FB2 to INTVCC to disable the second error amplifier, tying COMP1 and COMP2 together, and using MODE/SYNC and CLKOUT to synchronize phases. Its SSOP package fixes channel-phase at 180°, supporting robust 2- or 4-phase interleaving without PHASEMODE pin dependency.
What is the minimum on-time specification for the LTC3811EG#TRPBF?
The LTC3811EG#TRPBF has a typical minimum on-time of 65ns, specified under VCOMP = 1.25V conditions. This enables high-step-down ratios (e.g., 12V input to 1.2V output) at frequencies up to 750kHz while maintaining stable PWM operation-essential for modern high-current, low-voltage digital loads requiring fast transient response.
Is voltage positioning supported on the LTC3811EG#TRPBF?
No, voltage positioning (via CSOUT pin) is exclusive to the QFN-package variants (e.g., LTC3811EUHF#TRPBF). The LTC3811EG#TRPBF uses the SSOP package, which omits the CSOUT pin and associated transconductance amplifier. Designers requiring programmable load-line droop must select the QFN version or implement external compensation.
LTC3811EG#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- PolyPhase®
- Package/Case:
- 36-SSOP (0.209", 5.30mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Output Type:
- Transistor Driver
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Number of Outputs:
- 2
- Output Phases:
- 2
- Voltage - Supply (Vcc/Vdd):
- 4.5V ~ 30V
- Frequency - Switching:
- 250kHz ~ 750kHz
- Duty Cycle (Max):
- -
- Synchronous Rectifier:
- Yes
- Clock Sync:
- Yes
- Serial Interfaces:
- -
- Control Features:
- Current Limit, Enable, Phase Control, Power Good, Soft Start, Tracking
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 36-SSOP
LTC3811EG#TRPBF FAQ
1.How can I place an order for LTC3811EG#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC3811EG#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 LTC3811EG#TRPBF reliable?
The price and inventory of LTC3811EG#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC3811EG#TRPBF is usually 5 days.
3.What payment methods are accepted for LTC3811EG#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC3811EG#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC3811EG#TRPBF?
LTC3811EG#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC3811EG#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 LTC3811EG#TRPBF?
For technical support, including LTC3811EG#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC3811EG#TRPBF requirements.
6.How does Aetrix verify that LTC3811EG#TRPBF is sourced from the original manufacturer or authorized distributors?
All LTC3811EG#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 LTC3811EG#TRPBF meets industry standards.
7.What is the process for return or replacement of LTC3811EG#TRPBF?
All LTC3811EG#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC3811EG#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 LTC3811EG#TRPBF part is unused and in its original packaging.
Return procedure for LTC3811EG#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC3811EG#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…
