My Inquiry
My Account
Analog Devices Inc. LTC3850EUF#TRPBF
- Part No.:
- LTC3850EUF#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- DC DC Switching Controllers
- Package:
- 28-WFQFN Exposed Pad
- Datasheet:
-
LTC3850EUF#TRPBF.pdf
- Description:
- IC REG CTRLR BUCK 28QFN
- Quantity:
- Payment:
- Shipping:
Inventory:3,732
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC3850EUF#TRPBF from Analog Devices is a dual, 2-phase synchronous step-down switching controller driving all-N-channel MOSFET stages. It delivers up to 95% efficiency, supports 250kHz–780kHz phase-lockable fixed-frequency operation, and features ±1% 0.8V reference accuracy. It enables high-efficiency power conversion in compact DC/DC systems such as notebook computers and portable instrumentation.
For engineers reviewing the LTC3850EUF#TRPBF datasheet, LTC3850EUF#TRPBF pinout, LTC3850EUF#TRPBF application, or LTC3850EUF#TRPBF equivalent, key selection criteria include dual-phase current-mode control, independent soft-start/tracking (TK/SS), RSENSE/DCR sensing flexibility, and automotive-grade AEC-Q100 qualification for LTC3850I variants.
Technical Context
The LTC3850EUF#TRPBF implements constant-frequency current-mode control with two independent 180° out-of-phase channels, minimizing input ripple and supply noise. Each channel uses an error amplifier with OPTI-LOOP® compensation and a precision 0.8V reference, enabling stable regulation across wide output capacitance and ESR ranges.
It supports three light-load operating modes-Burst Mode®, pulse-skipping, and forced continuous conduction-selected via the MODE/PLLIN pin. The FREQ/PLLFLTR pin sets oscillator frequency from 250kHz to 780kHz, and the IC can be synchronized to an external clock or operate in PLL mode for noise-sensitive applications.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Topology | Dual synchronous buck controller - drives two independent N-channel MOSFET half-bridges with 180° phase shift to reduce input capacitor stress. |
| Input Voltage Range | 4V to 24V (28V absolute max) - supports common battery chemistries and intermediate bus voltages without external regulators. |
| Output Voltage Accuracy | ±1% at 0.8V reference - ensures tight regulation of downstream 1.8V, 2.5V, 3.3V rails under line/load/temperature variation. |
| Switching Frequency | 250kHz to 780kHz, phase-lockable - adjustable via FREQ/PLLFLTR voltage; enables optimization of efficiency vs. size trade-offs. |
| Current Sensing | RSENSE or DCR - selectable via ILIM pin configuration (GND/FLOAT/INTVCC), supporting flexible layout and loss minimization. |
| Soft-Start & Tracking | Independent TK/SS1/TK/SS2 pins - enable programmable ramp rate or precise voltage tracking between outputs during startup. |
| Power Good Output | Open-drain PGOOD with ±7.5% trip window and 17µs mask timer - provides reliable system-level power sequencing and fault indication. |
Pinout & Package
The LTC3850EUF#TRPBF is housed in a 28-lead (4mm × 4mm) plastic QFN package with exposed pad (Pin 29) soldered to PCB for thermal and signal grounding. Pin count and layout match the UF package variant per Analog Devices' Rev. D datasheet.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| RUN1, RUN2 | Channel enable inputs | Independent shutdown control: ≥1.22V enables; <1.1V disables; internal 0.5µA pull-up allows logic-level or RC-controlled sequencing. |
| TK/SS1, TK/SS2 | Soft-start/tracking inputs | Internal 1.3µA current charges external capacitor to ramp VOUT linearly; also accepts resistor-divided master rail for tracking. |
| SENSE1+/SENSE1−, SENSE2+/SENSE2− | Current sense differential inputs | Accepts RSENSE or DCR network signals; bias current ±2µA enables low-loss sensing with minimal offset impact. |
| VFB1, VFB2 | Error amplifier feedback inputs | Compare remote output voltage (via resistive divider) against 0.8V reference; ±50nA input current minimizes divider error. |
| ITH1, ITH2 | Error amplifier output / current threshold | Directly sets peak inductor current; gm = 2.2 mmho enables stable loop compensation across wide COUT/ESR range. |
| TG1, TG2 / BG1, BG2 | Top/bottom gate drivers | Drive N-MOSFET gates with 2.6Ω/1.5Ω pull-up/pull-down; 25ns transition time supports high-frequency, low-loss switching. |
| BOOST1, BOOST2 | Floating bootstrap supplies | Provide gate drive above SW node; swing from ~INTVCC–0.7V to VIN+INTVCC, enabling full N-MOSFET utilization in buck topology. |
| PGOOD | Power good indicator | Open-drain output pulled low when either VOUT deviates >±7.5% from setpoint after 17µs debounce - critical for system reset coordination. |
Key Features
| Feature | Design Value |
|---|---|
| OPTI-LOOP® compensation | Enables stable loop response across diverse output capacitors (ceramic, polymer, electrolytic) and ESR values without redesigning compensation network. |
| Independent channel control | Separate RUN, TK/SS, and ITH pins per channel allow asymmetric start-up timing, independent enable/disable, and tailored transient response. |
| Three selectable light-load modes | Burst Mode® (highest efficiency), pulse-skipping (low ripple/audio noise), or forced CCM (lowest ripple) - selected via MODE/PLLIN pin state. |
| Pre-biased output support | Allows safe startup into pre-charged output capacitors without reverse current flow - essential for hot-swap and multi-rail sequencing. |
| AEC-Q100 qualified variants | LTC3850I versions meet automotive reliability requirements (–40°C to +85°C), including HTOL, temperature cycling, and ESD testing. |
Applications
| High-Efficiency Notebook Power | Portable Instrumentation Supply |
|---|---|
|
Use Scenario: Dual-rail (3.3V/2.5V or 1.8V/1.2V) power delivery in space-constrained notebooks with thermal limits. IC Role / Device Role / Timing Role: Dual-phase synchronous buck controller managing independent CPU/core and I/O rails with 180° interleaving. Use Value: Reduces input RMS current by ~30% versus single-phase, lowering input capacitor count and board area while maintaining <1% output regulation. |
Use Scenario: Battery-powered handheld test equipment requiring long runtime and low-noise analog supply rails. IC Role / Device Role / Timing Role: High-accuracy, low-quiescent-current dual controller generating clean 3.3V and 1.8V rails from Li-ion input. Use Value: Burst Mode® operation achieves <30µA total quiescent current at light load, extending battery life without sacrificing transient response. |
| DC Power Distribution System | Industrial Embedded Control |
|
Use Scenario: Centralized 12V-to-5V/3.3V conversion feeding multiple distributed loads in telecom or server backplanes. IC Role / Device Role / Timing Role: Dual-channel controller with phase synchronization minimizing conducted EMI on shared input bus. Use Value: Phase-lockable 780kHz operation enables deterministic EMI filtering and reduces input filter size by 40% vs. 300kHz designs. |
Use Scenario: Ruggedized PLC or motor drive module needing reliable, field-serviceable power for FPGA, MCU, and analog front-end. IC Role / Device Role / Timing Role: Industrial-grade dual controller with wide VIN (4V–24V), robust UVLO (3V), and -40°C to +85°C operation. Use Value: Independent RUN/TK/SS pins enable firmware-controlled rail sequencing and graceful shutdown during brownout events. |
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 |
|---|---|---|---|
| MP2918GL-Z | Single-chip dual-phase controller with integrated MOSFET drivers only; no external gate driver flexibility; fixed 500kHz frequency. | Lacks RSENSE/DCR selectability and independent TK/SS pins; not suitable for pre-biased or asymmetric tracking designs. | Choose MP2918GL-Z only if board space is critical and design requires monolithic integration over flexibility. |
| LTC3838EUFD#TRPBF | Pin-compatible dual-phase controller with identical pinout and feature set but wider 4.5V–38V input range and higher 1MHz max frequency. | Supports higher-input industrial buses (24V/36V); same soft-start, mode selection, and compensation architecture as LTC3850EUF#TRPBF. | Select LTC3838EUFD#TRPBF when input exceeds 24V or 1MHz operation is required; otherwise, LTC3850EUF#TRPBF remains optimal for 4V–24V systems. |
Compared with MP2918GL-Z, LTC3850EUF#TRPBF offers superior design flexibility via external MOSFET drive and configurable sensing, while LTC3838EUFD#TRPBF extends input range and frequency headroom - both alternatives require layout review due to differing thermal and routing constraints.
Availability
LTC3850EUF#TRPBF is available at Aetrix Electronics and suitable for notebook computers, portable instrumentation, and DC power distribution systems requiring stable component supply, long-term lifecycle support, and AEC-Q100-compliant variants for automotive-adjacent deployments.
Supply support for LTC3850EUF#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. is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving industrial, communications, automotive, and consumer markets since 1965.
The LTC3850 series belongs to Analog Devices' Power by Linear™ portfolio, designed specifically for high-efficiency, high-density DC/DC conversion in space- and thermal-constrained applications where precision regulation and flexible sequencing are critical.
FAQ
What is the maximum supported switching frequency for LTC3850EUF#TRPBF?
The LTC3850EUF#TRPBF supports a phase-lockable switching frequency range of 250kHz to 780kHz, set via the FREQ/PLLFLTR pin voltage. At VFREQ ≥ 2.4V, the nominal frequency reaches 780kHz (typical), enabling compact magnetics while maintaining high efficiency in 12V-input systems.
Does LTC3850EUF#TRPBF support pre-biased output startup?
Yes, LTC3850EUF#TRPBF supports pre-biased output startup. Its current-mode architecture and reverse-current comparator (IREV) prevent negative inductor current flow during startup, allowing safe operation into pre-charged output capacitors without damaging external components or causing voltage overshoot.
How does the ILIM pin configure current-sense thresholds on LTC3850EUF#TRPBF?
On LTC3850EUF#TRPBF, the ILIM pin selects maximum current-sense threshold per channel: tied to SGND → 20mV (typ), FLOAT → 40mV (typ), or INTVCC → 60mV (typ). This enables optimization of current-limit accuracy and MOSFET SOA across varying RSENSE values and load conditions.
Can LTC3850EUF#TRPBF synchronize to an external clock?
Yes, LTC3850EUF#TRPBF can synchronize to an external clock via the MODE/PLLIN pin. When driven with a clean square wave within 250kHz–780kHz, the internal PLL locks to the external source, eliminating beat frequencies and enabling deterministic EMI reduction in multi-controller systems.
What package type and thermal performance does LTC3850EUF#TRPBF use?
LTC3850EUF#TRPBF uses a 28-lead 4mm × 4mm plastic QFN package with exposed thermal pad (Pin 29). Its θJA is 37°C/W, enabling >5A per channel operation at ambient temperatures up to +85°C with standard 2-layer PCB copper pours and thermal vias under the exposed pad.
LTC3850EUF#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 28-WFQFN Exposed Pad
- 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):
- 4V ~ 24V
- Frequency - Switching:
- 250kHz ~ 780kHz
- Duty Cycle (Max):
- 97.2%
- Synchronous Rectifier:
- Yes
- Clock Sync:
- No
- Serial Interfaces:
- -
- Control Features:
- Current Limit, Enable, Frequency Control, Power Good, Soft Start, Tracking
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 28-QFN (4x4)
LTC3850EUF#TRPBF FAQ
1.How can I place an order for LTC3850EUF#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC3850EUF#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 LTC3850EUF#TRPBF reliable?
The price and inventory of LTC3850EUF#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC3850EUF#TRPBF is usually 5 days.
3.What payment methods are accepted for LTC3850EUF#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC3850EUF#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC3850EUF#TRPBF?
LTC3850EUF#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC3850EUF#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 LTC3850EUF#TRPBF?
For technical support, including LTC3850EUF#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC3850EUF#TRPBF requirements.
6.How does Aetrix verify that LTC3850EUF#TRPBF is sourced from the original manufacturer or authorized distributors?
All LTC3850EUF#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 LTC3850EUF#TRPBF meets industry standards.
7.What is the process for return or replacement of LTC3850EUF#TRPBF?
All LTC3850EUF#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC3850EUF#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 LTC3850EUF#TRPBF part is unused and in its original packaging.
Return procedure for LTC3850EUF#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC3850EUF#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…
