My Inquiry
My Account
Analog Devices Inc. LTC7803IUD#PBF
- Part No.:
- LTC7803IUD#PBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- DC DC Switching Controllers
- Package:
- 16-WFQFN Exposed Pad
- Datasheet:
-
LTC7803IUD#PBF.pdf
- Description:
- LOW IQ SYNCHRONOUS BUCK CONTROLL
- Quantity:
- Payment:
- Shipping:
Inventory:227
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC7803IUD#PBF from Analog Devices is a high-performance, 100% duty cycle capable, synchronous step-down DC/DC controller driving all-N-channel MOSFET stages. It operates from 4.5V to 40V input, delivers up to 40V output, and features 12µA no-load quiescent current, spread spectrum EMI reduction, and programmable 100kHz–3MHz switching frequency - enabling compact, efficient power supplies in automotive infotainment and industrial motor control systems.
For engineers reviewing the LTC7803IUD#PBF datasheet, LTC7803IUD#PBF pinout, LTC7803IUD#PBF application, or LTC7803IUD#PBF equivalent, key selection considerations include its RSENSE/DCR current sensing flexibility, OPTI-LOOP compensation for wide output capacitor/ESR tolerance, PassThru™ 100% duty cycle capability, AEC-Q100 qualification, and thermally enhanced 3mm × 3mm QFN package with exposed GND pad.
Technical Context
The LTC7803IUD#PBF implements a constant-frequency peak current mode architecture with phase-lockable oscillator (0.1–3MHz), enabling precise timing synchronization and predictable transient response. Its dual-mode gate drivers (TG/BG) support fast 15ns turn-on/off delays and 3Ω/1.5Ω on-resistance, optimized for high-efficiency synchronous rectification across wide VIN–VOUT differentials.
It integrates independent INTVCC and EXTVCC LDOs with 4.7V switchover threshold, allowing external biasing to reduce input-referred quiescent current; combined with MODE-selectable light-load operation (Burst, pulse-skipping, or forced continuous), it achieves 12µA IQ at 14VIN→3.3VOUT and 1.2µA shutdown current.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 4.5V to 40V - supports wide-input industrial and automotive battery rails without pre-regulation. |
| No-Load Quiescent Current | 12µA at 14VIN→3.3VOUT - extends runtime in always-on battery-powered systems. |
| Switching Frequency Range | 100kHz to 3MHz (programmable via FREQ pin resistor) - enables optimization of size vs. efficiency in space-constrained designs. |
| Feedback Reference Voltage | 0.792V to 0.808V (±1.5% over temp) - ensures tight output regulation across –40°C to 125°C junction range. |
| Current Sense Threshold | 45mV to 55mV max - allows accurate current limiting with low-value, low-power sense resistors or DCR sensing. |
| 100% Duty Cycle Capability | PassThru™ mode enabled - maintains regulation during VIN-to-VOUT dropout, critical for automotive cold-crank scenarios. |
| Spread Spectrum Range | ±10% frequency dither (PLLIN/SPREAD = INTVCC) - reduces peak conducted/radiated EMI by >10dB, easing CISPR 25 Class 5 compliance. |
Pinout & Package
Package: 16-pin (3mm × 3mm) plastic QFN with exposed thermal pad (Pin 17 = GND). Requires soldering of exposed pad to PCB for θJC = 4.2°C/W thermal performance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| TG (Pin 1) | Top N-MOSFET Gate Driver Output | Floating driver with INTVCC-referenced swing; supports 100% duty cycle via internal charge pump. |
| SW (Pin 2) | Switch Node Connection | Connects to inductor and BOOST capacitor; voltage swings from GND to VIN during operation. |
| TRACK/SS (Pin 3) | Soft-Start & Tracking Input | Internal 12.5µA pull-up sets soft-start ramp time (0.65ms/10nF); enables output voltage tracking of other supplies. |
| SENSE+ (Pin 4) | Current Sense Positive Input | Differential input to current comparator; used with SENSE– to set ITRIP based on RSENSE or DCR. |
| INTVCC (Pin 12) | Internal 5.15V LDO Output | Powers gate drivers and control circuitry; requires ≥4.7µF ceramic decoupling to GND. |
| MODE (Pin 11) | Light-Load Operation Mode Select | GND = Burst Mode; INTVCC = forced continuous; INTVCC via 100kΩ = pulse-skipping - selectable per system efficiency needs. |
| PLLIN/SPREAD (Pin 10) | Synchronization & Spread Spectrum Control | External clock input for phase-locking; tied to INTVCC enables spread spectrum; tied to GND disables dither. |
| GND (Pin 17) | Power & Signal Ground | Exposed thermal pad must be soldered to PCB ground plane for thermal and EMI performance. |
Key Features
| Feature | Design Value |
|---|---|
| OPTI-LOOP Compensation | Enables stable loop response across wide range of output capacitor values (10µF–1000µF) and ESR (0.5mΩ–100mΩ), reducing design iteration. |
| AEC-Q100 Qualified | Rated for –40°C to +125°C junction temperature - validated for automotive powertrain and ADAS subsystems. |
| RSENSE or DCR Sensing | Flexible current sensing eliminates need for dedicated sense resistors in cost-sensitive or high-current applications. |
| Low Shutdown IQ | 1.2µA shutdown current - preserves battery life in systems requiring deep sleep states. |
| Thermally Enhanced QFN | 3mm × 3mm footprint with exposed GND pad achieves θJA = 68°C/W - enables high-power density without heatsinks. |
Applications
| Automotive Infotainment Power | Industrial PLC I/O Module Supply |
|---|---|
Use Scenario: Powering 3.3V/5V logic and display interfaces in head units under 9V–16V battery input with cold-crank down to 4.5V. IC Role / Device Role / Timing Role: Primary synchronous buck controller managing 20A load with PassThru™ mode maintaining regulation during cranking. Use Value: 12µA no-load IQ extends standby time; spread spectrum meets CISPR 25 Class 5 radiated emissions limits without added filtering. |
Use Scenario: Generating isolated 12V/24V auxiliary rails from 24V/48V factory bus in programmable logic controllers. IC Role / Device Role / Timing Role: High-voltage step-down controller driving discrete N-MOSFETs with RSENSE sensing for precise current limiting. Use Value: 40V max input withstands 48V bus transients; OPTI-LOOP compensates for wide-range bulk capacitor aging in harsh environments. |
| Military Avionics DC-DC Stage | Telecom Base Station Bias Supply |
Use Scenario: Providing 5V/3.3V bias for FPGA and ADCs in airborne radar modules operating from 28V aircraft bus. IC Role / Device Role / Timing Role: Phase-lockable controller synchronized to system clock to avoid beat frequencies in sensitive RF sections. Use Value: 3MHz max frequency enables ultra-small magnetics; AEC-Q100 qualification supports DO-160 environmental compliance. |
Use Scenario: Generating 12V intermediate rail from 48V telecom rectifier output for downstream POL converters in macro base stations. IC Role / Device Role / Timing Role: High-efficiency primary controller with EXTVCC biasing to reduce input-referred losses from 48V source. Use Value: EXTVCC switchover lowers total system IQ; 100% duty cycle handles brownout events during grid instability. |
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 |
|---|---|---|---|
| MP2918GL-Z | Fixed 500kHz frequency; no spread spectrum; 2.5µA IQ; supports only RSENSE sensing. | Lacks PassThru™ mode and AEC-Q100 rating; limited to non-automotive industrial use. | Lower-cost option where EMI and dropout margin are not critical. |
| TPS53632GRTAR | Integrated MOSFET drivers only (no external FET control); 3.3V–20V input; 12A max; no 100% duty cycle. | Not suitable for >20V input or 100% duty cycle requirements; targets mid-power integrated solutions. | Preferred when board space is constrained and discrete FETs are unnecessary. |
Compared with MP2918GL-Z and TPS53632GRTAR, the LTC7803IUD#PBF uniquely combines 40V input, 100% duty cycle, spread spectrum, and AEC-Q100 qualification - making it the only choice for automotive and high-reliability industrial buck controllers requiring both wide VIN and EMI robustness.
Availability
LTC7803IUD#PBF is available at Aetrix Electronics and suitable for automotive infotainment, industrial PLC power, military avionics, and telecom base station applications requiring stable component supply, long-term lifecycle support, and AEC-Q100-compliant sourcing.
Supply support for LTC7803IUD#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 is a global leader in high-performance analog, mixed-signal, and digital signal processing semiconductors, serving precision instrumentation, industrial automation, communications, and automotive markets.
The LTC7803 belongs to Analog Devices' Power by Linear™ controller family, designed specifically for high-efficiency, high-reliability DC/DC conversion in demanding automotive, industrial, and aerospace applications where wide input range, low IQ, and EMI control are essential.
FAQ
What is the maximum input voltage supported by the LTC7803IUD#PBF?
The LTC7803IUD#PBF supports an absolute maximum input voltage of 40V on the VIN pin, with guaranteed operation from 4.5V to 40V. This wide range enables direct connection to 24V and 36V industrial buses and 12V/24V automotive systems including cold-crank conditions down to 4.5V. Exceeding 40V may cause permanent damage per Absolute Maximum Ratings.
Does the LTC7803IUD#PBF support 100% duty cycle operation, and how is it enabled?
Yes, the LTC7803IUD#PBF supports true 100% duty cycle operation via its PassThru™ feature. When the input voltage approaches the regulated output voltage, the controller automatically extends the top MOSFET on-time to maintain regulation without dropout. No external components or configuration are required - it is inherent to the architecture and active whenever needed.
How does spread spectrum operation reduce EMI in the LTC7803IUD#PBF?
The LTC7803IUD#PBF reduces peak conducted and radiated EMI by ±10% frequency dither when PLLIN/SPREAD is tied to INTVCC. This spreads energy across a wider bandwidth, lowering spectral peaks by up to 10dB - significantly easing compliance with CISPR 25 Class 5 and FCC Part 15 standards without adding ferrite beads or shielding.
What is the purpose of the EXTVCC pin on the LTC7803IUD#PBF, and when should it be used?
The EXTVCC pin on the LTC7803IUD#PBF provides an alternative bias path for the INTVCC LDO. When driven above 4.7V, it disables the VIN-based LDO and powers INTVCC from the external source - reducing input-referred quiescent current and improving overall system efficiency. It is recommended when a clean, efficient auxiliary rail (e.g., 5V or 12V) is available.
Can the LTC7803IUD#PBF be synchronized to an external clock, and what is the valid frequency range?
Yes, the LTC7803IUD#PBF can be synchronized to an external clock applied to the PLLIN/SPREAD pin. The valid synchronizable frequency range is 0.1MHz to 3MHz, matching its internal VCO range. During synchronization, the controller locks the rising edge of TG to the external clock's rising edge, eliminating beat frequencies in multi-rail systems.
LTC7803IUD#PBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 16-WFQFN 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 ~ 40V
- Frequency - Switching:
- 100kHz ~ 3MHz
- Duty Cycle (Max):
- 100%
- Synchronous Rectifier:
- Yes
- Clock Sync:
- Yes
- Serial Interfaces:
- -
- Control Features:
- Enable, Frequency Control, Phase Control
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-QFN (3x3)
LTC7803IUD#PBF FAQ
1.How can I place an order for LTC7803IUD#PBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC7803IUD#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 LTC7803IUD#PBF reliable?
The price and inventory of LTC7803IUD#PBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC7803IUD#PBF is usually 5 days.
3.What payment methods are accepted for LTC7803IUD#PBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC7803IUD#PBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC7803IUD#PBF?
LTC7803IUD#PBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC7803IUD#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 LTC7803IUD#PBF?
For technical support, including LTC7803IUD#PBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC7803IUD#PBF requirements.
6.How does Aetrix verify that LTC7803IUD#PBF is sourced from the original manufacturer or authorized distributors?
All LTC7803IUD#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 LTC7803IUD#PBF meets industry standards.
7.What is the process for return or replacement of LTC7803IUD#PBF?
All LTC7803IUD#PBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC7803IUD#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 LTC7803IUD#PBF part is unused and in its original packaging.
Return procedure for LTC7803IUD#PBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC7803IUD#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…
