My Inquiry
My Account
Analog Devices Inc. LTC3809IDD-1#TRPBF
- Part No.:
- LTC3809IDD-1#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- DC DC Switching Controllers
- Package:
- 10-WFDFN Exposed Pad
- Datasheet:
-
LTC3809IDD-1#TRPBF.pdf
- Description:
- IC REG CTRLR BUCK 10DFN
- Quantity:
- Payment:
- Shipping:
Inventory:4,790
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC3809IDD-1#TRPBF from Analog Devices (formerly Linear Technology) is a synchronous step-down DC/DC controller IC that drives external complementary P-channel and N-channel MOSFETs without requiring a current sense resistor. It operates with a fixed 550kHz switching frequency, supports output voltage tracking (coincident or ratiometric), delivers 0.6V ±1.5% reference accuracy, and enables 100% duty cycle for low-dropout operation in battery-powered systems.
For engineers reviewing the LTC3809IDD-1#TRPBF datasheet, LTC3809IDD-1#TRPBF pinout, LTC3809IDD-1#TRPBF application, or LTC3809IDD-1#TRPBF equivalent, key selection considerations include its No RSENSE™ VDS-based current sensing, selectable Burst Mode®/pulse-skipping/forced continuous operation via MODE pin, wide 2.75V–9.8V input range, and thermally enhanced 10-lead 3mm × 3mm DFN package with exposed ground pad.
Technical Context
The LTC3809IDD-1#TRPBF implements a constant-frequency current-mode control architecture using differential VDS sensing across the external P-channel MOSFET to eliminate the need for a discrete sense resistor. Its error amplifier regulates feedback (VFB) against a 0.6V internal reference, while the ITH pin sets peak current threshold and serves as compensation node.
It integrates auxiliary winding regulation via the MODE pin, programmable peak current sense voltage selection (70mV/125mV/204mV) via IPRG pin, and dual protection comparators: overvoltage (0.66V–0.7V at VFB) and short-circuit (60mV/90mV/150mV ΔVSC). The device supports three start-up modes-internal soft-start, external capacitor-programmed soft-start, or output voltage tracking-via the TRACK/SS pin.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Switching Frequency | Fixed 550kHz (±13%) - enables compact magnetics and predictable EMI profile. |
| Input Voltage Range | 2.75V to 9.8V - supports single/dual Li-ion, USB, and intermediate bus rails. |
| Output Voltage Range | 0.6V to VIN - accommodates core logic, I/O, and analog supply domains. |
| Reference Voltage | 0.6V ±1.5% over –40°C to 85°C - ensures tight output regulation accuracy. |
| Quiescent Current | 9μA in shutdown - minimizes battery drain during system sleep states. |
| Peak Gate Drive Current | 1A (TG/BG, <10μs pulse) - supports fast switching of low-RDS(on) MOSFETs. |
| UVLO Threshold | 2.25V (rising), 1.95V (falling) - prevents erratic operation during brownout conditions. |
| Operating Temperature | –40°C to +85°C - qualified for industrial and portable embedded environments. |
Pinout & Package
Package: 10-lead (3mm × 3mm) plastic DFN with exposed thermal pad (Pin 11 = GND). Requires soldering of exposed pad to PCB ground plane for thermal and electrical performance.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| SW (10) | Switch Node | Connects to drain of both external MOSFETs and inductor; serves as negative input to current comparator and reverse-current detector. |
| VIN (9) | Supply Input | Powers internal circuitry and gate drivers; also positive input to differential current comparator (VIN–SW). |
| TG (8) | Top Gate Driver Output | Drives gate of external P-channel MOSFET; swing from PGND to VIN; 1A peak capability. |
| BG (7) | Bottom Gate Driver Output | Drives gate of external N-channel MOSFET; swing from PGND to VIN; 1A peak capability. |
| IPRG (6) | Current Sense Threshold Select | Three-state input (GND/VIN/floating) selects ΔVSENSE(MAX) = 70/204/125mV for P-MOSFET VDS sensing. |
| MODE (1) | Operation Mode Control | Selects Burst Mode® (to VIN), forced continuous (to GND), or pulse-skipping (to VFB); also auxiliary winding feedback input. |
| TRACK/SS (2) | Tracking or Soft-Start Input | Enables output voltage tracking of external rail or external capacitor-programmed soft-start ramp (1μA source). |
| VFB (3) | Feedback Input | Compares divided output voltage against 0.6V reference; input bias current ≤50nA. |
| ITH (4) | Error Amplifier Output / Current Threshold | Sets peak inductor current threshold (0.7V–2V range); also compensation node for loop stability. |
| RUN (5) | Enable Control | Shuts down controller when <1.1V; releases internal 0.7μA pull-up to enable startup. |
Key Features
| Feature | Design Value |
|---|---|
| No RSENSE™ VDS current sensing | Eliminates power loss and board space of external sense resistor; improves efficiency at high currents. |
| Selectably optimized light-load efficiency | Burst Mode® (high efficiency), pulse-skipping (low noise), or forced continuous (lowest ripple) - all configurable via MODE pin. |
| Programmable output voltage tracking | Supports coincident or ratiometric startup sequencing with other rails using external resistor divider on TRACK/SS pin. |
| 100% duty cycle operation | Extends battery runtime by maintaining regulation even as input voltage drops near output level. |
| Integrated fault protection | Dual independent comparators: output overvoltage (0.66V–0.7V at VFB) and short-circuit current limit (60/90/150mV ΔVSC). |
| Micropower shutdown | 9μA quiescent current in shutdown - preserves battery life in always-on portable devices. |
Applications
| Mobile Power Management | Industrial Embedded Systems |
|---|---|
Use Scenario: Regulating core voltage for ARM-based microcontrollers in handheld test equipment powered by dual-cell Li-ion batteries. IC Role / Device Role / Timing Role: Synchronous buck controller managing 1.2V/2A output with precise tracking to I/O rail during cold-start. Use Value: 100% duty cycle maintains regulation down to 1.3V input; No RSENSE™ reduces heat generation in sealed enclosure. |
Use Scenario: Generating stable 3.3V supply for FPGA configuration and communication interfaces in programmable logic controllers. IC Role / Device Role / Timing Role: Primary DC/DC controller with auxiliary winding regulation for isolated auxiliary supplies. Use Value: MODE pin used for secondary-side regulation; 550kHz switching allows small 2.2μH inductor and low-profile layout. |
| Portable Medical Instruments | Distributed DC Power Architectures |
Use Scenario: Powering precision analog front-end (AFE) and low-noise ADC in battery-operated patient monitors. IC Role / Device Role / Timing Role: Low-noise buck controller operating in pulse-skipping mode to avoid audible beat frequencies. Use Value: Pulse-skipping (MODE = VFB) eliminates sub-20kHz switching artifacts while maintaining >85% efficiency at 100mA load. |
Use Scenario: Local point-of-load conversion from 5V/12V intermediate bus to 1.8V for high-speed memory subsystems. IC Role / Device Role / Timing Role: High-efficiency synchronous controller driving low-RDS(on) MOSFETs with minimal external components. Use Value: Wide 2.75V–9.8V input range accommodates bus variations; 0.6V reference enables accurate 1.8V output with ±1% tolerance. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar synchronous buck controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MP2315DJ-LF-Z | Fixed 500kHz frequency; requires external current sense resistor; no output tracking support. | Lacks VDS sensing and TRACK/SS functionality; limited to basic buck conversion without sequencing. | Lower BOM cost where tracking, ultra-low IQ, or No RSENSE™ are not required. |
| TPS54202DDCR | Internal FETs (integrated solution); 4.5V–17V input; no IPRG/MODE flexibility for current threshold or light-load modes. | Not a controller - cannot drive external high-current MOSFETs; unsuitable for >2A or high-efficiency discrete designs. | Preferred only for lower-power (<1.5A), space-constrained designs where integration outweighs efficiency and flexibility needs. |
Compared with MP2315DJ-LF-Z and TPS54202DDCR, the LTC3809IDD-1#TRPBF uniquely combines No RSENSE™ sensing, programmable light-load behavior, output tracking, and wide input range in a thermally robust DFN package - making it optimal for high-efficiency, sequenced, battery-sensitive applications demanding discrete MOSFET control.
Availability
LTC3809IDD-1#TRPBF is available at Aetrix Electronics and suitable for mobile power management, industrial embedded systems, portable medical instruments, and distributed DC power architectures requiring stable component supply, long-term lifecycle support, and traceable sourcing.
Supply support for LTC3809IDD-1#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. (acquired Linear Technology in 2017) is a global leader in high-performance analog, mixed-signal, and power management semiconductors, serving industrial, automotive, communications, and healthcare markets.
The LTC3809 family was designed specifically for high-efficiency, low-input-voltage synchronous buck conversion in portable and battery-powered systems - emphasizing No RSENSE™ operation, flexible light-load modes, and robust sequencing capabilities.
FAQ
What is the function of the IPRG pin on the LTC3809IDD-1#TRPBF?
The IPRG pin on the LTC3809IDD-1#TRPBF selects the maximum peak current sense voltage threshold across the external P-channel MOSFET: 70mV when tied to GND, 204mV when tied to VIN, and 125mV when left floating. This setting directly determines the peak inductor current limit and must be coordinated with the MOSFET's RDS(on) to achieve the target output current. The LTC3809IDD-1#TRPBF uses this pin to adapt current sensing to varying MOSFET characteristics without changing external components.
Does the LTC3809IDD-1#TRPBF support output voltage tracking, and how is it implemented?
Yes, the LTC3809IDD-1#TRPBF supports both coincident and ratiometric output voltage tracking via the TRACK/SS pin. When an external voltage (e.g., from another regulator) is applied through a resistor divider to TRACK/SS, the controller regulates VFB to match that voltage during startup - enabling controlled sequencing. For coincident tracking, the external rail's final value must exceed the LTC3809IDD-1#TRPBF's output, and the resistor ratios must match those of the VFB divider. The LTC3809IDD-1#TRPBF achieves this without additional ICs or complex timing circuits.
How does the MODE pin affect light-load operation of the LTC3809IDD-1#TRPBF?
The MODE pin on the LTC3809IDD-1#TRPBF configures three distinct light-load behaviors: tying to VIN enables Burst Mode® (highest efficiency, audible noise possible), tying to GND enables forced continuous conduction (lowest output ripple, reduced efficiency), and tying to VFB enables pulse-skipping mode (balanced efficiency and noise). During undervoltage (VFB ≤ 0.54V), the LTC3809IDD-1#TRPBF defaults to pulse-skipping regardless of MODE state. This pin also serves as auxiliary winding feedback input for isolated secondary regulation.
What protection features are integrated into the LTC3809IDD-1#TRPBF?
The LTC3809IDD-1#TRPBF integrates overvoltage protection (OVP) that disables the top MOSFET if VFB exceeds 0.66V–0.7V, and short-circuit current limiting that monitors ΔVSC across the bottom N-channel MOSFET (60mV/90mV/150mV depending on IPRG state). It also includes undervoltage lockout (UVLO) with 2.25V turn-on threshold and micropower shutdown (9μA). These protections operate independently and do not require external components - ensuring robust operation in the LTC3809IDD-1#TRPBF without design overhead.
Can the LTC3809IDD-1#TRPBF operate with input voltages below 3V, and what is its minimum functional input?
Yes, the LTC3809IDD-1#TRPBF is specified to operate down to 2.75V input, making it suitable for single-cell Li-ion (2.7V–4.2V) and low-voltage USB-powered systems. Its UVLO turns on at 2.25V (rising) and off at 1.95V (falling), providing hysteresis to prevent oscillation near dropout. The 100% duty cycle capability allows regulation even when VIN approaches VOUT - critical for maximizing battery utilization. The LTC3809IDD-1#TRPBF maintains full functionality including current-mode control and protection features across its entire 2.75V–9.8V input range.
LTC3809IDD-1#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 10-WFDFN Exposed Pad
- Packaging:
- Tape & Reel (TR)
- 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):
- 2.75V ~ 9.8V
- Frequency - Switching:
- 550kHz
- Duty Cycle (Max):
- 100%
- Synchronous Rectifier:
- Yes
- Clock Sync:
- No
- Serial Interfaces:
- -
- Control Features:
- Enable, Soft Start, Tracking
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 10-DFN (3x3)
LTC3809IDD-1#TRPBF FAQ
1.How can I place an order for LTC3809IDD-1#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC3809IDD-1#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 LTC3809IDD-1#TRPBF reliable?
The price and inventory of LTC3809IDD-1#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC3809IDD-1#TRPBF is usually 5 days.
3.What payment methods are accepted for LTC3809IDD-1#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC3809IDD-1#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC3809IDD-1#TRPBF?
LTC3809IDD-1#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC3809IDD-1#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 LTC3809IDD-1#TRPBF?
For technical support, including LTC3809IDD-1#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC3809IDD-1#TRPBF requirements.
6.How does Aetrix verify that LTC3809IDD-1#TRPBF is sourced from the original manufacturer or authorized distributors?
All LTC3809IDD-1#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 LTC3809IDD-1#TRPBF meets industry standards.
7.What is the process for return or replacement of LTC3809IDD-1#TRPBF?
All LTC3809IDD-1#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC3809IDD-1#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 LTC3809IDD-1#TRPBF part is unused and in its original packaging.
Return procedure for LTC3809IDD-1#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC3809IDD-1#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…
