My Inquiry
My Account
Analog Devices Inc. LTC3803ES6#TRPBF
- Part No.:
- LTC3803ES6#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- DC DC Switching Controllers
- Package:
- SOT-23-6 Thin, TSOT-23-6
- Datasheet:
-
LTC3803ES6#TRPBF.pdf
- Description:
- IC REG CTRLR FLYBACK TSOT23-6
- Quantity:
- Payment:
- Shipping:
Inventory:4,588
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LTC3803ES6#TRPBF from Analog Devices (formerly Linear Technology) is a constant-frequency current-mode flyback DC/DC controller optimized for driving external N-channel MOSFETs in high-input-voltage telecom and industrial power supplies. It delivers ±1.5% output voltage accuracy, 200 kHz fixed switching frequency, 240 μA quiescent current, and operates across –40°C to 125°C. Used in nonisolated 5 V/2 A housekeeping supplies with 36–72 V input.
For engineers reviewing the LTC3803ES6#TRPBF datasheet, LTC3803ES6#TRPBF pinout, LTC3803ES6#TRPBF application, or LTC3803ES6#TRPBF equivalent, key selection criteria include its ground-referenced current sensing architecture, programmable slope compensation via external resistor, internal soft-start (1.4 ms), VCC shunt regulation (9.5 V), and undervoltage lockout with 3.0 V hysteresis - all critical for stable high-VIN flyback design.
Technical Context
The LTC3803ES6#TRPBF implements a current-mode control loop where the ITH/RUN pin voltage directly sets the peak current comparator threshold, enabling precise load and line transient response. Its 200 kHz oscillator drives an RS latch that controls NGATE, with duty cycle limited to 6–80% and automatic blanking during MOSFET turn-on.
It features dual startup mechanisms: micropower hysteretic start-up via external RSTART/CVCC, and internal VCC shunt regulation (clamp at 9.5 V, 25 mA max) allowing direct high-VIN biasing. The SENSE pin injects a linear 0–5 μA ramp for slope compensation, while VFB regulates to 800 mV with ±1.5% accuracy over temperature.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Oscillator Frequency | 200 kHz fixed - ensures predictable EMI profile and simplifies filter design without frequency jitter. |
| Output Voltage Accuracy | ±1.5% - enables tight regulation of 5 V housekeeping rails without post-regulation. |
| Quiescent Current | 240 μA - supports ultra-low standby power in always-on telecom systems. |
| VCC Shunt Clamp | 9.5 V typical - permits direct biasing from 36–72 V inputs using a single series resistor. |
| UVLO Hysteresis | 3.0 V - wide hysteresis enables reliable self-starting from transformer bias windings. |
| Slope Compensation | 0–5 μA programmable ramp - stabilizes current-mode control above 50% duty cycle. |
| Soft-Start Time | 1.4 ms - prevents inrush current stress on input capacitors and MOSFETs. |
Pinout & Package
Package: 6-lead TSOT-23 (ThinSOT™), 1 mm profile, rated for –40°C to 125°C junction temperature.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| ITH/RUN (1) | Error amplifier output & shutdown control | Sets current comparator threshold (0.7–1.9 V); <0.28 V forces shutdown; hosts RC compensation network. |
| GND (2) | Power and signal reference | Ground return for VCC, NGATE, SENSE, and feedback divider - must be low-impedance. |
| VFB (3) | Feedback input | Compares output voltage (via resistive divider) to 800 mV internal reference for regulation. |
| SENSE (4) | Current sense & slope ramp injection | Monitors MOSFET source current; injects 5 μA ramp for slope compensation when RSL present. |
| VCC (5) | Supply input with shunt regulator | Internally clamped to ~9.5 V; accepts up to 25 mA sink current for high-VIN resistor biasing. |
| NGATE (6) | N-MOSFET gate driver | Push-pull output swinging 0 V to VCC; drives external MOSFET gate with 40 ns rise/fall times. |
Key Features
| Feature | Design Value |
|---|---|
| Ground-referenced current sensing | Enables high-side primary-side sensing without level-shifting circuitry or isolated amplifiers. |
| Internal VCC shunt regulator | Eliminates need for external LDO or bias winding - simplifies 48 V+ input designs with one resistor. |
| Adjustable slope compensation | Prevents subharmonic oscillation in continuous conduction mode flyback without dedicated ICs. |
| No minimum load requirement | Supports light-load efficiency in standby modes without dummy loads or burst-mode complexity. |
| Micropower hysteretic start-up | Enables self-sustaining operation from transformer bias winding after initial trickle charge. |
Applications
| Telecom Housekeeping Supply | Automotive Auxiliary Power |
|---|---|
Use Scenario: Nonisolated 5 V/2 A supply in 48 V telecom shelf systems, powered from 36–72 V backplane. IC Role / Device Role / Timing Role: Flyback controller regulating output via VFB feedback; NGATE drives primary-side N-MOSFET; SENSE monitors peak current. Use Value: ±1.5% accuracy and 240 μA quiescent current ensure stable logic rail generation with minimal standby loss. | Use Scenario: 12 V auxiliary supply in 42 V automotive subsystems (e.g., ADAS camera modules). IC Role / Device Role / Timing Role: Constant-frequency current-mode controller managing wide VIN transients; UVLO hysteresis rejects cold-crank dips. Use Value: 3.0 V UVLO hysteresis and 150°C-rated variants (LTC3803H) support robust operation under engine-bay thermal stress. |
| Power over Ethernet (PoE) | Industrial Control System PSU |
Use Scenario: Secondary-side 5 V/1 A converter in PoE-powered access points, accepting up to 57 V input. IC Role / Device Role / Timing Role: Flyback controller with ground-referenced sensing - avoids isolation barrier complications for current monitoring. Use Value: Adjustable slope compensation stabilizes regulation across varying cable lengths and load profiles. | Use Scenario: 24 V input to 5 V/1.5 A isolated housekeeping supply in PLC I/O modules. IC Role / Device Role / Timing Role: Controller driving discrete N-MOSFET; VCC shunt regulation enables simple resistor-fed bias from 24 V rail. Use Value: Internal soft-start (1.4 ms) prevents inrush-induced brownouts during hot-swap insertion of field modules. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar flyback controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| UCC28C43DR | Fixed 200 kHz frequency, but no internal VCC shunt regulator; requires external bias supply or winding. | Lacks ground-referenced current sensing - needs high-side sense or optocoupler feedback for isolation. | Choose UCC28C43DR only if external bias is already available and slope compensation is handled externally. |
| MAX5021ASA+ | Higher 250 kHz frequency; ±2% reference accuracy; no programmable slope compensation ramp. | Designed for lower-VIN applications (≤28 V); lacks VCC clamp for direct high-VIN resistor biasing. | Select MAX5021ASA+ for cost-sensitive 12–24 V systems where 200 kHz EMI profile isn't mandatory. |
Compared with UCC28C43DR and MAX5021ASA+, the LTC3803ES6#TRPBF uniquely integrates VCC shunt regulation, ground-referenced sensing, and programmable slope compensation - making it optimal for compact, high-VIN flyback designs requiring minimal external components and robust startup behavior.
Availability
LTC3803ES6#TRPBF is available at Aetrix Electronics and suitable for telecom housekeeping supplies, automotive auxiliary power, and industrial control system PSUs requiring stable component supply across extended temperature ranges.
Supply support for LTC3803ES6#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 full product support, documentation, and manufacturing continuity for legacy Linear parts including the LTC3803 family.
The LTC3803 belongs to Linear's high-VIN flyback controller product line, designed specifically for efficient, compact, and robust housekeeping power in telecom, automotive, and industrial systems with input voltages exceeding 36 V.
FAQ
What is the operating temperature range for the LTC3803ES6#TRPBF?
The LTC3803ES6#TRPBF is rated for –40°C to +125°C junction temperature. This grade ('E' suffix) is validated across the full range per datasheet specifications, with guaranteed performance including ±1.5% VFB accuracy and 200 kHz oscillator stability. Derating applies above 125°C ambient depending on PCB layout and power dissipation.
Can the LTC3803ES6#TRPBF be powered directly from a 48 V input?
Yes - the LTC3803ES6#TRPBF can be powered directly from 48 V using a series resistor into the VCC pin. Its internal shunt regulator clamps VCC to ~9.5 V and sinks up to 25 mA, enabling simple resistor-based biasing without external regulators or transformer windings.
Does the LTC3803ES6#TRPBF require an external slope compensation resistor?
No - the LTC3803ES6#TRPBF includes an internal 0–5 μA programmable ramp injected at the SENSE pin. An external resistor (RSL) is optional and only needed for stabilization in continuous conduction mode flyback designs operating above 50% duty cycle.
What is the purpose of the ITH/RUN pin on the LTC3803ES6#TRPBF?
The ITH/RUN pin on the LTC3803ES6#TRPBF serves two functions: it is the error amplifier output (setting current comparator threshold) and the run/shutdown control input. Pulling it below 0.28 V disables the controller; in normal operation, its voltage (0.7–1.9 V) commands peak current limit and hosts the loop compensation network.
How does the LTC3803ES6#TRPBF achieve stable startup from high input voltages?
The LTC3803ES6#TRPBF achieves stable startup via micropower hysteretic start-up: an external RSTART/CVCC network trickle-charges VCC until it reaches 8.7 V (VTURNON), triggering operation. Its wide 3.0 V UVLO hysteresis (VTURNON–VTURNOFF) prevents oscillation during bias-winding takeover, ensuring clean transition to steady-state operation.
LTC3803ES6#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- SOT-23-6 Thin, TSOT-23-6
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Output Type:
- Transistor Driver
- Function:
- Step-Up/Step-Down
- Output Configuration:
- Positive, Isolation Capable
- Topology:
- Flyback
- Number of Outputs:
- 1
- Output Phases:
- 1
- Voltage - Supply (Vcc/Vdd):
- 5.7V ~ 8V
- Frequency - Switching:
- 200kHz
- Duty Cycle (Max):
- 80%
- Synchronous Rectifier:
- No
- Clock Sync:
- No
- Serial Interfaces:
- -
- Control Features:
- Current Limit, Enable
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TSOT-23-6
LTC3803ES6#TRPBF FAQ
1.How can I place an order for LTC3803ES6#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LTC3803ES6#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 LTC3803ES6#TRPBF reliable?
The price and inventory of LTC3803ES6#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LTC3803ES6#TRPBF is usually 5 days.
3.What payment methods are accepted for LTC3803ES6#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LTC3803ES6#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LTC3803ES6#TRPBF?
LTC3803ES6#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LTC3803ES6#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 LTC3803ES6#TRPBF?
For technical support, including LTC3803ES6#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LTC3803ES6#TRPBF requirements.
6.How does Aetrix verify that LTC3803ES6#TRPBF is sourced from the original manufacturer or authorized distributors?
All LTC3803ES6#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 LTC3803ES6#TRPBF meets industry standards.
7.What is the process for return or replacement of LTC3803ES6#TRPBF?
All LTC3803ES6#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LTC3803ES6#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 LTC3803ES6#TRPBF part is unused and in its original packaging.
Return procedure for LTC3803ES6#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LTC3803ES6#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…
