My Inquiry
My Account
Analog Devices Inc. LT8303ES5#TRMPBF
- Part No.:
- LT8303ES5#TRMPBF
- Manufacturer:
- Analog Devices Inc.
- Package:
- SOT-23-5 Thin, TSOT-23-5
- Datasheet:
-
LT8303ES5#TRMPBF.pdf
- Description:
- IC REG FLYBCK ADJ 450MA TSOT23-5
- Quantity:
- Payment:
- Shipping:
Inventory:1,061
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT8303ES5#TRMPBF from Analog Devices (formerly Linear Technology) is a micropower high-voltage isolated flyback controller IC with integrated 150V/450mA DMOS power switch, operating from 5.5V to 100V input and delivering up to 5W isolated output power. It regulates output voltage via primary-side flyback waveform sampling-eliminating opto-isolators and third windings-and uses a single external resistor (RFB) for VOUT programming in telecom, industrial, and medical auxiliary power supplies.
For engineers reviewing the LT8303ES5#TRMPBF datasheet, LT8303ES5#TRMPBF pinout, LT8303ES5#TRMPBF application, or LT8303ES5#TRMPBF equivalent, key selection considerations include its 5-lead TSOT-23 package, boundary mode + low-ripple Burst Mode operation, 70µA sleep-mode quiescent current, ±1% RFB regulation current (100µA), and 150V SW pin absolute maximum rating.
Technical Context
The LT8303ES5#TRMPBF implements current-mode control with a novel flyback pulse sense circuit and sample-and-hold error amplifier that samples the isolated output voltage during zero secondary current events. Its boundary conduction mode (BCM) at heavy load ensures excellent load regulation without external compensation, while discontinuous conduction mode (DCM) clamps max frequency to ~350kHz to limit switching losses.
At light loads, it enters low-ripple Burst Mode operation-alternating between active and sleep modes-with minimum 7kHz switching frequency to maintain accurate output sampling and achieve <0.5% full-load minimum load requirement. Internal 1.223V bandgap reference, 12.23kΩ trimmed RREF, and 2.5µA EN/UVLO hysteresis enable precise VIN undervoltage lockout programming.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 5.5V to 100V - supports wide-input industrial and telecom rails without pre-regulation |
| Integrated Switch | 150V/450mA DMOS - enables compact isolated flyback designs up to 5W without external MOSFET |
| RFB Regulation Current | 100µA ±2.5% - sets output voltage via single resistor; enables ±5% board-to-board VOUT accuracy |
| Quiescent Current | 70µA in Sleep Mode - minimizes no-load power loss in always-on auxiliary supplies |
| Switching Frequency | 5–380kHz variable - BCM at heavy load, DCM clamped ≤350kHz, Burst Mode ≥7kHz at light load |
| EN/UVLO Threshold | 1.223V rising / 1.186V falling - allows precise, hysteresis-programmable input UVLO using resistor divider |
| Min. Switch-On Time | 160ns - enforces leading-edge blanking to suppress turn-on current spike-induced instability |
Pinout & Package
LT8303ES5#TRMPBF is housed in a 5-lead ThinSOT™ (TSOT-23) package with exposed pad for thermal performance. Pin functions are validated per Linear Technology's official datasheet (Document 8303fa, Rev. G).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| EN/UVLO (Pin 1) | Enable / Input Undervoltage Lockout Input | Accurate 1.223V threshold with 2.5µA hysteresis; used to enable device or program VIN UVLO with resistor divider |
| GND (Pin 2) | Power Ground Reference | Primary ground return for internal regulators and feedback circuitry; must connect directly to local ground plane |
| RFB (Pin 3) | Feedback Resistor Connection | Connects external RFB to SW node; current through RFB (100µA) sets VOUT based on transformer turns ratio and diode VF |
| SW (Pin 4) | Drain of Integrated 150V DMOS Switch | High-voltage switching node; sees VIN + VOUT×NPS + leakage spike; requires minimized trace area for EMI control |
| VIN (Pin 5) | Main Input Supply | Powers internal circuitry and serves as reference for RFB feedback path; requires local ceramic bypass capacitor |
Key Features
| Feature | Design Value |
|---|---|
| Primary-side sensing architecture | Eliminates opto-isolator and third winding-reduces BOM count, cost, and size while improving long-term reliability |
| Boundary conduction mode (BCM) | Zero-current switching at every cycle improves load regulation and enables smaller magnetics vs. CCM |
| Low-ripple Burst Mode | Maintains <15mVpp output ripple at light load while achieving >80% efficiency down to 1mA output current |
| Internal compensation & soft-start | Reduces external component count by integrating loop compensation and controlled startup ramp |
| Accurate EN/UVLO with hysteresis | Enables robust input rail sequencing and brown-out protection without external comparators or references |
Applications
| Industrial PLC Auxiliary Power | Medical Isolated Sensor Bias |
|---|---|
Use Scenario: Providing isolated 5V/0.5A housekeeping power to microcontrollers and ADCs in programmable logic controllers operating from 24V–72V DC rails. IC Role / Device Role / Timing Role: Primary-side flyback controller regulating isolated output without optocoupler; manages BCM-to-Burst Mode transition across 0–100% load. Use Value: Enables compact, certified (IEC 61000-4-x) auxiliary supply meeting reinforced isolation requirements with <70µA no-load draw. | Use Scenario: Generating isolated ±3.3V bias for precision analog front-ends in patient-connected diagnostic sensors (e.g., ECG, EEG) powered from 12V battery or USB-C PD. IC Role / Device Role / Timing Role: Micropower isolated controller maintaining tight output regulation (±3%) over –40°C to +85°C with minimal temperature drift. Use Value: Delivers certified creepage/clearance (>8mm) and low EMI without third winding-critical for IEC 60601-1 compliance. |
| Telecom Remote Radio Unit (RRU) | Automotive ADAS Camera Module |
Use Scenario: Isolated 12V/250mA auxiliary supply for FPGAs and SerDes in outdoor macrocell RRUs powered from -48V DC telco plant. IC Role / Device Role / Timing Role: High-input flyback controller handling 5.5V–100V range; withstands load dump transients up to 100V with 150V SW rating. Use Value: Supports extended temperature operation (–40°C to +125°C) and achieves >85% peak efficiency at 75V input-reducing thermal stress in sealed enclosures. | Use Scenario: Isolated 5V/300mA power for image sensor and ISP in rear-view camera modules mounted near vehicle chassis. IC Role / Device Role / Timing Role: Compact flyback controller in TSOT-23 enabling PCB space savings vs. opto-based solutions; operates across automotive battery range (6V–18V). Use Value: Meets AEC-Q200 stress test requirements when paired with qualified magnetics; low 280µA active IQ extends battery backup runtime. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar isolated flyback controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LT3748EMS#PBF | Requires external MOSFET; higher 120V max input; no integrated switch; supports synchronous rectification | Better suited for >10W outputs or designs requiring tighter VOUT tolerance (<±1%) | Select when higher power, lower ripple, or synchronous rectifier control is required-accepts larger solution size and BOM count |
| UCC28740DR | TI part with 90V max input; 400mA/100V switch; different RFB scaling (10µA); no internal soft-start | Optimized for cost-sensitive consumer adapters; lacks 100V input capability and low-IQ sleep mode | Choose for 5–24V input applications where 100V rating is unnecessary and TI ecosystem support is preferred |
Compared with LT3748EMS#PBF and UCC28740DR, the LT8303ES5#TRMPBF uniquely combines 100V input rating, integrated 150V switch, 70µA sleep IQ, and primary-side sensing in a 5-lead TSOT-23-making it optimal for space-constrained, wide-input, ultra-low-no-load isolated supplies under 5W.
Availability
LT8303ES5#TRMPBF is available at Aetrix Electronics and suitable for industrial PLC auxiliary power, medical sensor bias, telecom RRU housekeeping, and automotive ADAS camera modules requiring stable component supply across extended temperature ranges and long production lifecycles.
Supply support for LT8303ES5#TRMPBF 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 all Linear parts including the LT8303 series.
The LT8303 belongs to Linear's isolated power controller product line, designed specifically to simplify high-voltage isolated flyback design by eliminating optocouplers and third windings while maintaining high efficiency and tight regulation across wide input and load ranges.
FAQ
What is the maximum output power achievable with LT8303ES5#TRMPBF?
The LT8303ES5#TRMPBF delivers up to 5W of isolated output power depending on input voltage, transformer turns ratio, and efficiency. At VIN = 48V with a 6:1 transformer, typical output is 5V/0.65A (3.25W); at VIN = 72V with optimized 8:1 winding, it reaches ~4.35W. The 450mA/150V internal switch and boundary mode operation define this practical limit-exceeding it risks SW pin overvoltage or thermal overload. Always verify transformer saturation current and leakage inductance per datasheet guidelines.
Does LT8303ES5#TRMPBF require an optocoupler or third winding for regulation?
No, the LT8303ES5#TRMPBF does not require an optocoupler or third winding. It regulates the isolated output voltage by sampling the reflected flyback pulse directly at the SW pin during zero secondary current events-a proprietary primary-side sensing method. This eliminates opto-isolator aging, nonlinearity, and layout complexity while reducing bill-of-materials count and cost. The technique is validated across temperature and line/load conditions per Linear Technology's characterization data.
What is the purpose of the RFB pin on LT8303ES5#TRMPBF, and how is output voltage set?
The RFB pin on LT8303ES5#TRMPBF connects to the SW node via an external resistor (RFB) and sources a precise 100µA regulation current. Output voltage is calculated as VOUT ≈ (100µA × RFB)/NPS − VF, where NPS is the transformer primary-to-secondary turns ratio and VF is the output diode forward voltage (~0.3V). For example, a 5V output with 6:1 turns ratio requires RFB ≈ 316kΩ. Final value must be fine-tuned empirically due to layout and transformer tolerances.
How does LT8303ES5#TRMPBF manage efficiency at light load?
The LT8303ES5#TRMPBF maintains high light-load efficiency using low-ripple Burst Mode operation: it alternates between active switching cycles and deep sleep mode (70µA IQ), reducing average input current while preserving output voltage accuracy. Minimum 7kHz burst frequency ensures sufficient sampling of the flyback pulse for regulation. Unlike standard burst modes, this implementation limits output ripple to <15mVpp at 1mA load-critical for noise-sensitive analog circuits powered by LT8303ES5#TRMPBF.
What is the operating temperature range for LT8303ES5#TRMPBF?
The LT8303ES5#TRMPBF is rated for an operating junction temperature range of –40°C to +125°C, matching the LT8303E grade specified in the official datasheet. This range is validated across all electrical parameters including RFB regulation current (100µA ±2.5%), EN/UVLO thresholds (1.223V ±0.016V), and switching frequency (5–380kHz). Derating applies above 125°C per Absolute Maximum Ratings-continuous operation beyond 125°C may impair long-term reliability.
LT8303ES5#TRMPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- SOT-23-5 Thin, TSOT-23-5
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Function:
- Step-Up/Step-Down
- Output Configuration:
- Positive, Isolation Capable
- Topology:
- Flyback
- Output Type:
- Adjustable
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 5.5V
- Voltage - Input (Max):
- 100V
- Voltage - Output (Min/Fixed):
- -
- Voltage - Output (Max):
- -
- Current - Output:
- 450mA
- Frequency - Switching:
- 7kHz ~ 350kHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TSOT-23-5
LT8303ES5#TRMPBF FAQ
1.How can I place an order for LT8303ES5#TRMPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT8303ES5#TRMPBF 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 LT8303ES5#TRMPBF reliable?
The price and inventory of LT8303ES5#TRMPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT8303ES5#TRMPBF is usually 5 days.
3.What payment methods are accepted for LT8303ES5#TRMPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT8303ES5#TRMPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT8303ES5#TRMPBF?
LT8303ES5#TRMPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT8303ES5#TRMPBF 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 LT8303ES5#TRMPBF?
For technical support, including LT8303ES5#TRMPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT8303ES5#TRMPBF requirements.
6.How does Aetrix verify that LT8303ES5#TRMPBF is sourced from the original manufacturer or authorized distributors?
All LT8303ES5#TRMPBF 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 LT8303ES5#TRMPBF meets industry standards.
7.What is the process for return or replacement of LT8303ES5#TRMPBF?
All LT8303ES5#TRMPBF units undergo pre-shipment inspection (PSI). If there is an issue with LT8303ES5#TRMPBF, 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 LT8303ES5#TRMPBF part is unused and in its original packaging.
Return procedure for LT8303ES5#TRMPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT8303ES5#TRMPBF Tags
-
TPS562201DDCR
Texas Instruments
-
MC34063ABD-TR
STMicroelectronics
-
TPS561201DDCR
Texas Instruments
-
MC33063ADR
Texas Instruments
-
MC34063ADR
Texas Instruments
-
TPS560200DBVR
Texas Instruments
-
AP3012KTR-G1
Diodes Incorporated
-
TLV61048DBVR
Texas Instruments
-
AZ34063UMTR-G1
Diodes Incorporated
-
TPS562200DDCR
Texas Instruments
-
AP62300TWU-7
Diodes Incorporated
-
MC34063EBD-TR
STMicroelectronics
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…
