My Inquiry
My Account
Analog Devices Inc. LT8312EMS#TRPBF
- Part No.:
- LT8312EMS#TRPBF
- Manufacturer:
- Analog Devices Inc.
- Category:
- PFC (Power Factor Correction)
- Package:
- 16-TFSOP (0.118", 3.00mm Width)
- Datasheet:
-
LT8312EMS#TRPBF.pdf
- Description:
- IC PFC CTRLR DCM 400KHZ 16MSOP
- Quantity:
- Payment:
- Shipping:
Inventory:1,596
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LT8312EMS#TRPBF from Analog Devices (formerly Linear Technology) is a critical conduction mode (CrCM) power factor correction (PFC) boost controller IC designed for offline AC-DC front-end stages. It delivers >0.99 power factor, <5% THD at 200W, 95% peak efficiency, and operates across universal 90–265VAC input with 400VDC output capability.
For engineers reviewing the LT8312EMS#TRPBF datasheet, LT8312EMS#TRPBF pinout, LT8312EMS#TRPBF application, or LT8312EMS#TRPBF equivalent, this page provides verified technical context, validated pin functions, real-world PFC design constraints, and confirmed alternative controllers for industrial and avionics-grade boost PFC implementations.
Technical Context
The LT8312EMS#TRPBF implements active PFC using line-voltage-sensed current limit modulation via the VIN(SENSE) pin and a dedicated internal multiplier. Its CrCM operation relies on DCM detection through an auxiliary winding coupled to the DCM pin, enabling zero-voltage turn-on and up to 5% efficiency gain over fixed-frequency alternatives.
It integrates a 10V LDO (INTVCC), 1.9A gate driver, 1.25V FB reference, 2V VREF output, and programmable EN/UVLO with 1.25V threshold and 10µA hysteresis. The control loop uses a transconductance error amplifier (170 µmhos) with VC compensation, requiring unity-gain bandwidth <12Hz for stable PFC performance.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Topology | Critical conduction mode (CrCM) boost PFC controller - enables zero-voltage switching and low EMI without external timing components. |
| Input Voltage Range | 90–265VAC universal line - supports global mains without hardware reconfiguration. |
| Power Factor | >0.99 at full load - meets IEC 61000-3-2 Class C/D harmonic limits for lighting and industrial equipment. |
| Peak Efficiency | 95% at 200W - achieved via CrCM operation, low-loss gate drive, and optimized internal regulation. |
| Max Oscillator Frequency | 400kHz - clamps natural CrCM frequency to prevent MOSFET stress at light loads. |
| SENSE Threshold | 102mV typical - sets peak inductor current; minimum 3mV limit improves crossover distortion. |
| FB Reference Voltage | 1.25V ±3% - regulates output voltage via external resistor divider; line regulation <0.03%/V. |
| EN/UVLO Threshold | 1.25V rising, with 10µA hysteresis - enables micropower start-up and robust brown-out recovery. |
Pinout & Package
LT8312EMS#TRPBF is housed in a 16-lead plastic MSOP package (3.0mm × 4.0mm, 0.5mm pitch) with exposed pad for thermal enhancement. Pin 1 is marked by a dot; pins are numbered counterclockwise from top-left corner in top view.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| GND (1,2,3,7,8) | Ground reference | Five dedicated ground pins minimize PCB impedance and improve noise immunity in high-dI/dt PFC paths. |
| VREF (4) | 2V reference output | Drives OVP divider; supplies ≤200µA - enables accurate overvoltage protection without external regulator. |
| OVP (5) | Overvoltage protection comparator input | Shuts down switching when FB exceeds VREF-based threshold - protects downstream DC-DC stages. |
| VC (6) | Error amplifier output | Compensation node for feedback loop; requires RC network to ground for stability in PFC applications. |
| FB (9) | Voltage feedback input | Senses output voltage via resistor divider; 1.25V reference enables precise regulation of 400VDC bus. |
| DCM (10) | Discontinuous conduction mode detector | Accepts AC-coupled signal from auxiliary winding - triggers zero-voltage turn-on by detecting dv/dt ring. |
| VIN (11) | Startup and bias supply input | Internally shunted to 40V/8mA; powers INTVCC LDO - eliminates need for external startup circuitry. |
| EN/UVLO (12) | Enable and undervoltage lockout | Configurable turn-on/off thresholds via resistor divider - ensures reliable start-up across wide input range. |
| INTVCC (13) | Regulated 10V supply output | Powers internal circuitry and gate driver; requires 4.7µF local ceramic bypass for stability. |
| GATE (14) | N-channel MOSFET gate driver | 1.9A sink/source capability - directly drives high-voltage MOSFETs like IPA50R190CE without buffer. |
| SENSE (15) | Current sense input | Kelvin-connected to RSENSE source - measures switch current with 102mV threshold and 90ns blanking. |
| VIN(SENSE) (16) | Line voltage sensing input | Feeds internal multiplier for PFC - resistor sets 360µA current at max line voltage to scale current limit. |
Key Features
| Feature | Design Value |
|---|---|
| Active Power Factor Correction | Enables >0.99 PF and <5% THD without external multipliers or DSP - meets Energy Star and IEC 61000-3-2. |
| Critical Conduction Mode Control | Self-oscillating CrCM with DCM detection - eliminates need for external clock and reduces component count. |
| Integrated 10V LDO | Derives INTVCC from VIN with 500mV dropout - removes external bias supply and simplifies BOM. |
| 1.9A Gate Driver | Directly drives high-QG MOSFETs - supports fast switching with minimal external drive components. |
| No-Load Power Consumption | <0.5W at 230VAC - satisfies Energy Star standby requirements for industrial power supplies. |
| Robust Protection Suite | Includes OVP, UVLO, overcurrent (SENSE), and internal VIN clamp - reduces need for discrete protection circuits. |
Applications
| Industrial Motor Drives | Avionics Power Supplies |
|---|---|
|
Use Scenario: 3-phase motor drive front-end with regenerative braking and harmonic compliance requirements. IC Role / Device Role / Timing Role: PFC boost controller regulating 400V DC bus while maintaining >0.99 power factor under variable load. Use Value: Enables IEC 61000-3-2 Class A compliance and reduces RMS input current by 30% vs. passive PFC. |
Use Scenario: 400Hz aircraft power system converting 97–134VAC to regulated 28V DC via two-stage conversion. IC Role / Device Role / Timing Role: First-stage CrCM PFC controller delivering stable 400V intermediate bus for downstream isolated DC-DC. Use Value: Achieves 95% efficiency at 60W with 125°C junction rating - meets DO-160E environmental stress requirements. |
| LED Street Lighting | Medical Imaging Power Systems |
|
Use Scenario: Outdoor LED luminaire requiring high-efficiency, long-life power supply with Class C harmonic compliance. IC Role / Device Role / Timing Role: Universal-input PFC controller driving 400V bus for constant-current LED driver stage. Use Value: Delivers <0.5W no-load consumption and >95% efficiency - extends thermal lifetime in sealed enclosures. |
Use Scenario: CT/MRI scanner power supply needing ultra-low EMI, high reliability, and strict harmonic control. IC Role / Device Role / Timing Role: Front-end PFC controller operating in CrCM to minimize conducted emissions into sensitive analog subsystems. Use Value: Reduces 3rd/5th harmonic currents by >80% vs. diode-bridge rectification - eases EMI filter design. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar PFC boost controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LT3798 | Combines active PFC + isolated flyback in single IC; requires optocoupler; higher BOM cost. | Targeted at space-constrained, isolated-output systems where galvanic separation is mandatory. | Select LT3798 only when isolation and PFC integration justify added complexity and cost. |
| UCC28070 | Fixed-frequency average-current-mode PFC; no CrCM operation; requires external multiplier and oscillator. | Better suited for high-power (>300W), continuous conduction mode designs with tighter output voltage regulation needs. | Choose UCC28070 for high-power industrial PSUs where fixed-frequency control simplifies EMI filtering. |
Compared with LT8312EMS#TRPBF, LT3798 adds isolation but increases layout complexity and cost, while UCC28070 offers superior voltage regulation at the expense of higher THD and reduced light-load efficiency - making LT8312EMS#TRPBF optimal for universal-input, medium-power CrCM PFC where simplicity and harmonic performance are prioritized.
Availability
LT8312EMS#TRPBF is available at Aetrix Electronics and suitable for industrial motor drives, avionics power supplies, and LED street lighting requiring stable component supply, extended temperature operation (–40°C to 125°C), and long-term PFC controller availability.
Supply support for LT8312EMS#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, datasheet documentation, and application engineering for legacy Linear parts including the LT8312 series.
The LT8312 belongs to Linear's high-voltage power management portfolio, specifically engineered for compact, efficient, and standards-compliant AC-DC front-end conversion in space- and thermal-constrained environments.
FAQ
What is the maximum output power achievable with the LT8312EMS#TRPBF in a well-designed PFC boost stage?
The LT8312EMS#TRPBF supports up to 250W output power in optimized designs, as confirmed in the datasheet's Typical Application section. At 200W universal input (90–265VAC), it achieves >95% peak efficiency and >0.99 power factor. Thermal design, MOSFET selection (e.g., IPA50R190CE), and inductor sizing must align with the 125°C junction rating and 400kHz max switching frequency to sustain full-rated power.
Does the LT8312EMS#TRPBF require an external clock or can it operate autonomously in critical conduction mode?
The LT8312EMS#TRPBF operates autonomously in critical conduction mode without any external clock. It uses the DCM pin to detect ringing on the transformer auxiliary winding and self-times each switching cycle based on inductor current zero-crossing. This eliminates timing components and simplifies design versus fixed-frequency PFC controllers like the UCC28070.
How does the LT8312EMS#TRPBF implement power factor correction without a digital controller or external multiplier?
The LT8312EMS#TRPBF implements analog PFC using an internal multiplier that scales the SENSE current limit threshold proportionally to the voltage applied to the VIN(SENSE) pin. When a resistor connects VIN(SENSE) to the rectified AC line, the resulting current modulates the peak switch current in phase with the input voltage - achieving >0.99 PF without external multipliers or firmware.
What is the purpose of the five GND pins on the LT8312EMS#TRPBF MSOP package?
The LT8312EMS#TRPBF allocates five dedicated GND pins (pins 1, 2, 3, 7, 8) to separate high-current power return paths from sensitive analog ground references. This minimizes voltage spikes on the FB, SENSE, and VC nodes caused by switching currents, improving regulation accuracy, current-sense fidelity, and loop stability in high-dI/dt PFC applications.
Can the LT8312EMS#TRPBF be used in 400Hz avionics applications, and what design adjustments are required?
Yes, the LT8312EMS#TRPBF is qualified for avionics use, as demonstrated in the datasheet's "Avionics Input 60W PFC Boost Converter" reference design (TA03). Key adjustments include scaling the VIN(SENSE) resistor for 97–134VAC/400Hz input, selecting a higher-inductance boost choke (750µH), and verifying DCM timing with the auxiliary winding turns ratio to maintain reliable zero-voltage switching at higher line frequency.
LT8312EMS#TRPBF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Analog Devices Inc.
- Series:
- -
- Package/Case:
- 16-TFSOP (0.118", 3.00mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Mode:
- Discontinuous Conduction (DCM)
- Frequency - Switching:
- 400kHz
- Current - Startup:
- 80 µA
- Voltage - Supply:
- 10V ~ 38V
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 16-MSOP
LT8312EMS#TRPBF FAQ
1.How can I place an order for LT8312EMS#TRPBF through Aetrix?
Please submit a Request for Quotation (RFQ) for LT8312EMS#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 LT8312EMS#TRPBF reliable?
The price and inventory of LT8312EMS#TRPBF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LT8312EMS#TRPBF is usually 5 days.
3.What payment methods are accepted for LT8312EMS#TRPBF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LT8312EMS#TRPBF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LT8312EMS#TRPBF?
LT8312EMS#TRPBF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LT8312EMS#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 LT8312EMS#TRPBF?
For technical support, including LT8312EMS#TRPBF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LT8312EMS#TRPBF requirements.
6.How does Aetrix verify that LT8312EMS#TRPBF is sourced from the original manufacturer or authorized distributors?
All LT8312EMS#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 LT8312EMS#TRPBF meets industry standards.
7.What is the process for return or replacement of LT8312EMS#TRPBF?
All LT8312EMS#TRPBF units undergo pre-shipment inspection (PSI). If there is an issue with LT8312EMS#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 LT8312EMS#TRPBF part is unused and in its original packaging.
Return procedure for LT8312EMS#TRPBF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LT8312EMS#TRPBF Tags
-
ICE2PCS01GXUMA1
Infineon Technologies
-
NCP1654BD133R2G
onsemi
-
MC33262DR2G
onsemi
-
ICE3PCS03GXUMA1
Infineon Technologies
-
NCP1631DR2G
onsemi
-
L4981BD013TR
STMicroelectronics
-
UCC28070DWR
Texas Instruments
-
UCC28070PWR
Texas Instruments
-
UC3854DWTR
Texas Instruments
-
L4981AD013TR
STMicroelectronics
-
UCC2817D
Texas Instruments
-
UC2854BDWTR
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…
