My Inquiry
My Account
Texas Instruments UC3852DTR
- Part No.:
- UC3852DTR
- Manufacturer:
- Texas Instruments
- Category:
- PFC (Power Factor Correction)
- Package:
- 8-SOIC (0.154", 3.90mm Width)
- Datasheet:
-
UC3852DTR.pdf
- Description:
- IC PFC CTRLR CCM 200KHZ 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:3,669
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
UC3852DTR from Texas Instruments is a high-power-factor preregulator controller IC designed for zero-current-switched boost PFC stages in AC-DC front-ends. It delivers >0.99 power factor, supports 50–500 W systems, features controlled on-time PWM, integrated zero-current sensing, and operates from 0°C to +70°C in SOIC-8 package.
For engineers reviewing the UC3852DTR datasheet, UC3852DTR pinout, UC3852DTR application, or UC3852DTR equivalent, this device is selected for cost-sensitive, low-harmonic-input AC-DC converters requiring regulated 400 VDC bulk output with <10% THD across 90–160 VAC input.
Technical Context
The UC3852DTR implements a variable-frequency, zero-current-switched (ZCS) boost topology where switch on-time is controlled by the error amplifier output (COMP), off-time is determined by inductor discharge, and cycle restart is triggered by zero-current detection at ISNS. Its RAMP timer uses externally programmed charge current (via ISET resistor) and timing capacitor to set maximum on-time and frequency limits.
It integrates under-voltage lockout (UVLO) with 16.3 V turn-on/11.5 V turn-off thresholds, peak-current limiting via ISNS fault threshold (–450 mV typical), and high-current gate drive (±1 A peak) with active low-state during UVLO. The ISET pin serves triple function: RAMP current programming, 5 V reference output, and FAULT signaling at ~9 V.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VCC UVLO Turn-On | 16.3 V typical - ensures stable startup only after sufficient bias supply is established |
| ISNS Fault Threshold | –450 mV typical - sets precise overcurrent trip point for boost switch protection |
| RAMP Charge Current | 98 µA typical - determines on-time slope and max switching frequency when combined with external Ct |
| OUT Peak Drive Current | ±1.0 A - directly drives power MOSFET gates without external buffer in ≤100 W designs |
| Power Factor | >0.99 - meets IEC 61000-3-2 Class D harmonic limits for lighting and SMPS applications |
| Operating Temp Range | 0°C to +70°C - qualified for commercial-grade AC-DC power supplies and industrial adapters |
| ISET Reference Voltage | 5.0 V ±10% - provides stable bias for RAMP programming and optional external monitoring |
Pinout & Package
UC3852DTR is housed in an 8-pin SOIC (D) package per JEDEC MS-012, with gull-wing leads, 1.27 mm pitch, and RoHS-compliant NiPdAu lead finish. Thermal resistance θJA = 120°C/W (SOIC-8, 2-layer board).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| GND (Pin 1) | Signal and power ground reference | Common return for all internal circuits; must be low-impedance connection to minimize noise coupling into ISNS and COMP |
| OUT (Pin 2) | High-current gate driver output | Drives MOSFET gate with ±1 A peak; actively held low during UVLO to prevent unintended switch turn-on |
| ISET (Pin 3) | RAMP current programming / 5 V reference / FAULT flag | Resistor from ISET to GND sets RAMP charging current (~5 V/R); pulled to ~9 V during overcurrent fault |
| ISNS (Pin 4) | Zero- and over-current sense input | Accepts ±5 V range; detects inductor zero-crossing for ZCS restart and –450 mV for fault shutdown |
| RAMP (Pin 5) | Timer capacitor node | Charged by ISET current; compared against PWM threshold (4.3 V) to terminate on-time; discharge path enables zero-current detection |
| VFB (Pin 6) | Error amplifier inverting input | Connects to voltage divider from bulk DC output; sets regulation point (typically 5.0 V at VFB for 400 V output) |
| COMP (Pin 7) | Error amplifier output / PWM comparator input | Integrates feedback error; clamped to ~10 V to limit max on-time; used for soft-start ramp control |
| VCC (Pin 8) | Supply input | Accepts 10–30 V; includes 30 V clamp; draws 3–10 mA active current; powers internal logic and OUT driver |
Key Features
| Feature | Design Value |
|---|---|
| Controlled On-Time Boost PWM | Enables fixed-output-voltage regulation without line-voltage feedforward, simplifying loop design and reducing component count |
| Zero-Current Switching (ZCS) | Reduces EMI and switching losses by ensuring MOSFET turns on only when inductor current reaches zero |
| Integrated UVLO with 5 V hysteresis | Prevents erratic operation during brownout or soft-start; guarantees clean enable/disable sequencing |
| Triple-function ISET pin | Eliminates need for separate reference, timing, and fault-reporting circuitry-reducing BOM and layout area |
| High-current ±1 A OUT driver | Directly drives IRF830-class MOSFETs up to 100 W without external buffers, lowering system cost and propagation delay |
Applications
| LED Driver Front-End | PC Power Supply PFC Stage |
|---|---|
|
Use Scenario: 100 W constant-current LED driver operating from universal AC input (90–264 VAC) with strict THD requirements. IC Role / Device Role / Timing Role: UC3852DTR acts as the active PFC controller in a boost preregulator, generating sinusoidal input current synchronized to AC line and regulating 400 VDC bus. Use Value: Achieves >0.995 PF and <10% THD per IEC 61000-3-2, enabling compliance without bulky passive filters or complex digital control. |
Use Scenario: ATX-compatible desktop PSU requiring 300 W continuous output with Class D harmonic compliance. IC Role / Device Role / Timing Role: UC3852DTR controls the boost converter that shapes input current and maintains stable 380–400 VDC bulk rail prior to main LLC stage. Use Value: Enables single-stage PFC with minimal external parts (1 inductor, 1 sense resistor, 1 timing cap), reducing bill-of-materials and board space vs. UC3854-based designs. |
| Industrial AC-DC Adapter | Medical Equipment Power Module |
|
Use Scenario: 250 W medical-grade AC-DC adapter certified to IEC 60601-1 with reinforced isolation and low leakage current. IC Role / Device Role / Timing Role: UC3852DTR manages boost PFC stage upstream of isolated DC-DC converters, ensuring low input harmonic distortion while supporting wide input range (85–265 VAC). Use Value: Delivers stable 400 VDC output with <5% load regulation from 10–100% load, minimizing stress on downstream isolation transformers and capacitors. |
Use Scenario: Portable ultrasound system requiring ultra-low EMI and reliable operation in battery-charging mode with AC input. IC Role / Device Role / Timing Role: UC3852DTR implements ZCS boost PFC to suppress high-frequency conducted emissions, critical for sensitive analog front-end signal integrity. Use Value: Zero-current switching reduces radiated emissions above 30 MHz by >10 dB compared to continuous-conduction-mode controllers, easing EMC certification. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar power factor correction controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| UC3854DTR | Continuous-conduction-mode (CCM) controller with feedforward line voltage compensation; higher pin count (16-pin SOIC); requires external current-sense transformer | Better suited for >500 W, high-precision PFC where THD <5% and tight line regulation are required | Select UC3854DTR when designing >300 W systems needing CCM stability and lower RMS input current ripple |
| L6562ADTR | Fixed-frequency average-current-mode controller; 8-pin SOIC; built-in zero-cross detection; no RAMP pin or ISET programming | Optimized for cost-sensitive lighting ballasts and adapters where simplicity and fast time-to-market outweigh ZCS EMI benefits | Choose L6562ADTR for 30–150 W designs prioritizing ease of layout and reduced external component count over ultra-low THD |
Compared with UC3854DTR and L6562ADTR, the UC3852DTR uniquely balances low THD (<10%), ZCS EMI reduction, and minimal external parts-making it optimal for 50–250 W commercial/industrial PFC where SOIC-8 footprint and thermal performance are constraints.
Availability
UC3852DTR is available at Aetrix Electronics and suitable for LED drivers, PC power supplies, industrial AC-DC adapters, and medical equipment power modules requiring stable component supply and long-term manufacturability.
Supply support for UC3852DTR 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
Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and power management technologies, with decades of heritage in power conversion ICs.
The UC3852DTR belongs to TI's legacy Unitrode PFC controller family, engineered specifically for cost-effective, high-efficiency active power factor correction in mid-power AC-DC systems.
FAQ
What is the recommended minimum RAMP capacitor value for stable operation of the UC3852DTR?
The UC3852DTR datasheet specifies a recommended RAMP capacitor range of 100 pF to 1 nF. For stable zero-current switching across full load and line range, 300 pF is commonly used with a 50 kΩ ISET resistor, yielding ~100 kHz max frequency and robust noise immunity. Values below 100 pF risk premature RAMP discharge and erratic restart timing.
Does the UC3852DTR support soft-start functionality, and how is it implemented?
Yes, the UC3852DTR supports soft-start via the COMP pin. To implement it, connect a PNP transistor, resistor, and capacitor between VCC and COMP so that COMP voltage ramps up gradually at power-on. This linearly increases on-time, limiting inrush current into the boost inductor and preventing output overshoot. The UC3852DTR does not include internal soft-start circuitry.
Can the UC3852DTR operate with a 12 V VCC supply, and what are the implications?
No-the UC3852DTR requires a minimum VCC of 14.5 V to exit UVLO (typical turn-on threshold). A 12 V supply will keep the device latched in UVLO, disabling OUT and halting operation. Designers must ensure VCC is derived from a ≥15 V auxiliary winding or post-bridge rail with adequate hold-up capacitance to sustain operation during AC dips.
How does the UC3852DTR achieve zero-current switching without a dedicated ZCD pin?
The UC3852DTR achieves zero-current switching using its ISNS pin and internal RAMP discharge path. When inductor current falls to zero, ISNS voltage rises toward GND, triggering internal discharge of the RAMP capacitor. Once RAMP voltage drops below the PWM comparator threshold (~4.3 V), the next on-cycle begins-ensuring MOSFET turn-on occurs precisely at current zero crossing.
Is the UC3852DTR pin-compatible with the UC3852N (PDIP-8) version?
Yes-the UC3852DTR (SOIC-8) and UC3852N (PDIP-8) share identical pinout, electrical specifications, and functional behavior. Both use the same DIL-8/SOIC-8 pin mapping per UDG-92001 and UDG-92002 diagrams. Layout changes are required only for package footprint and thermal relief, not signal routing.
UC3852DTR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width)
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Mode:
- Continuous Conduction (CCM)
- Frequency - Switching:
- 200kHz
- Current - Startup:
- 400 µA
- Voltage - Supply:
- 14.5V ~ 30V
- Operating Temperature:
- 0°C ~ 70°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOIC
UC3852DTR FAQ
1.How can I place an order for UC3852DTR through Aetrix?
Please submit a Request for Quotation (RFQ) for UC3852DTR 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 UC3852DTR reliable?
The price and inventory of UC3852DTR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for UC3852DTR is usually 5 days.
3.What payment methods are accepted for UC3852DTR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for UC3852DTR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for UC3852DTR?
UC3852DTR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your UC3852DTR 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 UC3852DTR?
For technical support, including UC3852DTR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your UC3852DTR requirements.
6.How does Aetrix verify that UC3852DTR is sourced from the original manufacturer or authorized distributors?
All UC3852DTR 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 UC3852DTR meets industry standards.
7.What is the process for return or replacement of UC3852DTR?
All UC3852DTR units undergo pre-shipment inspection (PSI). If there is an issue with UC3852DTR, 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 UC3852DTR part is unused and in its original packaging.
Return procedure for UC3852DTR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
UC3852DTR 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…
