My Inquiry
My Account
Monolithic Power Systems Inc. MP8666DN-LF
- Part No.:
- MP8666DN-LF
- Manufacturer:
- Monolithic Power Systems Inc.
- Category:
- DC DC Switching Controllers
- Package:
- 8-SOIC (0.154", 3.90mm Width) Exposed Pad
- Datasheet:
-
MP8666DN-LF.pdf
- Description:
- IC REG CTRLR BUCK 8SOIC
- Quantity:
- Payment:
- Shipping:
Inventory:3,226
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
MP8666DN-LF from Monolithic Power Systems is a synchronous step-down DC/DC converter with integrated 45mΩ high-side MOSFET and external low-side gate driver, delivering 6A continuous output current across 4.5V–21V input range. It operates at fixed 600kHz (synchronizable up to 1.5MHz), features cycle-by-cycle overcurrent protection with hiccup mode, thermal shutdown at 150°C, and supports adjustable output down to 0.8V - used in flat-panel TV power rails and broadband communication point-of-load regulation.
For engineers reviewing the MP8666DN-LF datasheet, MP8666DN-LF pinout, MP8666DN-LF application, or MP8666DN-LF equivalent, key selection criteria include its synchronizable gate driver architecture, 6A load capability with external MOSFET control, SOIC8E thermally enhanced package, and feedback voltage accuracy of ±2.5% (0.788V–0.828V) for precision output regulation.
Technical Context
The MP8666DN-LF implements fixed-frequency peak-current-mode control with internal 0.8V reference and error amplifier driving COMP node for loop stability. Its oscillator operates at 600kHz nominal with foldback frequency (60–240kHz) triggered when FB < 250mV during fault conditions.
It integrates a 5V internal VCC regulator powered from VIN, biasing the gate driver and analog circuitry; the bootstrap driver (BST pin) supplies floating gate voltage for the external low-side MOSFET, with UVLO (2.2V rising threshold) and internal charge pump regulation via D1/M3/C4.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Input Voltage Range | 4.5V to 21V - supports wide industrial and telecom input rails without pre-regulation. |
| Output Current | 6A continuous - enables single-chip PoL for mid-power digital loads like SoC cores or FPGAs. |
| Switching Frequency | 600kHz fixed, synchronizable 300kHz–1.5MHz - allows EMI tuning and multi-rail synchronization. |
| Feedback Voltage | 0.808V ±2.5% - sets output accuracy; enables 1.8V–5V outputs using standard resistor dividers. |
| High-Side RDS(on) | 45mΩ - limits conduction loss at 6A, enabling >95% efficiency with optimized external MOSFET. |
| Current Limit Threshold | 7.5A–8.0A - provides robust short-circuit protection while allowing transient headroom above 6A rating. |
| Thermal Shutdown | 150°C with 10°C hysteresis - ensures safe operation under sustained overload or poor PCB thermal design. |
Pinout & Package
MP8666DN-LF is housed in an 8-pin SOIC package with exposed thermal pad (SOIC8E), optimized for surface-mount assembly and thermal dissipation on 4-layer PCBs (θJA = 50°C/W).
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 SW | Switch Node Output | Connects to inductor and external low-side MOSFET source; carries high di/dt switching current. |
| 2 BST | Bootstrap Capacitor Terminal | Forms floating supply for gate driver; requires 0.1–1µF ceramic cap between BST and SW. |
| 3 VCC | Internal Regulator Bias Supply | Decoupled with 1µF X7R/X5R capacitor; powers gate driver and analog blocks from VIN. |
| 4 BG | Gate Driver Output | Drives gate of external synchronous MOSFET; sink/source impedances 1Ω/4Ω enable fast turn-on/off. |
| 5 GND | Analog & Power Ground Reference | Reference for FB and error amplifier; must be isolated from high-current return paths to avoid noise coupling. |
| 6 FB | Feedback Input | Senses output voltage via resistor divider; internal 0.8V reference enables precise output regulation. |
| 7 EN/SYNC | Enable Control & Clock Sync Input | Pull high ≥1.2V to enable; accept external 300kHz–1.5MHz clock for EMI reduction or multi-phase sync. |
| 8 IN | Main Power Input | Accepts 4.5V–21V unregulated supply; requires local 22µF ceramic input capacitor for surge suppression. |
Key Features
| Feature | Design Value |
|---|---|
| Synchronizable Gate Driver | Enables coordinated switching across multiple MP8666DN-LF units or with other converters to minimize system-level EMI peaks. |
| Cycle-by-Cycle Overcurrent Protection | Prevents MOSFET destruction during startup or short-circuit by limiting peak inductor current to 7.5–8.0A per cycle. |
| Hiccup-Mode Fault Recovery | Reduces average short-circuit current and die temperature by periodically restarting after FB drops below 0.56V. |
| Stable with Low-ESR Ceramic Capacitors | Eliminates need for electrolytic or tantalum output caps; supports compact, high-reliability designs using X5R/X7R ceramics. |
| Integrated VCC Regulator | Provides regulated 4.5–5V bias from VIN across full input range, reducing external component count and improving startup robustness. |
Applications
| Flat Panel Television Power Rails | Digital Set-Top Box Core Supply |
|---|---|
|
Use Scenario: Providing stable 3.3V/5V rails for LCD panel timing controllers and video processing ASICs. IC Role / Device Role / Timing Role: Primary synchronous buck regulator delivering 6A continuous current with tight line/load regulation. Use Value: Enables single-chip solution replacing discrete controller + external MOSFETs, reducing BOM count and layout area by >30%. |
Use Scenario: Generating 1.8V core voltage for MPEG decoder SoCs under dynamic load transients. IC Role / Device Role / Timing Role: High-efficiency point-of-load regulator with 600kHz switching and fast current-mode response. Use Value: Maintains output ripple <15mV under 6A load steps, meeting SoC voltage tolerance requirements without additional LDO post-regulation. |
| Broadband Communications Equipment | Personal Video Recorder (PVR) Storage Interface |
|
Use Scenario: Powering Ethernet PHYs and packet processors in cable modems and DSLAM line cards. IC Role / Device Role / Timing Role: Synchronized buck converter operating at 1.2MHz to avoid interference with 10/100/1000BASE-T signaling bands. Use Value: Achieves >92% efficiency at 5V/4A output while meeting CISPR-22 Class B conducted EMI limits via frequency synchronization. |
Use Scenario: Supplying 2.5V to SATA controller ICs and flash memory buffers during burst write operations. IC Role / Device Role / Timing Role: High-current buck with hiccup-mode protection prevents thermal runaway during sustained 6A storage I/O bursts. Use Value: Eliminates need for external thermal monitoring circuitry; device self-recovers after transient overload without system reset. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar synchronous buck controller applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MPQ8666GL-10-Z | Automotive-grade AEC-Q100 qualified version; same electrical specs but rated –40°C to +125°C junction. | Required for automotive infotainment head units where ambient exceeds +85°C. | Select when extended temperature range and automotive qualification are mandatory; otherwise MP8666DN-LF offers lower cost. |
| LM5116MH/NOPB | External high-/low-side MOSFET controller (no integrated switch); supports up to 12A with higher VIN max (100V). | Suitable for industrial 48V input systems where MP8666DN-LF's 21V max input is insufficient. | Choose LM5116MH/NOPB only if input voltage exceeds 21V or >6A output is required; adds complexity and external FET cost. |
Compared with MPQ8666GL-10-Z, the MP8666DN-LF trades automotive qualification for cost and availability in commercial applications; versus LM5116MH/NOPB, it delivers simpler, lower-component-count 6A solutions at the expense of input voltage and current scalability.
Availability
MP8666DN-LF is available at Aetrix Electronics and suitable for flat-panel television power rails, digital set-top box core supplies, and broadband communications equipment requiring stable component supply, RoHS-compliant packaging, and long-term production continuity.
Supply support for MP8666DN-LF 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
Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance analog and mixed-signal ICs for power management, motion control, and interface applications.
The MP8666 belongs to MPS's high-current synchronous buck controller product line, designed specifically for space-constrained, high-efficiency point-of-load conversion in consumer and communications equipment.
FAQ
What is the minimum recommended input capacitance for MP8666DN-LF at 6A output?
A 22µF X5R or X7R ceramic capacitor is specified for 6A applications to suppress input surge current and high-frequency switching noise. This value assumes typical board layout; larger capacitance may be needed if input source impedance exceeds 50mΩ at 600kHz.
Can MP8666DN-LF operate without an external bootstrap diode?
Yes - the internal bootstrap charging circuit (D1/M3/C4) supports duty cycles up to ~65%. An external IN4148 diode is optional only when VOUT/VIN > 0.65 to improve efficiency and BST voltage stability under high-duty-cycle conditions.
How does the hiccup-mode overcurrent protection behave during sustained short-circuit?
When FB falls below 250mV, the oscillator frequency folds back and the device enters hiccup mode: it attempts restart every ~10ms, limiting average short-circuit current to ~1.2A and die temperature to <120°C until fault removal.
What is the maximum allowable PCB copper area for the exposed pad on SOIC8E?
The exposed pad must be soldered to a solid copper thermal pad ≥12mm² (e.g., 3mm × 4mm) with ≥4 thermal vias (0.3mm diameter) connecting to inner ground planes. Excessive copper beyond this provides diminishing thermal returns and risks solder wicking.
Is the MP8666DN-LF pin-compatible with earlier MP8666 revisions?
Yes - MP8666DN-LF uses the same SOIC8E package and pinout as all MP8666 variants (including MP8666DN). The "-LF" suffix denotes lead-free/RoHS-compliant finish; electrical and thermal specifications remain identical to Rev. 1.21.
What feedback resistor values set a 2.5V output voltage?
Using R1 = 40.2kΩ (1%), R2 = 19.1kΩ (1%) yields VOUT = 0.808V × (1 + 40.2kΩ/19.1kΩ) ≈ 2.5V. These values match Table 1 in the datasheet and optimize loop bandwidth for transient response.
Does MP8666DN-LF require external compensation components?
No - the MP8666DN-LF features an optimized internal compensation network. Only the external R1/R2 feedback divider and input/output capacitors are required; no external RC or type-II/III compensation network is needed.
MP8666DN-LF Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Monolithic Power Systems Inc.
- Series:
- -
- Package/Case:
- 8-SOIC (0.154", 3.90mm Width) Exposed Pad
- Packaging:
- Tube
- 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):
- 4.5V ~ 21V
- Frequency - Switching:
- 600kHz
- Duty Cycle (Max):
- 90%
- Synchronous Rectifier:
- No
- Clock Sync:
- Yes
- Serial Interfaces:
- -
- Control Features:
- Enable
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 8-SOICE
MP8666DN-LF FAQ
1.How can I place an order for MP8666DN-LF through Aetrix?
Please submit a Request for Quotation (RFQ) for MP8666DN-LF 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 MP8666DN-LF reliable?
The price and inventory of MP8666DN-LF are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MP8666DN-LF is usually 5 days.
3.What payment methods are accepted for MP8666DN-LF?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MP8666DN-LF transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MP8666DN-LF?
MP8666DN-LF orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MP8666DN-LF 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 MP8666DN-LF?
For technical support, including MP8666DN-LF datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MP8666DN-LF requirements.
6.How does Aetrix verify that MP8666DN-LF is sourced from the original manufacturer or authorized distributors?
All MP8666DN-LF 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 MP8666DN-LF meets industry standards.
7.What is the process for return or replacement of MP8666DN-LF?
All MP8666DN-LF units undergo pre-shipment inspection (PSI). If there is an issue with MP8666DN-LF, 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 MP8666DN-LF part is unused and in its original packaging.
Return procedure for MP8666DN-LF:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
MP8666DN-LF 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
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…
LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…
Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…
Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.
18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…
Hall effect sensor guide covering working principle, linear and digital sensors, Arduino circuits, current sensing, speed detection, automotive applications, A3144 examples, signal filtering and datash…
Product Change Notification guide for electronic components, covering PCN meaning, PCN vs PDN/EOL, common change types, risk levels, form-fit-function review, engineering validation, BOM control, LTB/L…
A practical guide to blend door actuators, covering HVAC function, symptoms, location, AC and heater issues, reset and calibration, replacement cost, electrical diagnosis, compatibility checks, and rep…
Engineering guide to Raspberry Pi alternatives, covering chip-level differences, Orange Pi, ROCK, Jetson, Banana Pi, NanoPi, Compute Module, Pico, GPIO, camera, HAT compatibility, and replacement risks…
