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onsemi NCP5666DS50R4G
- Part No.:
- NCP5666DS50R4G
- Manufacturer:
- onsemi
- Package:
- TO-263-6, D2PAK (5 Leads + Tab), TO-263BA
- Datasheet:
-
NCP5666DS50R4G.pdf
- Description:
- IC REG LINEAR 5V 3A D2PAK-5
- Quantity:
- Payment:
- Shipping:
Inventory:3,434
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Product details
Overview
NCP5666DS50R4G from onsemi is a 5.0 V, 3.0 A low dropout linear regulator in D2PAK package with enable control, ±1% output voltage accuracy, ultra-fast transient response (1–3 µs), and thermal/current protection-designed for post-regulation in high-current server and ASIC power supplies.
For engineers reviewing the NCP5666DS50R4G datasheet, pinout, applications, or equivalent options, this page delivers verified electrical specs, thermal performance data, real-world stability conditions with ceramic/tantalum/aluminum capacitors, and validated alternative options for 5 V/3 A LDO replacement scenarios.
Technical Context
The NCP5666DS50R4G implements a fixed-output, internally compensated LDO architecture with a 0.9 V reference and resistor-divider feedback network (R1/R2) setting Vout = 5.0 V. Its low ground current (≤3.0 mA at 3.0 A load) remains independent of output current, enabling predictable thermal behavior under full load.
It features integrated enable logic with 1.3 V turn-on threshold and 0.3 V turn-off threshold, current limiting clamped at 4.5 A, and thermal shutdown activation at 160 °C. Ripple rejection exceeds 65 dB at 1 kHz and 70 dB at 120 Hz, supporting clean power delivery in noise-sensitive digital loads.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | 5.00 V ±1% (2.475–5.100 V over temp/load, ensuring tight regulation for 5 V logic rails) |
| Maximum Output Current | 3.0 A continuous (supports high-power FPGA/ASIC core or I/O rail regulation) |
| Dropout Voltage | 1.0 V typical at 3.0 A (enables operation with Vin ≥ 6.0 V, minimizing power loss) |
| Ground Current | ≤3.0 mA at 3.0 A load (low quiescent loss improves efficiency at full load) |
| Ripple Rejection | ≥65 dB at 1 kHz (suppresses switching noise from upstream DC-DC converters) |
| Output Noise | 57 µVrms (10 Hz–100 kHz, suitable for analog-sensitive circuits without bypass cap) |
| Enable Threshold | VEN(HI) = 1.3 V, VEN(LO) = 0.3 V (compatible with 3.3 V and 5 V logic control signals) |
| Thermal Shutdown | 160 °C junction temperature (protects against sustained overload or poor heatsinking) |
Pinout & Package
D2PAK (Case 936A) thermally enhanced surface-mount package with exposed tab (Pin 3/Tab = GND) for direct PCB thermal coupling; 5-pin layout optimized for high-current routing and thermal dissipation.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - Vin | Positive input supply | Accepts 6.5–7.0 V for 5.0 V output; absolute max 18 V (transient), recommended operating ≤9 V |
| 2 - EN | Enable control input | Logic-high (>1.3 V) enables regulation; logic-low (<0.3 V) disables output and reduces disable current to ≤300 µA |
| 3 / Tab - GND | Power ground return | Primary thermal path; must be connected to large copper area (650 mm² minimum) for RθJA = 45 °C/W |
| 4 - NC | No-connect terminal | Internally unconnected; PCB traces permitted but no electrical function |
| 5 - Vout | Regulated output | Delivers stable 5.0 V ±1% to load; requires 2.2–220 µF output capacitor (ceramic/tantalum/aluminum) |
Key Features
| Feature | Design Value |
|---|---|
| ±1% output voltage accuracy | Ensures compliance with 5 V TTL/CMOS interface tolerances across -40°C to +85°C ambient |
| Ultra-fast transient response (1–3 µs) | Maintains <50 mV output deviation during 10 mA ↔ 3.0 A load steps, critical for burst-mode processors |
| Stable with ceramic, tantalum & aluminum caps | Eliminates need for capacitor type qualification; supports low-ESR ceramics down to 2.2 µF |
| Low noise without bypass capacitor | 57 µVrms noise enables clean analog supply without extra 10 nF bypass cap |
| Enable function with low disable current | Reduces system standby power: IDIS ≤300 µA at 5 V output, enabling efficient power sequencing |
| Integrated current & thermal protection | Clamps peak current to 4.5 A and shuts down at 160 °C-prevents damage during short-circuit or thermal runaway |
Applications
| Server Power Rails | ASIC Core Supply |
|---|---|
Use Scenario: Post-regulation of 12 V intermediate bus to deliver clean 5 V to memory buffers and PCIe switch I/O banks. IC Role / Device Role / Timing Role: Final-stage LDO providing low-noise, fast-transient 5 V power with enable-controlled sequencing. Use Value: 57 µVrms noise and 1–3 µs settling prevent signal integrity degradation on high-speed serial links. |
Use Scenario: Local regulation for ASIC auxiliary I/O banks requiring tightly regulated 5 V at up to 3.0 A. IC Role / Device Role / Timing Role: High-current LDO with thermal foldback, enabling safe operation under dynamic load bursts. Use Value: 1.0 V dropout at 3.0 A minimizes power loss and heat generation compared to higher-VDO alternatives. |
| Networking Equipment | Gaming/STB Modules |
Use Scenario: Powering 5 V PHY interfaces and management controllers in 1U switches with constrained airflow. IC Role / Device Role / Timing Role: Thermally robust LDO with D2PAK package and RθJC = 5.0 °C/W for direct heatsink mounting. Use Value: 45 °C/W RθJA (with 650 mm² copper) sustains 3.0 A output at +85°C ambient without derating. |
Use Scenario: Enabling/disabling 5 V subsystems (e.g., HDMI audio processor, USB hub) via microcontroller GPIO. IC Role / Device Role / Timing Role: Enable-controlled LDO supporting low-power sleep modes with ≤300 µA disable current. Use Value: Logic-compatible EN pin (1.3 V/0.3 V thresholds) eliminates level-shifter requirements in 3.3 V MCU designs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar 5 V/3 A LDO applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS7A4701RGWR | Lower noise (4.7 µVrms), lower IQ (1 mA), but only 1 A output and SOIC-20 package | Not suitable for 3 A loads; requires parallel devices or redesign for current capacity | Select only if ultra-low noise dominates over current capability and board space permits larger footprint |
| MCP1826T-5002E/OT | Same 5 V/3 A rating, SOT-223 package, but higher dropout (1.3 V typ), no enable, and ±2% accuracy | Lacks enable control and tighter regulation; unsuitable for sequenced or precision 5 V rails | Consider only for cost-sensitive, non-sequenced, non-critical 5 V applications where D2PAK thermal performance is unnecessary |
Compared with TPS7A4701RGWR and MCP1826T-5002E/OT, the NCP5666DS50R4G uniquely delivers 3.0 A output, ±1% accuracy, enable functionality, and D2PAK thermal performance in a single device-making it the only drop-in solution for high-current, sequenced, precision 5 V LDO requirements.
Availability
NCP5666DS50R4G is available at Aetrix Electronics and suitable for server power rails, ASIC I/O supplies, and networking equipment requiring stable component supply, long-term lifecycle support, and Pb-free compliance.
Supply support for NCP5666DS50R4G 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
onsemi (formerly ON Semiconductor) is a global semiconductor supplier delivering energy-efficient silicon solutions for automotive, industrial, cloud, and IoT applications.
The NCP5666DS50R4G belongs to onsemi's high-current LDO family, engineered specifically for post-regulation in high-density computing systems where thermal robustness, fast transient response, and precision voltage stability are critical.
FAQ
What is the maximum input voltage for the NCP5666DS50R4G?
The NCP5666DS50R4G has an absolute maximum input voltage of 18 V, but its recommended operating input range is 6.5 V to 7.0 V for 5.0 V output. Operation above 9 V requires strict thermal management to avoid exceeding power dissipation limits, as specified in the Thermal Consideration section of the datasheet. The NCP5666DS50R4G is not rated for continuous operation at 12 V or 15 V inputs without significant derating.
Does the NCP5666DS50R4G require an external bypass capacitor for low-noise operation?
No, the NCP5666DS50R4G achieves 57 µVrms output noise (10 Hz–100 kHz) without any external bypass capacitor, as confirmed in the Electrical Characteristics table. This design eliminates the need for a dedicated 10 nF ceramic bypass cap typically required by other LDOs-reducing BOM count and PCB area while maintaining clean 5 V supply for noise-sensitive analog circuitry.
Can the NCP5666DS50R4G be used with ceramic output capacitors?
Yes, the NCP5666DS50R4G is explicitly characterized and guaranteed stable with ceramic, tantalum, and aluminum electrolytic capacitors ranging from 2.2 µF to 220 µF. Figure 12 in the datasheet defines the stable ESR region for each capacitor type, confirming compatibility with low-ESR X7R/X5R ceramics commonly used in high-density layouts.
What is the thermal resistance and heatsinking requirement for the NCP5666DS50R4G?
The NCP5666DS50R4G in D2PAK package has RθJA = 45 °C/W when mounted on a 650 mm² copper area (1 oz thickness), and RθJC = 5.0 °C/W to the tab. To sustain 3.0 A at +85°C ambient, the PCB must provide adequate copper area and/or optional heatsink attachment to the exposed tab-failure to meet this requirement risks thermal shutdown activation at 160 °C junction temperature.
Is the NCP5666DS50R4G pin-compatible with other manufacturers' 5 V/3 A LDOs?
The NCP5666DS50R4G is explicitly stated in its datasheet to be pin-compatible with a Semtech device (exact part unspecified), but no cross-manufacturer pin-to-pin replacements are documented. Substitution with non-onsemi parts requires full validation of pin function mapping, thermal pad connection, enable logic thresholds, and transient response-especially given its unique D2PAK 5-pin layout with NC pin and tab-as-GND configuration.
NCP5666DS50R4G Specifications
- Product attributes
- Attribute value
- Manufacturer:
- onsemi
- Series:
- -
- Package/Case:
- TO-263-6, D2PAK (5 Leads + Tab), TO-263BA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Output Configuration:
- Positive
- Output Type:
- Fixed
- Number of Regulators:
- 1
- Voltage - Input (Max):
- 9V
- Voltage - Output (Min/Fixed):
- 5V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 1.3V @ 3A
- Current - Output:
- 3A
- Current - Quiescent (Iq):
- 3 mA
- Current - Supply (Max):
- -
- PSRR:
- 70dB ~ 65dB (120Hz ~ 1kHz)
- Control Features:
- Enable
- Protection Features:
- Over Current, Over Temperature
- Operating Temperature:
- -40°C ~ 85°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- D2PAK-5
NCP5666DS50R4G FAQ
1.How can I place an order for NCP5666DS50R4G through Aetrix?
Please submit a Request for Quotation (RFQ) for NCP5666DS50R4G 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 NCP5666DS50R4G reliable?
The price and inventory of NCP5666DS50R4G are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for NCP5666DS50R4G is usually 5 days.
3.What payment methods are accepted for NCP5666DS50R4G?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for NCP5666DS50R4G transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for NCP5666DS50R4G?
NCP5666DS50R4G orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your NCP5666DS50R4G 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 NCP5666DS50R4G?
For technical support, including NCP5666DS50R4G datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your NCP5666DS50R4G requirements.
6.How does Aetrix verify that NCP5666DS50R4G is sourced from the original manufacturer or authorized distributors?
All NCP5666DS50R4G 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 NCP5666DS50R4G meets industry standards.
7.What is the process for return or replacement of NCP5666DS50R4G?
All NCP5666DS50R4G units undergo pre-shipment inspection (PSI). If there is an issue with NCP5666DS50R4G, 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 NCP5666DS50R4G part is unused and in its original packaging.
Return procedure for NCP5666DS50R4G:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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