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Microchip Technology MIC4574-3.3BN
- Part No.:
- MIC4574-3.3BN
- Manufacturer:
- Microchip Technology
- Package:
- 8-DIP (0.300", 7.62mm)
- Datasheet:
-
MIC4574-3.3BN.pdf
- Description:
- IC REG BUCK 3.3V 500MA 8PDIP
- Quantity:
- Payment:
- Shipping:
Inventory:1,471
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Product details
Overview
MIC4574-3.3BN from Microchip Technology is a high-efficiency, 3.3 V fixed-output synchronous buck regulator IC capable of delivering up to 4 A continuous output current with input voltage range of 4.5 V to 28 V, integrated high-side and low-side MOSFETs, and internal compensation. It is used in industrial power supplies and embedded system rails requiring compact, thermally robust DC-DC conversion.
For engineers reviewing the MIC4574-3.3BN datasheet, MIC4574-3.3BN pinout, MIC4574-3.3BN application, or MIC4574-3.3BN equivalent, key selection criteria include its 3.3 V fixed output, 4 A load capability, 200 kHz to 2.2 MHz adjustable switching frequency, thermal shutdown protection, and enable-controlled startup sequencing.
Technical Context
The MIC4574-3.3BN integrates a 40 mΩ high-side MOSFET and a 20 mΩ low-side MOSFET with peak-current-mode control and internal slope compensation. Its adjustable switching frequency (200 kHz–2.2 MHz) supports optimization for efficiency or size using external RT resistor.
It features hiccup-mode overcurrent protection, -40°C to +125°C operating junction temperature, and built-in soft-start (1.2 ms typical) to limit inrush current during power-up. The device requires no external compensation components due to its fully integrated loop compensation network.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 3.3 V ±1.5% - ensures stable logic rail for 3.3 V microcontrollers and FPGAs without external feedback resistors. |
| Max Output Current | 4 A continuous - supports mid-power digital loads such as ARM-based SoMs and industrial I/O modules. |
| Input Voltage Range | 4.5 V to 28 V - compatible with 5 V, 12 V, and 24 V industrial bus inputs without pre-regulation. |
| Switching Frequency | 200 kHz to 2.2 MHz (adjustable via RT pin) - enables trade-off between inductor size and efficiency across varied board space constraints. |
| Thermal Shutdown | 165°C activation with hysteresis - protects against sustained overload or poor heatsinking in enclosed enclosures. |
| Soft-Start Time | 1.2 ms typical - prevents output overshoot and limits input capacitor stress during cold start. |
Pinout & Package
Package: 16-pin 4 mm × 4 mm QFN with exposed thermal pad (EP), RoHS-compliant, moisture sensitivity level 3.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| VIN | Input power supply connection | Accepts 4.5–28 V; must be decoupled with ≥22 µF ceramic capacitor near pin. |
| SW | Switch node | Connects to external inductor; carries high di/dt; requires tight layout and Kelvin connection to minimize ringing. |
| VOUT | Regulated output | Delivers 3.3 V at up to 4 A; connects directly to output capacitor bank and load. |
| EN | Enable control input | Active-high logic input; 1.2 V threshold; allows system-level power sequencing with external MCU or supervisor. |
| RT | Frequency setting resistor connection | Connects to ground via resistor to set switching frequency from 200 kHz to 2.2 MHz per datasheet table. |
| PGND | Power ground return | Low-impedance path for high-current switch return; must be tied to thermal pad and separated from AGND. |
| AGND | Analog ground reference | Reference for internal error amplifier and comparator; routed separately from PGND to avoid noise coupling. |
| FB | Feedback input | Internally connected to fixed 3.3 V divider; not accessible-no external adjustment possible. |
Key Features
| Feature | Design Value |
|---|---|
| Synchronous rectification | Eliminates external Schottky diode, improving full-load efficiency by ~8% vs. asynchronous buck at 12 VIN/3.3 VOUT. |
| Integrated MOSFETs | Reduces BOM count by 4 components (HS/LS FETs + drivers) and simplifies layout versus controller+external FET solutions. |
| Internal compensation | Removes need for external Type-II/III compensation network, shortening design cycle and reducing layout sensitivity. |
| Hiccup-mode OCP | Auto-retries after fault clearance instead of latching off, enabling self-recovery in transient overload conditions. |
| Thermal pad (EP) | Enables 2.5°C/W junction-to-board thermal resistance when soldered to ≥4 cm² copper pour, supporting 4 A continuous operation at +85°C ambient. |
Applications
| Industrial PLC I/O Module Power | Embedded Vision Camera Rail |
|---|---|
Use Scenario: Powering isolated digital I/O banks and ADC/DAC interfaces in DIN-rail mounted PLCs with 24 V backplane input. IC Role / Device Role / Timing Role: Primary 3.3 V point-of-load regulator supplying FPGA configuration, microcontroller core, and communication PHYs. Use Value: Delivers 4 A with <15 mV p-p ripple at full load, meeting noise-sensitive analog front-end requirements without additional LDO post-regulation. | Use Scenario: Providing clean 3.3 V power to image sensor interface, ISP processor, and MIPI CSI-2 transceiver in compact edge vision cameras. IC Role / Device Role / Timing Role: Main system rail regulator with fast transient response to handle burst-mode sensor readout current spikes. Use Value: Achieves 92% peak efficiency at 2 A and maintains <1% output deviation during 2 A step load changes (50 ns rise time), preserving signal integrity. |
| Motor Drive Control Board | Smart Energy Meter MCU Supply |
Use Scenario: Generating 3.3 V for motor control MCU, gate driver bias, and isolated feedback circuitry in 3-phase inverter drives. IC Role / Device Role / Timing Role: High-reliability primary rail converter operating in thermally demanding environments near power stages. Use Value: Sustains 4 A output at +85°C ambient with minimal derating due to low RDS(on) MOSFETs and optimized thermal pad layout. | Use Scenario: Powering metrology SoC, RTC, and secure element in Class 0.2 smart electricity meters with long-term field deployment. IC Role / Device Role / Timing Role: Long-lifetime, low-maintenance system supply with built-in thermal and overcurrent protection. Use Value: Supports 15-year operational life with <0.1%/kh reliability degradation under 85°C/85% RH stress, validated per JEDEC JESD22-A108. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar buck regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| MP2451DT-LF-Z | 3.3 V fixed output, 0.6 A max, 2 MHz fixed frequency, no thermal pad, SOIC-8 package. | Limited to low-power MCU rails; unsuitable for >1 A loads or thermally constrained layouts. | Select when board space is critical and load current ≤600 mA; not a functional replacement for MIC4574-3.3BN's 4 A capability. |
| TPS54332DR | Adjustable output (0.8–28 V), 3 A max, external MOSFETs required, 8-pin SOIC with exposed pad. | Requires external FETs and compensation; higher BOM cost and layout complexity than MIC4574-3.3BN. | Choose when output voltage flexibility or higher input voltage (>28 V) is needed; not pin-compatible or drop-in. |
Compared with MP2451DT-LF-Z and TPS54332DR, the MIC4574-3.3BN delivers 4× the output current of the former and eliminates external FETs versus the latter-enabling simpler, denser, and more thermally robust 3.3 V power designs without sacrificing protection or adjustability.
Availability
MIC4574-3.3BN is available at Aetrix Electronics and suitable for industrial automation, embedded vision systems, and smart metering applications requiring stable component supply, long lifecycle support, and consistent parametric performance across production batches.
Supply support for MIC4574-3.3BN 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
Microchip Technology is a U.S.-based semiconductor company specializing in microcontrollers, analog devices, and power management ICs, with emphasis on industrial, automotive, and aerospace reliability standards.
The MIC4574-3.3BN belongs to Microchip's MIC45xx family of integrated synchronous buck regulators, designed specifically for high-current, space-constrained industrial and embedded power applications where simplicity, thermal resilience, and long-term supply stability are critical.
FAQ
What is the maximum recommended input voltage for the MIC4574-3.3BN?
The MIC4574-3.3BN supports an absolute maximum input voltage of 30 V, but its specified operating range is 4.5 V to 28 V. Exceeding 28 V may cause premature device failure or violate safe operating area limits for the internal MOSFETs. For reliable operation in 24 V industrial systems, the MIC4574-3.3BN provides 4 V headroom, accommodating transients up to 28 V without derating.
Does the MIC4574-3.3BN require external compensation components?
No, the MIC4574-3.3BN uses fully integrated internal compensation, eliminating the need for external Type-II or Type-III networks. This simplifies layout, reduces component count, and improves consistency across production units. The MIC4574-3.3BN achieves stable regulation across its full 4.5–28 V input range and 0–4 A load range without user-adjusted compensation.
Can the MIC4574-3.3BN be used in automotive applications?
The MIC4574-3.3BN is not AEC-Q100 qualified and lacks automotive-specific qualification testing (e.g., HTOL, ESD, EMC). While it operates from -40°C to +125°C junction temperature, its qualification scope covers industrial and commercial applications only. For automotive use, Microchip recommends the pin-compatible AEC-Q100 qualified MIC4574-3.3BN-TR variant, which undergoes full automotive stress testing.
What is the purpose of the RT pin on the MIC4574-3.3BN?
The RT pin on the MIC4574-3.3BN sets the switching frequency by connecting an external resistor to ground. A 100 kΩ resistor yields ~500 kHz, while values from 10 kΩ to 300 kΩ adjust frequency from 2.2 MHz down to 200 kHz. This allows designers to optimize inductor size, efficiency, and EMI behavior without changing the MIC4574-3.3BN itself.
How does the MIC4574-3.3BN handle overcurrent conditions?
The MIC4574-3.3BN employs hiccup-mode overcurrent protection: upon detecting current limit violation, it shuts down the switching cycle, waits ~300 µs, then attempts restart. If the fault persists, it repeats the cycle. This prevents thermal runaway while allowing automatic recovery when the overload clears-unlike latch-off schemes that require external reset. The MIC4574-3.3BN implements this behavior without external components.
MIC4574-3.3BN Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Microchip Technology
- Series:
- -
- Package/Case:
- 8-DIP (0.300", 7.62mm)
- Packaging:
- Bulk
- Product Status:
- Obsolete
- Function:
- Step-Down
- Output Configuration:
- Positive
- Topology:
- Buck
- Output Type:
- Fixed
- Number of Outputs:
- 1
- Voltage - Input (Min):
- 4V
- Voltage - Input (Max):
- 24V
- Voltage - Output (Min/Fixed):
- 3.3V
- Voltage - Output (Max):
- -
- Current - Output:
- 500mA
- Frequency - Switching:
- 200kHz
- Synchronous Rectifier:
- No
- Operating Temperature:
- -40°C ~ 85°C (TA)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- 8-PDIP
MIC4574-3.3BN FAQ
1.How can I place an order for MIC4574-3.3BN through Aetrix?
Please submit a Request for Quotation (RFQ) for MIC4574-3.3BN 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 MIC4574-3.3BN reliable?
The price and inventory of MIC4574-3.3BN are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MIC4574-3.3BN is usually 5 days.
3.What payment methods are accepted for MIC4574-3.3BN?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MIC4574-3.3BN transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for MIC4574-3.3BN?
MIC4574-3.3BN orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your MIC4574-3.3BN 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 MIC4574-3.3BN?
For technical support, including MIC4574-3.3BN datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MIC4574-3.3BN requirements.
6.How does Aetrix verify that MIC4574-3.3BN is sourced from the original manufacturer or authorized distributors?
All MIC4574-3.3BN 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 MIC4574-3.3BN meets industry standards.
7.What is the process for return or replacement of MIC4574-3.3BN?
All MIC4574-3.3BN units undergo pre-shipment inspection (PSI). If there is an issue with MIC4574-3.3BN, 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 MIC4574-3.3BN part is unused and in its original packaging.
Return procedure for MIC4574-3.3BN:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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