MCP19123T-E/MQ Microchip Integrated Circuit (Quad Flat No-Lead) In Stock
Microchip MCP19123T-E/MQ is a current-mode PWM switching controller accepting a 4.5 V to 40 V input range with optional 3 V to 5 V regulated output. It uses analog current-mode PWM control for fast transient response and accurate cycle-by-cycle current limiting. Packaged in a 28-pin QFN for compact power supply designs with 7-week lead time.
- Manufacturer
- Microchip
- Package
- Quad Flat No-Lead
- Pin Count
- 28
- Lifecycle
- ACTIVE
- Datasheet
- MCP19123T-E/MQ Datasheet PDF
- Category
- Integrated Circuit
- Price
- From $4.1200(MOQ 1)
- Temp Range
- -40.0°C to 125.0°C
- RoHS
- Compliant
- Lead Time
- 3–7 business days
- Shipping
- DHL Express · Worldwide
Key Features
- Current-mode PWM control with 4.5 V to 40 V input range enabling flexible DC-DC converter topologies
- Optional 3 V to 5 V regulated output for self-powered controller biasing without an external bias supply
- Cycle-by-cycle current limiting via analog current-mode control for robust overload protection
- 28-pin QFN package enabling high-density power supply layouts with exposed thermal pad for heat dissipation
Applications
MCP19123T-E/MQ is used in industrial and automotive power supply designs requiring a wide 4.5 V to 40 V input range with current-mode PWM regulation. Telecom and server power modules use it to implement synchronous buck or boost converters where fast load transient response and cycle-by-cycle overcurrent protection are essential. Its 3 V to 5 V bias output option simplifies controller self-powering in isolated and non-isolated converter designs.
Specifications
| Manufacturer Package Code | QFN-28 |
| Factory Lead Time | 7Weeks |
| Date Of Intro | 2017-05-05 |
| YTEOL | 18 |
| Additional Feature | 3V TO 5V REGULATING OUTPUT ALSO AVAILABLE |
| Analog IC - Other Type | SWITCHING CONTROLLER |
| Control Mode | CURRENT-MODE |
| Control Technique | PULSE WIDTH MODULATION |
| Input Voltage-Max | 40V |
| Input Voltage-Min | 4.5V |
| Input Voltage-Nom | 12V |
| JESD-30 Code | S-PQCC-N28 |
| JESD-609 Code | e3 |
| Number of Functions | 1 |
| Output Voltage-Max | 16V |
| Output Voltage-Min | 0.3V |
| Package Body Material | PLASTIC/EPOXY |
| Package Equivalence Code | LCC28,.2SQ,20 |
| Package Shape | SQUARE |
| Package Style | CHIP CARRIER, HEAT SINK/SLUG, VERY THIN PROFILE |
| Screening Level | TS 16949 |
| Surface Mount | YES |
| Switcher Configuration | BUCK |
| Switching Frequency-Max | 1600kHz |
| Temperature Grade | AUTOMOTIVE |
| Terminal Finish | Matte Tin (Sn) |
| Terminal Form | NO LEAD |
| Terminal Pitch | 0.5mm |
| Terminal Position | QUAD |
| Package | Quad Flat No-Lead |
Compliance & Regulatory
| RoHS Status | Compliant |
| Lead-Free | Yes (Pb-Free) |
| ECCN | EAR99 |
| HTS Code | 8542.39.00.01 |
| Country of Origin | Thailand |
Alternate & Equivalent Parts
Compatible alternatives and drop-in replacements for MCP19123T-E/MQ:
Switching Controller, Current-mode, 1600kHz Switching Freq-Max, PQCC28
Switching Controller, Current-mode, 1600kHz Switching Freq-Max, PQCC24
Frequently Asked Questions
What control mode does MCP19123T-E/MQ use, and how does this benefit overcurrent protection?
MCP19123T-E/MQ uses analog current-mode PWM control, which measures inductor current on a cycle-by-cycle basis and compares it to a programmable threshold. This provides inherent overcurrent limiting that immediately terminates the PWM pulse if current exceeds the set limit, without relying on slower fault detection circuits. In automotive and industrial applications with a 4.5 V to 40 V input, this prevents inductor saturation and switch damage during overload events faster than 1 µs response time.
How does the optional 3 V to 5 V regulated output of MCP19123T-E/MQ simplify converter design?
Many PWM controllers require an external bias supply derived from the main bus to power internal logic. MCP19123T-E/MQ's optional integrated 3 V to 5 V regulated output eliminates this external component, powering the controller itself from the 4.5 V to 40 V input bus. This reduces BOM count by removing an auxiliary winding or pre-regulator circuit, saving board space in the 28-pin QFN design and reducing startup complexity in isolated converter topologies.
In what input voltage range does MCP19123T-E/MQ operate, and which power supply architectures does this support?
MCP19123T-E/MQ operates from a 4.5 V to 40 V input, covering 12 V, 24 V, and 36 V industrial bus voltages used in factory automation, telecom equipment, and automotive 12 V or 24 V systems. This wide range makes it suitable for non-isolated buck converters, boost converters, and SEPIC topologies where the input may fluctuate significantly. The 40 V maximum also provides margin for load-dump transients in automotive 12 V designs.
How does the 28-pin QFN package of MCP19123T-E/MQ affect thermal performance in high-power converter designs?
The 28-pin QFN package includes an exposed thermal pad on its underside that transfers heat directly to the PCB copper pour, significantly lowering junction-to-ambient thermal resistance compared to leaded packages. In a well-designed 4-layer PCB with adequate copper fill, the controller can dissipate several hundred milliwatts of internal power while keeping junction temperature below 125°C at full 40 V input and maximum switching frequency. This enables high-density, thermally reliable power module designs without a heatsink.
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