Send an Inquiry

To receive a quote for your project, please fill in the following information, and we’ll get back to you promptly.

Submit Inventory List

Please fill in the following information, and we’ll get back to you promptly.

Home > Products > Integrated Circuits (ICs) > Power Management (PMIC) > Voltage Regulators - DC DC Switching Regulators

Microchip Technology MIC26903-ZAYJL-TR

Name: MIC26903-ZAYJL-TR
Brand: Microchip Technology
SKU: MIC26903-ZAYJL-TR
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

Compare

Part No.:: MIC26903-ZAYJL-TR

Manufacturer:: Microchip Technology

Category:: Voltage Regulators - DC DC Switching Regulators

Package:: 28-PowerVQFN

Datasheet:: MIC26903-ZAYJL-TR.pdf

Description:: IC REG BUCK ADJ 9A 28QFN

Quantity:: RFQ Add To RFQ list

Payment:

Shipping:

Inventory:4,973

Please send an inquiry. Send us your inquiry, and we will respond immediately.

Product details

Overview

MIC26903-ZAYJL-TR from Micrel is a synchronous DC-to-DC buck regulator with Hyper Speed Control™ architecture, delivering up to 9A output current across 4.5V–28V input range, adjustable 0.6V–5.5V output voltage, ±1% feedback accuracy, and 600kHz fixed switching frequency. It integrates high- and low-side MOSFETs (R_DS(ON) = 27mΩ / 10.5mΩ), operates from –40°C to +125°C, and targets point-of-load regulation in telecom infrastructure and embedded power systems.

For engineers reviewing the MIC26903-ZAYJL-TR datasheet, MIC26903-ZAYJL-TR pinout, MIC26903-ZAYJL-TR application, or MIC26903-ZAYJL-TR equivalent, key selection considerations include its adaptive on-time control for fast transient response, Any Capacitor® stability without external compensation, integrated Power Good (PG) output, and 28-pin 5mm × 6mm QFN package with thermal pad.

Technical Context

The MIC26903-ZAYJL-TR employs adaptive on-time control that estimates t_ON using V_OUT/V_IN ratio to maintain ~600kHz nominal frequency while enabling ultra-fast load transients. Its ripple-based triggering eliminates slope compensation and supports stable operation with zero-to-high ESR output capacitors.

Protection logic includes foldback current limiting (12.5–20A threshold), hiccup-mode short-circuit response, internal soft-start (5ms), undervoltage lockout on VDD (3.7–4.5V), and thermal shutdown at 160°C. The device uses internal R_DS(ON) sensing for current limit-no external sense resistor-and supports safe startup into pre-biased loads.

Key Specifications

Parameter	Value and Actual Design Meaning
Input Voltage Range	4.5V to 28V - supports wide-range industrial and telecom inputs including 12V, 24V rails.
Output Current	Up to 9A continuous - sufficient for FPGA core, ASIC, or multi-core processor POL supplies.
Output Voltage Range	Adjustable 0.6V to 5.5V - covers DDR memory, CPU cores, I/O, and analog subsystems.
Feedback Accuracy	±1% at 0°C–85°C - ensures tight regulation for sensitive digital loads.
Switching Frequency	600kHz (typ.) - balances efficiency, size, and EMI; tolerates ±25% variation over conditions.
Efficiency	95% peak - achieved at mid-load with 12V_IN/1.8V_OUT, minimizing thermal stress.
Junction Temp Range	–40°C to +125°C - qualified for extended-temperature industrial and networking equipment.
Package	28-pin 5mm × 6mm QFN with exposed thermal pad - enables high-power density and efficient heat transfer.

Pinout & Package

28-pin 5mm × 6mm QFN (JL) package with exposed thermal pad (pin 28 is VDD; pin 2 is PGND; pin 23 is SGND; pin 1 and 28 are internal LDO outputs; pin 20 is BST; pin 22 is CS; pin 24 is FB; pin 25 is PG; pin 26 is EN; pins 13–19 are PVIN; pins 4,9–12 are SW).

Pin/Terminal	Circuit Role	Design Meaning
PVIN (13–19)	High-side MOSFET drain input	Primary power input path; requires local ceramic bypassing to PGND for noise suppression.
SW (4,9–12)	Switch node	Connection between high-side source and low-side drain; high dv/dt node requiring minimized trace area and isolation.
BST (20)	Bootstrap supply	Drives high-side gate via 0.1µF capacitor to SW; Schottky diode required from PVDD to BST.
CS (22)	Current sense input	Monitors low-side MOSFET R_DS(ON) during OFF-time for foldback protection-requires Kelvin connection to SW.
FB (24)	Feedback input	Regulated to 0.6V reference; sets output via resistor divider; bias current <50nA enables high-impedance dividers.
PG (25)	Power Good open-drain	Asserts high when V_OUT ≥ 92% of nominal; requires external pull-up to VDD (≥10kΩ).
EN (26)	Enable control	CMOS-compatible; logic high enables regulation, low shuts down IC to 5µA quiescent current.
VDD (28)	Internal 5V LDO output	Supplies gate drivers and internal circuitry; must be bypassed with 1µF ceramic to SGND.

Key Features

Feature	Design Value
Hyper Speed Control™ architecture	Enables <1µs transient recovery and supports high VIN/low VOUT ratios (e.g., 28V→0.6V) without instability.
Any Capacitor® stability	Operates stably with ceramic, polymer, or electrolytic output caps-no ESR dependency or external compensation needed.
Integrated MOSFETs	27mΩ high-side and 10.5mΩ low-side R_DS(ON) reduce conduction loss and simplify layout vs. controller-only solutions.
Pre-biased startup support	Allows safe turn-on when output rail is already charged-critical for hot-swap and redundant power systems.
Thermal and fault protection	Includes hiccup-mode short-circuit response, foldback current limit, UVLO, and 160°C thermal shutdown with 15°C hysteresis.

Applications

Distributed POL in Telecom Infrastructure	Graphics & Video Card Power
Use Scenario: Regulating 12V or 24V backplane to multiple low-voltage rails (e.g., 1.2V GPU core, 1.8V memory, 3.3V I/O) in 5G baseband units or optical line terminals. IC Role / Device Role / Timing Role: Primary synchronous buck regulator providing isolated, high-current POL conversion with fast transient response to handle bursty data traffic loads. Use Value: Hyper Speed Control™ reduces required output capacitance by >40% versus conventional buck regulators, saving board space and cost in dense telecom modules.	Use Scenario: Delivering tightly regulated 0.8V–1.2V at up to 9A to GPU cores on PCIe graphics cards, where rapid load steps occur during rendering or compute workloads. IC Role / Device Role / Timing Role: High-efficiency, high-bandwidth DC-DC converter managing dynamic voltage scaling and load-line regulation under sub-microsecond transients. Use Value: ±1% feedback accuracy and 600kHz switching ensure stable core voltage during DVFS transitions, preventing timing violations in high-clock-rate GPUs.
Set-Top Box & Gateway SoC Power	Industrial Embedded Controller Rails
Use Scenario: Generating 1.0V, 1.2V, and 1.8V rails for ARM-based SoCs in residential gateways, where standby power and thermal management are critical. IC Role / Device Role / Timing Role: Main SoC core regulator with enable-controlled sequencing and Power Good signaling for system-level power management. Use Value: 5µA shutdown current and –40°C to +125°C operation allow reliable low-power standby and extended-temperature deployment in unventilated enclosures.	Use Scenario: Supplying 3.3V and 5.0V rails to microcontrollers, ADCs, and interface ICs in programmable logic controllers (PLCs) and motor drives operating in harsh factory environments. IC Role / Device Role / Timing Role: Robust, self-protected buck stage replacing discrete FET+controller designs to improve MTBF and reduce BOM count. Use Value: Integrated foldback current limit and thermal shutdown eliminate need for external fault monitoring circuits, simplifying safety-certified designs.

Distributed POL in Telecom Infrastructure

Graphics & Video Card Power

Use Scenario: Regulating 12V or 24V backplane to multiple low-voltage rails (e.g., 1.2V GPU core, 1.8V memory, 3.3V I/O) in 5G baseband units or optical line terminals.

IC Role / Device Role / Timing Role: Primary synchronous buck regulator providing isolated, high-current POL conversion with fast transient response to handle bursty data traffic loads.

Use Value: Hyper Speed Control™ reduces required output capacitance by >40% versus conventional buck regulators, saving board space and cost in dense telecom modules.

Use Scenario: Delivering tightly regulated 0.8V–1.2V at up to 9A to GPU cores on PCIe graphics cards, where rapid load steps occur during rendering or compute workloads.

IC Role / Device Role / Timing Role: High-efficiency, high-bandwidth DC-DC converter managing dynamic voltage scaling and load-line regulation under sub-microsecond transients.

Use Value: ±1% feedback accuracy and 600kHz switching ensure stable core voltage during DVFS transitions, preventing timing violations in high-clock-rate GPUs.

Set-Top Box & Gateway SoC Power

Industrial Embedded Controller Rails

Use Scenario: Generating 1.0V, 1.2V, and 1.8V rails for ARM-based SoCs in residential gateways, where standby power and thermal management are critical.

IC Role / Device Role / Timing Role: Main SoC core regulator with enable-controlled sequencing and Power Good signaling for system-level power management.

Use Value: 5µA shutdown current and –40°C to +125°C operation allow reliable low-power standby and extended-temperature deployment in unventilated enclosures.

Use Scenario: Supplying 3.3V and 5.0V rails to microcontrollers, ADCs, and interface ICs in programmable logic controllers (PLCs) and motor drives operating in harsh factory environments.

IC Role / Device Role / Timing Role: Robust, self-protected buck stage replacing discrete FET+controller designs to improve MTBF and reduce BOM count.

Use Value: Integrated foldback current limit and thermal shutdown eliminate need for external fault monitoring circuits, simplifying safety-certified designs.

Equivalent & Alternatives

The following parts are listed as comparable options for similar synchronous buck regulator applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
MP2451DT-LF-Z	3A max output, 2MHz switching, no integrated high-side FET - requires external MOSFETs.	Suitable only for lower-current applications (<3A); lacks pre-biased startup and hiccup-mode protection.	Select when board space allows discrete FET layout and load current is ≤3A; not drop-in for MIC26903-ZAYJL-TR's 9A capability.
TPS549D22RSAR	9A output, 2MHz, D-CAP3 control, but 4.5V–18V input range - cannot support 24V input.	Valid for 12V systems only; lacks 28V rating and Hyper Speed Control™ transient performance.	Choose for higher-frequency, smaller-inductor designs in ≤18V systems; verify thermal derating at full load in 125°C ambient.

Compared with MP2451DT-LF-Z and TPS549D22RSAR, the MIC26903-ZAYJL-TR uniquely combines 28V input tolerance, 9A integrated power stage, and adaptive on-time control optimized for high-delta-V conversion-making it the only option among the three qualified for 24V→1.0V telecom POL use cases.

Availability

MIC26903-ZAYJL-TR is available at Aetrix Electronics and suitable for distributed point-of-load regulation, graphics card core power, and industrial embedded controller applications requiring stable component supply, long-term lifecycle support, and guaranteed Pb-free compliance.

Supply support for MIC26903-ZAYJL-TR 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

Micrel Inc. was a U.S.-based analog and power IC manufacturer headquartered in San Jose, CA, acquired by Microchip Technology in 2015. Known for high-performance SuperSwitcher™ and Hyper Speed Control™ DC-DC solutions.

The MIC26903-ZAYJL-TR belongs to Micrel's SuperSwitcher™ II family, engineered specifically for high-efficiency, high-transient-response POL conversion in telecom, networking, and computing infrastructure where wide input range and minimal external components are critical.

FAQ

What is the maximum input voltage supported by the MIC26903-ZAYJL-TR?

The MIC26903-ZAYJL-TR supports an absolute maximum input voltage of 29V on PVIN, with recommended operating range from 4.5V to 28V. This 28V upper limit enables direct compatibility with 24V industrial and telecom distribution rails while maintaining margin for transients. Exceeding 28V risks violating the device's Absolute Maximum Ratings and may trigger overvoltage protection or permanent damage.

Does the MIC26903-ZAYJL-TR require external compensation components?

No, the MIC26903-ZAYJL-TR does not require external compensation components. Its Hyper Speed Control™ architecture uses adaptive on-time control with internal ripple-based feedback, eliminating the need for external RC networks or type-II/type-III compensators. Stability is maintained across all output capacitor types-including low-ESR ceramics-via the Any Capacitor® design, verified per the manufacturer's application notes.

How does the MIC26903-ZAYJL-TR handle short-circuit conditions?

The MIC26903-ZAYJL-TR implements foldback current limiting and "hiccup mode" short-circuit protection. When output current exceeds 12.5–20A (depending on temperature), it disables switching, enters a low-power state for ~20ms, then attempts restart. This cycle repeats until fault clears-limiting power dissipation and preventing thermal runaway. The CS pin monitors low-side R_DS(ON) continuously, requiring no external sense resistor.

Can the MIC26903-ZAYJL-TR start up safely when the output voltage is already present?

Yes, the MIC26903-ZAYJL-TR supports safe startup into a pre-biased output. Its control architecture prevents reverse current flow during enable assertion by disabling the high-side MOSFET until the feedback voltage rises above the soft-start threshold. This feature is essential for hot-swap applications and redundant power systems where downstream rails may remain energized during reconfiguration.

What thermal performance can be expected from the MIC26903-ZAYJL-TR at full 9A load?

At 9A output with 12V input and 1.8V output on a standard 5-in² 4-layer PCB with 2oz copper, the MIC26903-ZAYJL-TR junction temperature reaches ~100°C at 25°C ambient. Thermal derating curves show usable current drops to ~7A at 75°C ambient and ~4A at 100°C ambient. The 28-pin QFN package's θ_JA of 28°C/W assumes proper thermal pad soldering and airflow; adding heatsinking or forced air extends full-load capability.

MIC26903-ZAYJL-TR Specifications

Product attributes: Attribute value

Manufacturer:: Microchip Technology

Series:: Hyper Speed Control®, SuperSwitcher II™

Package/Case:: 28-PowerVQFN

Packaging:: Tape & Reel (TR)

Product Status:: Active

Function:: Step-Down

Output Configuration:: Positive

Topology:: Buck

Output Type:: Adjustable

Number of Outputs:: 1

Voltage - Input (Min):: 4.5V

Voltage - Input (Max):: 28V

Voltage - Output (Min/Fixed):: 0.6V

Voltage - Output (Max):: 5.5V

Current - Output:: 9A

Frequency - Switching:: 600kHz

Synchronous Rectifier:: Yes

Operating Temperature:: -40°C ~ 125°C (TJ)

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: 28-QFN (5x6)

MIC26903-ZAYJL-TR FAQ

1.How can I place an order for MIC26903-ZAYJL-TR through Aetrix?

Please submit a Request for Quotation (RFQ) for MIC26903-ZAYJL-TR 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 MIC26903-ZAYJL-TR reliable?

The price and inventory of MIC26903-ZAYJL-TR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MIC26903-ZAYJL-TR is usually 5 days.

3.What payment methods are accepted for MIC26903-ZAYJL-TR?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MIC26903-ZAYJL-TR transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for MIC26903-ZAYJL-TR?

MIC26903-ZAYJL-TR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your MIC26903-ZAYJL-TR 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 MIC26903-ZAYJL-TR?

For technical support, including MIC26903-ZAYJL-TR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MIC26903-ZAYJL-TR requirements.

6.How does Aetrix verify that MIC26903-ZAYJL-TR is sourced from the original manufacturer or authorized distributors?

All MIC26903-ZAYJL-TR 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 MIC26903-ZAYJL-TR meets industry standards.

7.What is the process for return or replacement of MIC26903-ZAYJL-TR?

All MIC26903-ZAYJL-TR units undergo pre-shipment inspection (PSI). If there is an issue with MIC26903-ZAYJL-TR, 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 MIC26903-ZAYJL-TR part is unused and in its original packaging.

Return procedure for MIC26903-ZAYJL-TR:

1.Submit a request within 90 days.

2.Obtain a Return Material Authorization (RMA) from Aetrix.

Tech Hub

2026-09-07 TTL vs CMOS Logic Levels: 74HC and 74HCT Compatibility Explained

TTL and CMOS logic families differ in thresholds, loading, output drive, power and timing. This engineering guide compares 74HC and 74HCT, calculates noise margins and checks 3.3 V/5 V compatibility.

2026-09-04 Logic Level Shifter: How to Connect 3.3V and 5V Logic Safely

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.

2026-09-03 74HC595 vs TPIC6B595: Output Drive, Pinout, Current, and Load Selection

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…

2026-09-02 74HC595 Pinout, Timing, Output Current, and Applications

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…

2026-09-01 Latch vs Flip-Flop: Timing, Differences and Design Choices

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…

2026-08-30 D Latch Circuit: Truth Table, Timing, ICs and Applications

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 …

2026-08-28 SR Latch Explained: NOR and NAND Circuits, Truth Tables, and Applications

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…

2026-08-27 Latch Circuit: SR and D Latches, Truth Tables, Timing, and Applications

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…

2026-08-21 What Is an LED Driver? Types, Circuits, Dimming, and Selection

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…

2026-08-18 Operational Amplifier (Op Amp): Basics, Configurations, Feedback and Applications

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…