onsemi MC33567D-1R2G

Overview

MC33567D-1R2G from onsemi is a dual linear power supply controller IC designed to drive two external N-channel MOSFETs for independent regulation of high-current motherboard supply planes. It delivers 1.818 V (Output 1) and 1.515 V (Output 2), supports undervoltage short-circuit hiccup-mode protection, features TTL-compatible shutdown inputs, and operates with 12 V VCC supply. It is used in AGP/GTL+ and I/O/memory termination power delivery on PC motherboards.

For engineers reviewing the MC33567D-1R2G datasheet, pinout, applications, or equivalent options, key selection considerations include dual-output voltage accuracy (±2.5% regulation), gate drive capability (20 mA typical source, 7 mA sink), SO-8 package thermal resistance (159°C/W), hiccup-mode fault response timing (325 µs detection, 0.97 ms ON time), and bypass-mode support on Output 2 for 3.3 V AGP card detection.

Technical Context

The MC33567D-1R2G implements two independent linear regulator control loops, each using external N-channel MOSFETs as pass elements. Each loop includes dedicated SENSE pins for remote load voltage feedback, internal error amplifiers, and PWM-like hiccup-mode protection triggered when output drops below 75% of nominal for >250 µs.

Its shutdown architecture uses TTL-level SHDN1/SHDN2 inputs (1.13 V typical threshold, 130 mV hysteresis) to enable/disable each regulator independently. Output 2 supports Vin-bypass mode (activated at SHDN2 >4.1 V), where the FET is fully enhanced to pass input voltage minus V_DS(on), enabling AGP card type detection.

Key Specifications

Pinout & Package

MC33567D-1R2G is housed in an SO-8 (D suffix, Case 751-07) surface-mount package with 1.27 mm pitch, 4.9 mm × 3.9 mm body, and exposed pad not present. Thermal resistance is 159°C/W junction-to-ambient on minimum pad board.

Key Features

Applications

Equivalent & Alternatives

The following parts are listed as comparable options for similar dual linear controller applications.

Compared with MC33567D-1R2 (Pb version), MC33567D-1R2G offers identical performance with RoHS compliance; compared with NCP5363DR2G, it trades higher efficiency for lower noise, simpler layout, and integrated AGP detection - making it optimal for legacy motherboard I/O and AGP power where linear regulation suffices.

Availability

MC33567D-1R2G is available at Aetrix Electronics and suitable for motherboard power delivery, AGP card detection systems, and dual-rail memory termination applications requiring stable component supply, long-term lifecycle support, and RoHS-compliant packaging.

Supply support for MC33567D-1R2G 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 focused on energy-efficient innovation for automotive, industrial, cloud, and IoT applications, with leadership in power management, analog, and sensor technologies.

The MC33567 series belongs to onsemi's legacy power management portfolio, specifically engineered for high-current linear regulation in PC motherboard applications - emphasizing precision voltage control, fault resilience, and hardware-based peripheral detection like AGP card classification.

FAQ

What is the primary function of the MC33567D-1R2G in motherboard designs?

The MC33567D-1R2G serves as a dual linear controller that regulates two independent supply rails - 1.818 V for I/O planes and 1.515 V for AGP/GTL+ interfaces - using external N-channel MOSFETs. It provides remote sensing, hiccup-mode short-circuit protection, and SHDN-controlled bypass functionality essential for reliable motherboard power delivery and AGP card detection. Its design ensures stable operation across 0–80°C ambient and load currents up to 1.3 A per rail.

Does the MC33567D-1R2G support RoHS-compliant manufacturing?

Yes, the "G" suffix in MC33567D-1R2G explicitly denotes a Pb-free lead finish compliant with RoHS Directive 2011/65/EU. The device uses matte tin plating over copper leadframe and meets IPC/JEDEC J-STD-020 moisture sensitivity level 3. This makes MC33567D-1R2G suitable for lead-free reflow assembly processes and environmentally regulated production environments.

How does the hiccup-mode protection work in the MC33567D-1R2G?

When either output drops below 75% of its nominal voltage for longer than 250 µs - indicating overload or short-circuit - the MC33567D-1R2G enters hiccup mode: it disables the affected gate driver for 47.7 ms (typical OFF time), then re-enables it for 0.97 ms (typical ON time). This cycle repeats until the fault clears. This behavior limits average power dissipation and allows automatic recovery without system reset, preserving reliability in high-current motherboard rails.

Can the MC33567D-1R2G regulate voltages other than 1.818 V and 1.515 V?

No - the MC33567D-1R2G is factory-trimmed for fixed outputs of 1.818 V (Output 1) and 1.515 V (Output 2), as confirmed in the ordering table and DC characteristics section. While the datasheet mentions adjustable scaling via external resistive networks, this method is not validated for MC33567D-1R2G and risks compromising regulation accuracy, stability, and short-circuit response. For variable outputs, onsemi recommends alternative controllers like the NCP102x family.

What external components are required for stable operation of the MC33567D-1R2G?

Each output channel requires one external N-channel MOSFET (e.g., MTD3055VL), four 100 µF electrolytic output capacitors (C1–C4), and dedicated SENSE traces routed directly to the load. Input decoupling (12 V rail) and proper PCB layout - including short DRV/SENSE traces, separation from noisy return paths, and adequate copper pour for thermal dissipation - are mandatory. The datasheet specifies 100 µF/30 mΩ ESR capacitors for stability with the MTD3055VL.