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

Monolithic Power Systems Inc. MP8859GQ-0000-P

Name: MP8859GQ-0000-P
Brand: Monolithic Power Systems Inc.
SKU: MP8859GQ-0000-P
Price: 2.40 USD
Availability: InStock
Rating: 5 (2 reviews)

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Part No.:: MP8859GQ-0000-P

Manufacturer:: Monolithic Power Systems Inc.

Category:: Voltage Regulators - DC DC Switching Regulators

Package:: 16-PowerVFQFN

Datasheet:: MP8859GQ-0000-P.pdf

Description:: IC REG BUCK BOOST ADJ 3A 16QFN

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Product details

Overview

MP8859GQ-0000-P from Monolithic Power Systems is a synchronous 4-switch integrated buck-boost DC/DC converter with I²C interface, operating from 2.8V to 22V input and delivering up to 3A output current at programmable 1V–20.47V output voltage. It implements constant-on-time (COT) control in buck mode and constant-off-time in boost mode, supports USB PD sourcing ports, and integrates four low-R_DS(ON) MOSFETs (25mΩ HS / 21mΩ LS) in a QFN-16 (3mm×3mm) package.

For engineers reviewing the MP8859GQ-0000-P datasheet, MP8859GQ-0000-P pinout, MP8859GQ-0000-P application, or MP8859GQ-0000-P equivalent, key selection considerations include I²C-programmable output voltage (10mV resolution), adjustable CC current limit via OC pin, hiccup-mode OVP/SCP protection, thermal warning/shutdown, and OTP-configurable soft-start (900μs default) and line-drop compensation (150mV @3A).

Technical Context

The MP8859 operates across three distinct regulation modes-buck (VIN > VOUT), boost (VIN < VOUT), and buck-boost (VIN ≈ VOUT)-using a single inductor and four internal power switches. Its dual-mode COT/COT-based control architecture ensures fast load transient response (<400μs recovery for 0–3A step) and seamless mode transitions without output voltage glitching.

Internal circuitry includes a 3.6V VCC LDO regulator, dual bootstrap drivers (BST1/BST2) for high-side gate drive, analog ground (AGND) separation for feedback stability, and an ALT pin that asserts low on OVP, SCP, OCP, or thermal warning events. The I²C interface supports 400kHz–3.4MHz clock rates and four configurable slave addresses via the ADD pin resistor divider.

Key Specifications

Parameter	Value and Actual Design Meaning
Input Voltage Range	2.8V to 22V - supports wide-input industrial, automotive, and USB PD bus supplies without external pre-regulation.
Output Voltage Range	1V to 20.47V (10mV I²C resolution) - enables precise USB PD profile selection and dynamic voltage scaling in portable systems.
Max Output Current	3A continuous (5V–12V), 2A at 20V - limited by thermal design and output capacitor ESR; supports 4A peak input current during boost operation.
Switching Frequency	500kHz ±20% - fixed-frequency operation simplifies EMI filtering; frequency drops below 3V VOUT per datasheet note.
HS/LS R_DS(ON)	25mΩ (HS), 21mΩ (LS) - enables >90% efficiency at 12V→5V/3A (forced PWM) and reduces conduction loss in high-current buck-boost paths.
OVP/SCP Response	Hiccup-mode protection - latches off for 10ms after fault detection, then auto-retries; prevents thermal runaway during sustained short-circuit conditions.
I²C Address Options	Four unique addresses via ADD pin resistor divider (60H–66H) - allows multiple MP8859 devices on same bus without address conflict.

Pinout & Package

MP8859GQ-0000-P is housed in a thermally enhanced 16-pin QFN package (3mm × 3mm, 0.5mm pitch) with exposed thermal pad (EP) connected to GND. The package supports ≤4.8W power dissipation at +25°C ambient (θ_JA = 26°C/W on 4-layer EV8859-Q-00B PCB) and is UL-certified (E322138, E500002-A1-CB-1).

Pin/Terminal	Circuit Role	Design Meaning
1 IN	Main power input	Drain node of internal high-side switch A; requires local 100µF low-ESR input capacitor placed adjacent to pin.
2,11 GND	Power ground	Primary return path for high-current switching loops; must be solid copper plane with multiple vias to inner-layer ground.
3 EN	Enable control	Active-high logic input (1.10V threshold); internal 2MΩ pull-down enables default-off behavior when unconnected.
4 ADD	I²C address select	Analog input setting one of four I²C slave addresses (60H–66H) via external resistor divider to VCC.
5 SCL	I²C clock	Open-drain input supporting up to 3.4MHz; requires external pull-up to 1.8V–5V logic rail.
6 SDA	I²C data	Open-drain bidirectional I²C data line; shares same pull-up as SCL.
7 OC	Current limit set	Analog input configuring output CC limit (3.5A default with 21.5kΩ resistor); enables precise overcurrent threshold tuning.
8 ALT	Alert output	Open-drain fault indicator (low on OVP/SCP/OCP/thermal warning); requires external pull-up for system-level monitoring.
9 VCC	Internal LDO output	3.6V regulated supply for internal logic; decoupled with 1µF ceramic capacitor directly at pin.
10 AGND	Analog reference ground	Separate ground for feedback and sensing circuits; must be tied to GND at single point near IC.
12 OUT	Regulated output	High-current output node; requires low-ESR bulk capacitor (100µF) and ceramic (22µF) placed within 3mm of pin.
13 BST2	Bootstrap supply for SW2	Connects 100nF capacitor between BST2 and SW2 to generate floating gate drive voltage for high-side switch D.
14 SW2	Switch node 2	Connection point for inductor second terminal and low-side switch C/high-side switch D; forms half-bridge leg.
15 SW1	Switch node 1	Connection point for inductor first terminal and low-side switch B/high-side switch A; forms complementary half-bridge leg.
16 BST1	Bootstrap supply for SW1	Connects 100nF capacitor between BST1 and SW1 to generate floating gate drive voltage for high-side switch A.

Key Features

Feature	Design Value
I²C-programmable output voltage	1V–20.47V in 10mV steps - eliminates external resistor dividers and enables runtime voltage adjustment for adaptive power rails.
OTP non-volatile configuration	Stores default settings (5V VOUT, 3.5A I_LIM, 500kHz f_SW, forced PWM, 900μs soft-start) - ensures consistent startup behavior without host MCU initialization.
Programmable line-drop compensation	150mV compensation at 3A - actively adjusts VOUT setpoint to counteract IR drop in long PCB traces or cables, maintaining load regulation.
EN shutdown discharge	Internal discharge path for VOUT when EN = low - prevents lingering output voltage after disable, critical for safe hot-plug operation.
Thermal warning + shutdown	150°C trip with 20°C hysteresis - provides early overtemperature alert (ALT pin) before shutdown, enabling system-level thermal management.

Applications

USB PD Sourcing Port

Buck-Boost Bus Supply

Use Scenario: Portable power bank or laptop dock providing USB-C PD power delivery with variable output (5V/9V/15V/20V).

IC Role / Device Role / Timing Role: Primary buck-boost controller regulating VBUS from battery or adapter input while communicating PD contract negotiation via I²C.

Use Value: Eliminates need for discrete buck + boost stages; 3A capability supports 60W PD profiles; hiccup-mode SCP protects against cable faults.

Use Scenario: Industrial IoT gateway requiring stable 12V rail from wide-range 5–24V field bus input.

IC Role / Device Role / Timing Role: Central power management IC converting fluctuating bus voltage to regulated system rail with minimal external components.

Use Value: Maintains regulation across full input range without mode-switching glitches; thermal warning enables predictive maintenance before shutdown.

Automotive Infotainment Display

Medical Portable Monitor

Use Scenario: LCD backlight driver in vehicle head unit powered from 9–16V battery with cold-crank tolerance down to 6V.

IC Role / Device Role / Timing Role: High-efficiency buck-boost converter supplying constant-current LED string driver with programmable dimming interface.

Use Value: Operates through 6V cold-crank events; I²C allows brightness and fault status reporting to main MCU; UL certification meets automotive safety requirements.

Use Scenario: Battery-powered patient monitor needing 5V/3.3V rails from 7.4V Li-ion pack across full discharge curve (8.4V–6.0V).

IC Role / Device Role / Timing Role: Primary DC/DC regulator delivering clean, stable power to ADC, display, and wireless modules with low quiescent current.

Use Value: 3μA shutdown current extends battery life; PFM/PWM auto-mode optimizes light-load efficiency; medical-grade reliability via UL60950-1 certification.

Equivalent & Alternatives

The following parts are listed as comparable options for similar buck-boost converter applications.

Alternative Part	Technical Difference	Application Difference	Selection Advice
TI TPS63802	2.5–5.5V input, 1.8–5.5V output, 2A max, I²C interface, no OTP, lower R_DS(ON) (16mΩ/12mΩ)	Targeted at low-voltage portable devices only; lacks 22V input capability and USB PD voltage range support.	Select when input is strictly sub-5.5V and space-constrained; avoid for automotive or wide-input industrial use.
Analog Devices LT8390A	6–40V input, 2.5–30V output, 3.5A, no I²C, analog FB/ILIM pins, spread-spectrum EMI reduction	Requires external resistors for VOUT/I_LIM; no digital configuration or fault reporting; superior EMI performance for noise-sensitive systems.	Choose for high-EMI environments (e.g., MRI equipment) where I²C control is unnecessary and input exceeds 22V.

Compared with TPS63802 and LT8390A, MP8859GQ-0000-P uniquely balances wide 2.8–22V input, USB PD-compliant 1–20.47V output, I²C configurability, and OTP persistence-making it optimal for embedded systems requiring flexible, field-updatable power rails without sacrificing robustness or certification.

Availability

MP8859GQ-0000-P is available at Aetrix Electronics and suitable for USB PD sourcing ports, industrial bus supplies, automotive infotainment displays, and medical portable monitors requiring stable component supply with full lifecycle support.

Supply support for MP8859GQ-0000-P 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

Monolithic Power Systems (MPS) is a fabless semiconductor company specializing in high-performance analog and power ICs, with over two decades of expertise in DC/DC conversion, motor drivers, and LED lighting controllers.

The MP8859 belongs to MPS's USB PD and wide-input buck-boost product line, designed specifically for compact, digitally controllable power delivery in portable, automotive, and industrial systems demanding high integration and regulatory compliance.

FAQ

What is the default output voltage and how is it configured?

The MP8859GQ-0000-P ships with factory-programmed OTP defaults: 5V output voltage, 3.5A current limit (with 21.5kΩ OC resistor), 500kHz switching frequency, and forced PWM mode. These values are stored in one-time programmable memory and persist across power cycles without host I²C initialization.

Does MP8859GQ-0000-P support true USB PD communication or only voltage negotiation?

MP8859GQ-0000-P does not implement the full USB PD protocol stack (e.g., BMC signaling, policy engine). It supports USB PD *voltage profile sourcing* via I²C-programmable VOUT (1V–20.47V) and CC current limiting, but requires an external PD controller (e.g., Cypress CCGx, STUSB4500) to handle USB-C CC logic and contract negotiation.

How is thermal performance validated and what layout guidance applies?

Thermal performance is characterized on the EV8859-Q-00B 4-layer evaluation board (64mm×64mm), achieving θ_JA = 26°C/W. Critical layout practices include: (1) connecting the exposed thermal pad to a solid GND plane with ≥9 thermal vias, (2) placing input/output capacitors within 3mm of respective pins, and (3) routing SW1/SW2 nodes with minimum loop area to reduce EMI.

Can the ALT pin be used for system-level fault recovery?

Yes. The open-drain ALT pin asserts low on OVP, SCP, OCP, or thermal warning events. By monitoring ALT with a microcontroller GPIO, systems can initiate controlled shutdown, log fault conditions, or trigger retry sequences. Hiccup-mode recovery (10ms off-time) allows automatic resumption if fault clears, enabling autonomous recovery in unattended deployments.

What is the minimum output voltage and under what conditions does switching frequency change?

The absolute minimum output voltage is 1V, supported across the full temperature and input range. Per datasheet Note 1, switching frequency decreases below 3V VOUT to maintain regulation stability; this is an inherent characteristic of the COT control architecture and does not indicate malfunction.

Is the OC pin compatible with standard current-sense resistors or only MOSFET-based sensing?

The OC pin is designed for direct connection to an external current-sense resistor (e.g., 21.5kΩ for 3.5A default) and does not require or support external shunt resistors. The IC uses internal MOSFET sensing for CC limit detection, eliminating the need for precision external sense resistors and associated power loss.

How does the MP8859 handle input UVLO during cold-crank scenarios?

UVLO rising threshold is 2.65V (±150mV), with 160mV hysteresis. During automotive cold-crank (e.g., 6V battery sag), the device remains operational down to ~2.5V input and re-enables cleanly once VIN rises above 2.65V - ensuring uninterrupted power to critical loads during transient brownouts.

MP8859GQ-0000-P Specifications

Product attributes: Attribute value

Manufacturer:: Monolithic Power Systems Inc.

Series:: -

Package/Case:: 16-PowerVFQFN

Packaging:: Tape & Reel (TR)

Product Status:: Active

Function:: Step-Up/Step-Down

Output Configuration:: Positive

Topology:: Buck-Boost

Output Type:: Adjustable

Number of Outputs:: 1

Voltage - Input (Min):: 2.8V

Voltage - Input (Max):: 22V

Voltage - Output (Min/Fixed):: 1V

Voltage - Output (Max):: 20.47V

Current - Output:: 3A

Frequency - Switching:: 500kHz

Synchronous Rectifier:: Yes

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

Grade:: -

Qualification:: -

Mounting Type:: Surface Mount

Supplier Device Package:: 16-QFN (3x3)

MP8859GQ-0000-P FAQ

1.How can I place an order for MP8859GQ-0000-P through Aetrix?

Please submit a Request for Quotation (RFQ) for MP8859GQ-0000-P 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 MP8859GQ-0000-P reliable?

The price and inventory of MP8859GQ-0000-P are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for MP8859GQ-0000-P is usually 5 days.

3.What payment methods are accepted for MP8859GQ-0000-P?

We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for MP8859GQ-0000-P transactions.

Note: Certain payment methods may incur a processing fee.

4.How is shipping managed for MP8859GQ-0000-P?

MP8859GQ-0000-P orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.

Once your MP8859GQ-0000-P 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 MP8859GQ-0000-P?

For technical support, including MP8859GQ-0000-P datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your MP8859GQ-0000-P requirements.

6.How does Aetrix verify that MP8859GQ-0000-P is sourced from the original manufacturer or authorized distributors?

All MP8859GQ-0000-P 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 MP8859GQ-0000-P meets industry standards.

7.What is the process for return or replacement of MP8859GQ-0000-P?

All MP8859GQ-0000-P units undergo pre-shipment inspection (PSI). If there is an issue with MP8859GQ-0000-P, 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 MP8859GQ-0000-P part is unused and in its original packaging.

Return procedure for MP8859GQ-0000-P:

1.Submit a request within 90 days.

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

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