MP4423GQ-Z Model Information

Basic Information

• Manufacturer: Monolithic Power Systems (MPS)
• Model Number: MP4423GQ-Z
• Revision: 1.0
• Date: August 18, 2014
• Website: www.MonolithicPower.com
• Proprietary Information: Patent Protected. Unauthorized Photocopy and Duplication Prohibited.

Product Overview

The MP4423 is a high-frequency, synchronous, rectified, step-down, switch-mode converter with built-in power MOSFETs. It offers a compact solution for achieving a 3A continuous output current with excellent load and line regulation over a wide input supply range. The MP4423 operates in synchronous mode for higher efficiency and provides a fast transient response due to its current-mode operation.

Features

• Wide Input Range: 4V to 30V continuous operating input range
• High Input Transient Tolerance: 36V for automotive load dump
• Low RDS(ON) MOSFETs: 85mΩ/55mΩ
• High Efficiency: Synchronous mode operation
• Default Switching Frequency: 410kHz
• External Clock Synchronization: 200kHz to 2.2MHz
• High Duty Cycle: Suitable for automotive cold-crank
• Power-Save Mode: Enhances efficiency at light loads
• Internal Soft-Start: Prevents inrush current
• Protection Features: Over-current protection, hiccup mode, thermal shutdown
• Output Voltage Range: Adjustable from 0.8V
• Package: QFN-8 (3mm x 3mm)

Applications

• Automotive
• Industrial Control Systems
• Distributed Power Systems

Ordering Information

• Part Number: MP4423GQ-Z (Tape & Reel)
• Package: QFN-8 (3mm x 3mm)
• Top Marking: AJV (Product Code), Y (Year Code), LLL (Lot Number)

Absolute Maximum Ratings

• Input Voltage (VIN): -0.3V to 40V
• Switch Voltage (VSW): -0.3V to 41V
• Bootstrap Voltage (VBS): VSW + 6V
• All Other Pins: -0.3V to 6V
• Continuous Power Dissipation (QFN-8): 2.27W at TA = +25°C
• Junction Temperature: 150°C
• Lead Temperature: 260°C
• Storage Temperature: -65°C to 150°C
• Thermal Resistance (θJA): 55°C/W (QFN-8)

Electrical Characteristics (VIN = 12V, TJ = +25°C)

• Supply Current (Shutdown): 8 μA
• Supply Current (Quiescent): 0.5 mA to 0.7 mA
• HS Switch-ON Resistance (RON_HS): 85 mΩ to 105 mΩ
• LS Switch-ON Resistance (RON_LS): 55 mΩ to 75 mΩ
• Switch Leakage (ILKG_SW): 1 μA
• Current Limit (ILIMIT): 3.2 A to 5.5 A
• Oscillator Frequency (fSW): 320 kHz to 500 kHz
• Fold-Back Frequency (fFB): 70 kHz to 130 kHz
• Maximum Duty Cycle (DMAX): 92% to 95%
• Minimum ON Time (tON_MIN): 70 ns
• Sync Frequency Range (fSYNC): 200 kHz to 2.4 MHz
• Feedback Voltage (VFB): 780 mV to 804 mV
• Feedback Current (IFB): 10 nA to 100 nA
• EN Rising Threshold (VEN_RISING): 1.15 V to 1.65 V
• EN Falling Threshold (VEN_FALLING): 1.05 V to 1.45 V
• EN Threshold Hysteresis (VEN_HYS): 150 mV
• EN Input Current (IEN): 4 μA to 6 μA
• VIN Under-Voltage Lockout Threshold-Rising (INUVRISING): 3.3 V to 3.7 V
• VIN Under-Voltage Lockout Threshold-Falling (INUVFALLING): 3.1 V to 3.5 V
• VIN Under-Voltage Lockout Threshold-Hysteresis (INUVHYS): 200 mV
• VCC Regulator (VCC): 4.6 V to 5.2 V
• VCC Load Regulation: 1.5% to 4%
• Soft-Start Period (tSS): 0.45 ms to 2.55 ms
• Thermal Shutdown: 150°C to 170°C
• Thermal Hysteresis: 30°C
• PG Rising Threshold (PGVth_RISING): 86% to 94% of VFB
• PG Falling Threshold (PGVth_FALLING): 80% to 88% of VFB
• PG Threshold Hysteresis (PGVth_HYS): 6% of VFB
• PG Rising Delay (PGTd_RISING): 40 μs to 160 μs
• PG Falling Delay (PGTd_FALLING): 30 μs to 95 μs
• PG Sink Current Capability: 0.1 V to 0.3 V
• PG Leakage Current (ILKG_PG): 10 nA to 100 nA

Pin Functions

• FB: Feedback pin for setting output voltage
• VCC: Bias supply pin, decouple with 0.1 μF to 0.22 μF capacitor
• EN/SYNC: Enable/Synchronize pin for enabling the regulator or synchronizing to an external clock
• BST: Bootstrap pin for the high-side switch driver
• GND: System ground, connect with copper traces and vias
• SW: Switch output, connect with a wide PCB trace
• IN: Supply voltage input, connect with a wide PCB trace
• PG: Power Good output, open drain

Typical Performance Characteristics

• The datasheet includes detailed performance graphs for various operating conditions, such as efficiency, output voltage ripple, and transient response.

Application Information

• Setting the Output Voltage: Use an external resistor divider to set the output voltage.
• Selecting the Inductor: Choose an inductor with a DC current rating at least 25% higher than the maximum load current.
• Input Capacitor: Use low ESR capacitors, such as ceramic capacitors with X5R or X7R dielectrics.
• Output Capacitor: Use low ESR capacitors to maintain the DC output voltage and minimize ripple.
• BST Resistor and External BST Diode: A 20Ω resistor in series with the BST capacitor is recommended to reduce SW spike voltage.

PCB Layout Recommendations

• Place the input capacitor close to the IN and GND pins.
• Use a large ground plane and add vias near the GND pin.
• Route SW and BST away from sensitive analog areas.
• Place the T-type feedback resistor close to the chip.

Package Information

• Package Type: QFN-8 (3mm x 3mm)
• Pin Configuration: See datasheet for detailed pinout diagram.