Overview
The NCP1589L, produced by onsemi, is a low-cost PWM (Pulse Width Modulation) controller designed for synchronous buck converter applications. It operates from a 5 V or 12 V supply and can produce output voltages as low as 0.8 V, making it versatile for various power supply needs. The device is optimized for high efficiency, especially in light load conditions, and features advanced transient response and protection mechanisms.
Key Specifications
| Parameter | Min | Max | Unit | |
|---|---|---|---|---|
| VCC Input Voltage Range | 4.5 | 13.2 | V | |
| BOOT Voltage Range | 4.5 | 30 | V | |
| Output Voltage Range | 0.8 | 5 | V | |
| Operating Frequency Range | 200 | 500 | kHz | |
| Gate Driver Current | 1.5 | A | ||
| Maximum Duty Cycle | 80 | % | ||
| Operating Junction Temperature Range | 0 | 150 | °C | |
| Operating Ambient Temperature Range | 0 | 95 | °C |
Key Features
- Ramp Pulse Modulation Control: Provides superior load step and release response.
- Precision 0.8 V Internal Reference: Allows for adjustable output voltage.
- Internal 1.5 A Gate Drivers: Supports high-side and low-side MOSFETs.
- Light Load Efficiency: Features adaptive non-overlap circuitry and diode emulation.
- Programmable Overcurrent Protection: Adjustable via an external resistor.
- Output Overvoltage and Undervoltage Protection: Ensures safe operation by latching faults and disabling the device if necessary.
- Input Undervoltage Lockout (UVLO): Prevents operation below a safe input voltage threshold.
- Internal Soft-Start: Reduces inrush current during startup.
- Power Good Signal: Indicates the status of the converter output voltage.
Applications
- Graphics Cards
- Desktop Computers
- Servers and Networking Equipment
- DSP & FPGA Power Supply
- DC-DC Regulator Modules
Q & A
- What is the input voltage range for the NCP1589L?
The input voltage range for the NCP1589L is from 4.5 V to 13.2 V.
- What is the minimum output voltage that the NCP1589L can produce?
The minimum output voltage that the NCP1589L can produce is 0.8 V.
- How does the NCP1589L handle overcurrent protection?
The NCP1589L monitors the voltage across the low-side MOSFET and triggers an overcurrent protection fault if the voltage exceeds a set threshold. This threshold can be adjusted using an external resistor.
- What protection mechanisms does the NCP1589L include?
The NCP1589L includes programmable overcurrent protection, output overvoltage and undervoltage protection, and input undervoltage lockout (UVLO).
- How does the NCP1589L manage light load conditions?
In light load conditions, the NCP1589L operates in discontinuous current mode with a scaled-down frequency to reduce power consumption. It also features adaptive zero current detection to minimize diode conduction period.
- What is the purpose of the Power Good (PGOOD) signal?
The Power Good (PGOOD) signal indicates the status of the converter output voltage, going low during soft-start, overvoltage, or undervoltage faults.
- How is the output voltage adjusted in the NCP1589L?
The output voltage is adjusted using an external resistor divider network connected to the feedback pin, maintaining 0.8 V at the FB pin.
- What is the operating frequency range of the NCP1589L?
The operating frequency range of the NCP1589L is from 200 kHz to 500 kHz in continuous current conduction mode.
- Does the NCP1589L have internal soft-start capabilities?
Yes, the NCP1589L includes an internal soft-start mechanism to prevent excess inrush current during startup.
- What is the maximum duty cycle of the NCP1589L?
The maximum duty cycle of the NCP1589L is 80%.
