XZ2105
High-efficiency 3A synchronous buck converter with 2.5MHz switching frequency for compact designs
Product Overview
Description
The XZ2105 is a high-efficiency synchronous buck converter capable of delivering up to 3A continuous output current. With a switching frequency of 2.5MHz, it enables the use of small external inductors and capacitors, reducing overall solution size.
The device operates from a 2.5V to 5.5V input voltage range, making it ideal for single Li-ion battery-powered applications. It features internal compensation, fast transient response, and excellent load regulation. The peak current mode control architecture provides fast transient response with minimal output voltage ripple.
Comprehensive protection features include cycle-by-cycle current limit, thermal shutdown, and undervoltage lockout. The XZ2105 is available in a compact 2mm x 2mm QFN package, making it perfect for space-constrained applications such as smartphones, tablets, and portable devices.
Product Series
XZ
Primary Application
Smartphones and tablets
Key Features
- High efficiency up to 95%
- 2.5MHz switching frequency for small external components
- 3A continuous output current capability
- Internal compensation for easy design
- Fast transient response
- Cycle-by-cycle current limit
- Thermal shutdown protection
- Power-good indicator output
Specifications
| Input Voltage | 2.5V - 5.5V |
|---|---|
| Output Voltage | 0.6V - Vin |
| Output Current | 3A |
| Switching Frequency | 2.5MHz |
| Efficiency | Up to 95% |
| Operating Temperature | -40°C to +85°C |
| Package | QFN-8 (2mm x 2mm) |
Applications
Smartphones and tablets
Electronic system design
Portable media players
Electronic system design
Digital cameras
Electronic system design
IoT devices
Electronic system design
Industrial control systems
Industrial automation and control
FAE Expert Insights
"The XZ2105 is an excellent buck converter that I've used in several smartphone power designs. The 2.5MHz switching frequency really makes a difference - you can use a 1μH inductor in a small 2mm x 1.6mm package, saving significant board space. Efficiency is impressive, consistently achieving 93-95% in typical operating conditions. The internal compensation simplifies design - no need to calculate external compensation networks. Transient response is fast enough for most processor loads, though for the most demanding applications you might want to add extra output capacitance. One thing I appreciate is the clean switching waveform with minimal ringing, which helps with EMI. The power-good indicator is useful for sequencing multiple rails. Overall, a solid choice for 3A applications where space is at a premium."
Excellent 3A buck converter with 2.5MHz frequency for compact designs
— Michael Chen, BeiLuo
Frequently Asked Questions
What is the maximum output current of XZ2105?
The XZ2105 can deliver up to 3A continuous output current with proper thermal management. The actual maximum current may be limited by thermal considerations depending on ambient temperature and PCB design. Peak current capability is higher for transient loads.
Design for 20-30% current margin below maximum rating for reliable operation; ensure adequate PCB copper area for heat dissipation.
What inductor value should I use with XZ2105?
For XZ2105's 2.5MHz switching frequency, a 1.0μH to 1.5μH inductor is recommended. Lower inductance values enable faster transient response but result in higher ripple current. Use inductors with saturation current rating at least 1.3 times the maximum load current.
Start with 1.0μH for typical applications; use 0.47μH for fastest transient response or 2.2μH for lowest ripple.
How do I set the output voltage?
Output voltage is set using a resistive divider from VOUT to FB pin to GND. The feedback reference voltage is 0.6V. Calculate R1 (top resistor) and R2 (bottom resistor) using: VOUT = 0.6V × (1 + R1/R2). Use 1% tolerance resistors for accurate output voltage.
Choose resistor values in the 10kΩ to 1MΩ range; lower values improve noise immunity but increase quiescent current.
What input and output capacitors are recommended?
For input, use 10μF to 22μF ceramic capacitors with X5R or X7R dielectric rated for the input voltage. For output, use 22μF to 47μF ceramic capacitors. Low ESR is important for stability and ripple performance. Place capacitors close to the IC pins.
Use ceramic capacitors with X7R dielectric for best temperature stability; add electrolytic capacitor for additional bulk capacitance if needed.
How do I use the power-good (PG) output?
The PG output is an open-drain signal that goes high impedance when the output voltage is within regulation. Connect a 100kΩ pull-up resistor to a logic voltage (1.8V, 3.3V, or 5V). PG can be used for power sequencing, reset generation, or monitoring.
Use PG for power sequencing in multi-rail systems; connect to processor reset input for power-on reset generation.