SGM6601
High-efficiency buck converter with 1.5MHz switching, 1A output current, and input voltage range of 2.5V to 5.5V.
Product Overview
Description
The SGM6601 is a high-efficiency synchronous step-down DC-DC converter designed for portable applications.
With a 1.5MHz switching frequency, it allows the use of small external components including chip inductors.
The device delivers up to 1A output current with peak efficiency exceeding 95%.
Product Series
SGM
Primary Application
Smartphones and tablets
Key Features
- High efficiency up to 95%
- 1.5MHz switching frequency
- 1A maximum output current
- Low quiescent current: 40uA
- 100% duty cycle for low dropout
Specifications
| Input Voltage | 2.5V - 5.5V |
|---|---|
| Output Voltage | 0.6V - Vin |
| Output Current | 1A |
| Switching Frequency | 1.5MHz |
| Efficiency | Up to 95% |
| Package | SOT-23-5, DFN-2x2-6 |
Applications
Smartphones and tablets
Electronic system design
Portable media players
Electronic system design
Wireless communication
Communication and interface
Battery-powered equipment
Battery and charging management
Industrial control systems
Industrial automation and control
FAE Expert Insights
"The SGM6601 is an excellent choice for single-cell Li-ion powered applications requiring efficient voltage conversion. In my experience with portable device designs, the 1.5MHz switching frequency allows use of compact 2.2uH chip inductors, significantly reducing board space compared to lower-frequency alternatives. The efficiency curve is well-optimized for the typical load range of portable electronics. I recommend using X5R or X7R ceramic capacitors for input and output filtering to maintain performance across temperature. For noise-sensitive applications, add an additional LC filter on the output."
Compact and efficient solution for portable power applications
— Robert Liu, BeiLuo
Frequently Asked Questions
What is the efficiency of the SGM6601 at light loads?
The SGM6601 maintains good efficiency across the load range. At light loads (10mA), efficiency is typically around 85%, increasing to over 95% at mid-to-heavy loads (200-500mA). The device features automatic power-save mode at light loads to maintain efficiency. For ultra-light load applications (below 1mA), consider using the PFM mode if available, or add a load resistor to keep the converter in continuous conduction mode for better transient response.
The SGM6601 is efficient across typical portable device load ranges. Review efficiency curves for your specific operating points.
What external components are required for the SGM6601?
The SGM6601 requires minimal external components: 1) Input capacitor: 10uF ceramic (X5R or X7R) close to the IC; 2) Output capacitor: 10uF ceramic for stability and transient response; 3) Inductor: 2.2uH with current rating exceeding maximum load current; 4) Optional: feedforward capacitor for improved transient response. All capacitors should have low ESR for best performance. The inductor should have saturation current at least 1.5x the maximum load current. Refer to the datasheet for specific component recommendations and PCB layout guidelines.
Use recommended component values from the datasheet. Contact our FAE team for BOM optimization assistance.
Can the SGM6601 operate at 100% duty cycle?
Yes, the SGM6601 supports 100% duty cycle operation, which means the high-side switch can remain on continuously. This feature is important for maintaining regulation when the input voltage approaches the output voltage (low dropout operation). In 100% duty cycle mode, the output voltage equals the input voltage minus the voltage drop across the high-side MOSFET and inductor DCR. This ensures continuous operation even when the battery voltage drops close to the required output voltage.
The 100% duty cycle capability is ideal for battery applications where input voltage varies. Ensure inductor current rating is sufficient.
What is the switching frequency of the SGM6601 and can it be adjusted?
The SGM6601 operates at a fixed 1.5MHz switching frequency. This frequency is internally set and cannot be adjusted externally. The 1.5MHz frequency was selected as an optimal balance between component size, efficiency, and EMI. Higher frequencies allow smaller inductors and capacitors but increase switching losses. Lower frequencies improve efficiency but require larger external components. The fixed frequency simplifies design and ensures predictable EMI performance. For applications requiring frequency synchronization, consider other SGMICRO products with external clock input.
The fixed 1.5MHz frequency is suitable for most portable applications. Contact us for alternatives if frequency synchronization is required.
How do I calculate power dissipation in the SGM6601?
Power dissipation in the SGM6601 can be calculated as: Pd = (Vin - Vout) x Iout x (1/Efficiency) - Vout x Iout. Alternatively, Pd = Vout x Iout x (1/Efficiency - 1). For example, with Vin=3.7V, Vout=1.8V, Iout=500mA, and 93% efficiency: Pd = 1.8V x 0.5A x (1/0.93 - 1) = 68mW. This low dissipation allows operation without heatsinking in most applications. For thermal calculations, use the thermal resistance from the datasheet and ensure junction temperature stays below the maximum rating.
Calculate power dissipation for your operating conditions. The SGM6601 typically runs cool without additional heatsinking.