High Efficiency, Fast Response, 6A, 28V Input Synchronous Buck Converter
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- Parameters
- Features
- Description
| Part number | SY21286RHC |
|---|
| Channel(#) | 1 |
|---|
| Vin (min) (V) | 4.5 |
|---|
| Vin (max) (V) | 24 |
|---|
| Switching frequency (min)(kHz) | 500 |
|---|
| Switching frequency (max)(kHz) | 500 |
|---|
| Vout (min) (V) | 0.6 |
|---|
| Vout (max) (V) | 2.5 |
|---|
| Iout (max) (A) | 6 |
|---|
| Vout2 (min)(V) | |
|---|
| Vout2 (max )(V) | |
|---|
| Iout2 (max)(A) | |
|---|
| Vref accuracy (±%) | 1 |
|---|
| Vout accuracy(±%) | |
|---|
| Control mode | COT+Ripple |
|---|
| Duty cycle (max)(%) | 80 |
|---|
| Operation mode | Auto PFM |
|---|
| Iq (typ) (uA) | 190 |
|---|
| Features | Power good,Output discharge, programmable current limit, Latch-off SCP |
|---|
| Package | QFN2.5×2.5-16 |
|---|
| Operating temperature range(°C) | -40 to 125 |
|---|
| Functional safety category | |
|---|
- Low RDS(ON) for Internal MOSFETs: 28mΩ Top, 16mΩ Bottom
- Wide Input Voltage Range: 4.5V ~ 24V
- Adjustable Output Voltage: 0.6V ~ 2.5V
- 6A Continuous Output Current Capability
- 500kHz Pseudo-Constant Frequency
- ±1% Internal Reference Voltage
- Internal 0.6ms Soft-Start Limits the Inrush Current
- Constant On-Time and Ripple-Based Control
- Excellent Dynamic Performance
- Integrated 1.2Ω Bypass Switch
- PFM/USM Selectable Light Load Operation Mode
- Power Good Indicator
- Output Auto-Discharge Function
- Adjustable Valley Current Limit Threshold by ILMT Pin
- Cycle-by-Cycle Peak and Valley Current Limit Protection
- Latch-Off Mode Output Under Voltage Protection
- Latch-Off Mode Output Over Voltage Protection
- Latch-Off Mode Over Temperature Protection
- Input Under Voltage Lockout (UVLO)
- RoHS Compliant and Halogen Free
- Compact package: QFN2.5×2.5-16
The SY21286 is a high efficiency synchronous buck converter operating over a wide input voltage range of 4.5V to 24V and capable of delivering up to 6A current. It integrates low RDS(ON) top and bottom MOSFETs to minimize the conduction loss. It operates at a pseudoconstant frequency of 500kHz, to enable the use of small size inductor and capacitors. The SY21286 also integrates a bypass switch which allows the VCC to be powered by external 3.3V power supply and further reduces the power consumption of the entire system.
Silergy’s constant on-time and ripple-based control strategy supports high input/output voltage ratios (low duty cycles), and fast transient response while maintaining a near constant operating frequency over line, load and output voltage ranges. This control method provides stable operation without complex compensation, including when using low ESR output ceramic capacitors.
The SY21286 provides cycle-by-cycle current limit, input under voltage lockout, internal soft-start, output under voltage protection, over voltage protection and over temperature protection, to guarantee safe operation in all operating conditions.
Evaluation Board
Photo of evaluation board
Photo of evaluation board
Photo of evaluation board
Photo of evaluation board
Photo of evaluation board
The EVB_SY21286RHC is intended for evaluating 500kHz, 6A output current, 24V input synchronous buck converter.
