R1275 Series
2A 30V Input Forced PWM Step-down DC/DC Converter with Synchronous Rectifier
Description
The R1275 is a 36-V synchronous step-down DC/DC converter with built-in drivers. It is designed for industrial equipment, OA equipment and home electronics that require a 24-V input. It operates at a 2-MHz switching frequency, which allows to use a small inductor to ensure a high transient response and to maintain a high efficiency at heavy load condition. Using a spread spectrum clock generator, the EMI noise can be reduced. Under cranking condition, the switching frequency is automatically reduced to keep output voltage level constant.
- Provides a high switching frequency at 2 MHz with an efficiency of 87%.
- Maintains the output voltage constant by reducing a switching frequency to the minimum 1/4 when an input-output voltage difference is small.
- Achieves the EMI noise reduction by using a spread spectrum clock generator. (Diffusion Rate: +8%).
Spec
| Standard | Industrial | Automotive | |
|---|---|---|---|
| Input Voltage Range | 3.6 V to 30.0 V (36.0 V) | ||
| Operating Temperature Range | -40°C to 105°C (125°C) | -40°C to 105°C (125°C) | -40°C to 125°C (150°C) |
| Supply Current | Typ. 1 mA | ||
| Standby Current | Typ. 4 µA | ||
| Start-up Voltage | 4.5 V | ||
| Output Voltage Range | Externally Adjustable: 3.3 V to 5.0 V | ||
| Feedback Voltage | 0.64 V | ||
| Feedback Voltage Accuracy | ±1.0% | ||
| Output Current | 2 A | ||
| Driver ON-resistance | High side: Typ. 0.145 Ω, Low side: Typ. 0.095 Ω | ||
| Oscillator Frequency | Typ. 2 MHz | ||
| Package | HSOP-18 | ||
Protections / Functions
| TSD | OCP | OVP | UVLO | OVLO | Reverse | Shutdown | Soft Start | SSCG | PGOOD | Auto Discharge | Anti-ringing | Sequencing | Max Duty | Ext. Phase | LED Adjust |
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Functional Description
| TSD | Thermal Shutdown Function |
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| OCP | Overcurrent Protection Note: The function previously labeled as "ILX (LX Current Limit Function)" is now shown as "OCP." |
| OVP | Overvoltage Protection |
| UVLO | Undervoltage Lockout Protection |
| OVLO | Overvoltage Lockout Protection |
| Reverse | Reverse Current Protection Circuit |
| Shutdown | Shutdown Function |
| Soft Start | Soft Start Function |
| SSCG | Spread Spectrum Clock Generator Function |
| PGOOD | Power Good Output |
| Auto Discharge | Auto Discharge Function |
| Anti-ringing | Anti-ringing Switch Function |
| Sequencing | Start-up Sequencing Control |
| Max Duty | Maximum Duty Cycle |
| Ext. Phase | Externally Adjustable Phase Compensation |
| LED Adjust | LED High-speed Dimming Control |
Technical Documents
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Typical Application
*1) Connecting a Schottky barrier diode between LX and GND can reduce the LX noise and improve the efficiency.
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Efficiency (VOUT = 5 V)
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Related Links
Quality & Packages
- Refer to the datasheets for the details on the product.
- The package file or the datasheet includes package dimensions, taping specifications, taping reels dimensions, power dissipations, and recommended land pattern.
Qualification Test Plan (QTP) Sheets
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FAQ
Buy / Contact
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Purchase, Request for samples and documentsSales are made through distributors. Please contact your local distributors for any sales-related inquiry such as price.
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Available from 1 piece!Our electronic device products are available through our authorized online distributors.
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Technical Support