R1276 Series
3A 30V Input Step-down DC/DC Converter with Synchronous Rectifier
R1276 Series
3A 30V Input Step-down DC/DC Converter with Synchronous Rectifier
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Provides at-a-glance product features, functions, and concepts.
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Description
The R1276 is a 36-V rated synchronous step-down DC/DC converter with built-in transistor. Under cranking condition, the switching frequency is automatically reduced to keep output voltage level constant.
Key Benefits
- High efficiency of 95%
- Maintains the output voltage constant at cranking by reducing a switching frequency to the minimum 1/4.
- Achieves the EMI noise reduction by using a spread spectrum clock generator. (Diffusion Rate: +10%).
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 125°C (150°C) | -40°C to 125°C (150°C) |
| Supply Current | Typ. 12 µA (VFM, at no switching) | ||
| Standby Current | Typ. 4 µA | ||
| Start-up Voltage | 4.5 V | ||
| Output Voltage Range | Externally Adjustable: 0.7 V to 6.5 V | ||
| Feedback Voltage | 0.64 V | ||
| Feedback Voltage Accuracy | ±1.0% | ||
| Output Current | 3 A | ||
| Driver ON-resistance | High-side: Typ. 0.145 Ω Low-side: Typ. 0.095 Ω |
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| Oscillator Frequency | 250 kHz to 1 MHz (Settable with external resistors)*1 | ||
| Efficiency | 95% | ||
| Package | HSOP-18 | ||
- *1: In the case of 0.7 V ≤ VOUT < 3.3 V, the configurable range is 250 kHz ≤ fOSC ≤ 600 kHz.
Protections / Functions
| TSD | OCP | OVP | UVLO | OVLO | Reverse | Shutdown | Soft Start | SSCG | PGOOD | Auto Discharge | Anti-ringing | Sequencing | Max Duty | Ext. Phase | LED Adjust |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Functional Description
| TSD | Thermal Shutdown Function |
|---|---|
| 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
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Efficiency Characteristics (VOUT = 5V)

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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
R1276 Series


