R1211 Series
PWM Step-up DC/DC Controller
Description
The R1211 Series are low supply current CMOS-based PWM step-up DC/DC controllers. R1211 does not include an internal output transistor. By simply using a power MOS, an inductor, a diode, resistors, and capacitors as external components, a high-efficiency step-up DC/DC converter can be easily configured. R1211 is available in two versions: B/D versions with an internal phase compensation and A/C versions with adjustable phase compensation with an external capacitor and resistor. The oscillator frequency can be selected from 300kHz or 700kHz. The soft start function built into the controller is set to Typ. 10.5ms for 300kHz and to Typ. 9ms for 700kHz. The latch type protection circuit embedded into the device latches the external driver in the "OFF" state when the oscillator maximum duty cycle continues for a predetermined period of time setting by an external capacitor.
Spec
| Standard | Automotive | |
|---|---|---|
| Input Voltage Range | 2.5 V to 6 V (6.5 V) | |
| Operating Temperature Range | -40°C to 85°C (125°C) | |
| Supply Current | Typ. 600 µA | |
| Standby Current | Typ. 0 µA | |
| Output Voltage Temperature Coefficient | Typ. ±150ppm/°C | |
| Feedback Voltage | 1.0 V | |
| Feedback Voltage Accuracy | ±1.5% | |
| Oscillator Frequency | Typ. 300 kHz, Typ. 700 kHz | |
| Maximum Duty Cycle | Typ. 90% | |
| Package | SOT-23-6W | |
Protections / Functions
| TSD | ILX | 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 |
|---|---|
| ILX | LX Current Limit Function |
| OCP | Overcurrent Protection |
| 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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R1211x002A/C Typical Application
L: 10µH (002A), 22µH (002C)
C1: 4.7µF, C2: 0.22µF, C3: 10µF, C4: 680pF, C5: 2200pF
R3: 30kΩ, R4: 30kΩ -
R1211x002B/D Typical Application
L: 10µH (002B), 22µH (002D)
C1: 4.7µF, C2: 0.22µF, C3: 10µF, C4: 680pF
R3: 30kΩ -
R1211x002A Efficiency vs. Output Current
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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.
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