R1285L Series
2ch DCDC for OLED
The R1285L 2ch DC/DC converter is designed for OLED Display power source. It contains a step up DC/DC
converter and an inverting DC/DC converter to generate two required voltages by OLED Display.
Step up DC/DC converter generates boosted output voltage to 4.6V ~ 5.0V. Inverting DC/DC converter generates
negative voltage –2.0V ~ -6.0V independently. Each of the R1285 series consists of an oscillator, a PWM control
circuit, a voltage reference, error amplifiers, over current protection circuits, short protection circuits, an under
voltage lockout circuit (UVLO), a complete shutdown switch and an Nch driver for boost operation, a Pch driver for
inverting. A high efficiency boost and inverting DC/DC converter can be composed with external inductors, diodes,
capacitors and resistors. Start up sequence is internally made.
| Operating Voltage | 2.3V ~ 4.8V | |
| Step Up DC/DC (CH1) |
Internal Pch MOSFET for complete shutdown (Ron=300mΩTyp.) | |
| Internal Nch MOSFET Driver (Ron=300mΩTyp.) | ||
| Output Voltage (VOUTP) : | 4.6V ~ 5.0V (0.2VStep) | |
| Auto Discharge function for positive output | ||
| Internal Soft start function (Typ. 4.5ms) | ||
| Over Current Protection | ||
| Maximum Duty Cycle : | 85%(Typ.) | |
| Inverting DC/DC (CH2) |
Internal Pch MOSFET Driver (Ron=600mΩ Typ.) | |
| Output Voltage (VOUTN) : | -2V ~ -6V (0.1VStep) [ R1285LxxxA ] | |
| Adjustable Vout Up to -6V with external resistors [ R1285L00xB ] | ||
| Auto Discharge function for negative output | ||
| Internal Soft start function (Typ. 4.5ms) | ||
| Over Current Protection | ||
| Maximum Duty Cycle : | 90%(Typ.) | |
| Control | Short Protection with timer latch function (Typ. 50ms) |
Short condition for either or both two outputs makes all output drivers off and latches. If the maximum duty cycle continues for a certain time, these output drivers will be turned off. This function prevents irregular current from overheating the R1285. |
| CE with start up sequence function ( CH1→CH2 ) | ||
| UVLO function. | ||
| Operating Frequency : | 1400kHz | |
| Small package | DFN12 ( 2.7mm x 3.0mm ) | |
- ・Fixed voltage power supply for portable equipment
- ・Fixed voltage power supply for OLED
| Data Sheet | Flyer | Package Info. | Mark Info. | Quality Assurance Data |
| R1285L Series | R1285L Series | DFN2730- 12 | R1285L | Reliability |
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