RAA23014x RAA23015x
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Preliminary Datasheet RAA23014x RAA23015x [Under Development] 28.6V Input, Step-Down DC/DC Converter + Battery Backup Description The RAA23014x and RAA23015x are 1CH step-down DC/DC converter, 7V to 28.6V input voltage range. Auto PFM mode makes devices low power operation at light load, so it makes a system lower power. The RAA23014x is suitable for battery backup system using lithium primary cell with built-in battery backup circuit. Features DC/DC Synchronous rectification type step-down DC/DC Auto PFM mode Battery backup circuit (RAA23014x) Input voltage range 7V to 28.6V Output voltage range 0.8V to 6V Maximum output current 3A Shutdown current 1uA (typ.) Switching frequency 1.1MHz (fixed) Soft start 2ms (fixed) Integrated power MOSFETs Discharge circuit Internal phase compensator Protection circuit Short circuit protection (latch type) Thermal shutdown circuit 165°C (typ.) Under voltage lockout circuit (recovery type) Package 16-pin HTSSOP (RAA23014x) 8-pin HLSOP (RAA23015x) Application Communication (Router, Home Gate Way, Radio, etc.) Industrial (Surveillance camera, Various controller, etc.) Building (Security device, Emergency device, Various controller, etc.) OA (Printer, Plane paper copier, etc.) Smart meter Smart home appliances And, usable various application Note: The information contained in this document is being issued in advance of the production cycle for the product. The parameters for the product may change before final production, or Renesas Electronics Corporation, at its own discretion, may withdraw the product prior to its production. A quality grade of the devices is “Standard”. Recommended applications are indicated below. Computers, office equipment, communications equipment, test and measurement equipment, audio and visual equipment, home electronic appliances, machine tools, personal electronic equipment, and industrial robots, etc.

Product Lineup Table Part number Type Step-down + BB Step-down + BB Step-down Step-down 0.8V to 6.0V (adjustable by external resistors) 3.3V(fixed) 5.0V(fixed) 0.8V to 6.0V (adjustable by external resistors) Circuit example RAA230143 (1CHDCDC + Battery Backup, VOUT set by external resistors) RAA230153 (1CHDCDC, VOUT set by external resistors)

Block Diagram RAA23014x (1CHDCDC + Battery backup, VOUT set by external resistors) Input Voltage

RAA23015x (1CHDCDC, VOUT set by external resistors) Input Voltage

Pin Function RAA23014x (1CHDCDC + Battery backup) Pin No. 1 2 3 4 VOUT FB VBB_IN VBB_OUT VOUT feedback Feedback resistor connection Battery connection Backup voltage output Device enable EN=“L” or open : Disable (shutdown) EN=”H” : Enable (operation) Auto PFM mode ON/OFF x_AutoPFM=”L” : Auto PFM mode (change automatically) PFM mode at light load PWM mode at heavy load x_AutoPFM=“H” : PWM mode (fixed) Internal power supply output (Connect 1uF capacitor between VREG and GND) Ground Ground Ground Ground Inductor connection Boot strap input (Connect 0.1uF capacitor between LX and Boost) Power...

Absolute Maximum Ratings (Unless otherwise specified, TA = 25°C) Parameter EN applied voltage FB applied voltage VOUT applied voltage x_AutoPFM applied voltage (RAA23014x) VBB_IN applied voltage (RAA23014x) VOUT VOUT sink current (DC) When discharge circuit operation GND voltage Total power dissipation Operating ambient temperature Operating junction temperature Storage temperature Tstg -55 to +150 °C Note: T.B.D. :To be determined. *1 This is the value at TA < +25°C. At TA > +25°C, the total power dissipation decrease with -T.B.D. mW/°C. Caution: Product quality may suffer if the absolute...

Recommended Operating Condition (Unless otherwise specified, TA = 25°C) Parameter x_AutoPFM applied voltage FB applied voltage Output voltage VOUT set by external resistors *1 About rising time (tr) and falling time (tf) of input signal to EN1 and EN2 pins, when EN1 and EN2 pins are not connected to power supply pin (VIN), set tr and tf less than 100ms. When EN1 and EN2 pins are connected to VIN pin, there are no restriction. *2 Output voltage (minimum value) 7.0 Output voltage area

Electrical Characteristics (Unless otherwise specified, TA = 25°C, VIN = 24V) Parameter Total Shutdown current Under voltage lock out circuit (UVLO) Internal power supply (VREG) Operating start voltage Operating stop voltage Internal power supply voltage Include input offset at external resistor setting Fixed VOUT products Output Output voltage accuracy (PWM mode) High side FET on-resistance Vacc Ronh Discharging On resistance Circuit block Soft start Thermal shutdown circuit Soft start time*1 Detect temperature Hysteresis temperature High level threshold voltage Low level threshold voltage...

Typical Performance Characteristics (Unless otherwise specified, TA = 25°C) Efficiency vs. Output Current VOUT=5.0 V, Auto PFM mode

Detailed Description Control Block EN : ON/OFF setting EN state L Shutdown H Operation Note: L: Low level, H: High level x_autoPFM : AutoPFM mode/ PWM mode setting (only RAA23014x) x_autoPFM L Auto PFM mode (change automatically) PFM mode at light load PWM mode at heavy load H PWM mode (fixed) Note: L: Low level, H: High level

RAA23014x and RAA23015x have Auto PFM mode to achieve high efficiency over a wide load current range. The devices operate with PFM (Pulse Frequency Modulation) mode at light load current, and PWM (Pulse Width Modulation) mode at heavy load current. An operation mode is automatically switched depending on load current. When a bottom of inductor ripple current is under OA, reverse current flow at low-side N-channel MOSFET of output block. The devices operate with PFM mode during detecting this current. A current of switching PFM / PWM mode (Fhange) is calculated by an equation below. Reverse...

Soft Start To limit the startup inrush current and output voltage overshoot, a soft start circuit is used to ramp up the reference voltage from 0 V to its final value linearly. When EN pin is set from low level to high level, the device starts operation and output voltage rises with soft start. Soft start time are fixed at 2ms(Typ.) and no additional components are needed. Soft start feature gradually increases the error amplifier (E/A) input threshold voltage by using the voltage that is generated by the digital soft start (DSS) circuit. Note1 : This figure is the case of RAA230143 or...