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CXSU63305: Industrial grade high-voltage boost DC-DC power management chip

CXSU63305 is a product designed specifically forHigh voltage and high current scenariosDesigned synchronous rectification boost DC-DC chip, supporting4-20V wide voltage inputand600V ultra-high output voltageIts innovative architecture integrates half bridge drive and intelligent protection functions, and is widely used in high reliability fields such as electric bicycle converters and industrial control systems.XXf嘉泰姆

Core performance breakthrough

1. High voltage output capabilityXXf嘉泰姆

a. Support600V ultra-high output voltage(VB pin withstand voltage)XXf嘉泰姆

b. 4-20V wide input range (VCC pin), suitable for battery/industrial power supplyXXf嘉泰姆

c. External single capacitor frequency modulation(CP pin): Frequency range 0-300kHz (formula: f=18×); 10⁶/Cp）XXf嘉泰姆

2. Intelligent control featuresXXf嘉泰姆

a. Dual mode enable control：XXf嘉泰姆

b. Weekly flow restriction protection：XXf嘉泰姆

3. High integration designXXf嘉泰姆

a. Built in3.3V reference source(REF3.3V pin, 50mA driving capability)XXf嘉泰姆

b. SOP16 Compact Package (10.0× 6.3mm)XXf嘉泰姆

c. Soft start (SS pin)/emergency shutdown (SD pin) dual safety mechanismXXf嘉泰姆

Key Application Design Guidelines

Key points of circuit designXXf嘉泰姆

1. Frequency setting(CP pin):XXf嘉泰姆

Using 270pF capacitor→ 67kHz typical frequency (Δ f/Δ Vcc≤± 5%)XXf嘉泰姆

2. Output voltage configuration(FB pin):XXf嘉泰姆

Example: R1=200kΩ , R2=10kΩ → 25.2V outputXXf嘉泰姆

3. Inductance selection(Continuous/Discontinuous Mode):XXf嘉泰姆

Suggested ripple current: 30% I ₒᵤₜₘₐₓXXf嘉泰姆

PCB layout specificationsXXf嘉泰姆

Performance advantages in industrial scenarios

▶Deep optimization of protection mechanismXXf嘉泰姆

1. Short circuit responseReal time monitoring with SDHIN/SDLIN dual comparator (180mV threshold)XXf嘉泰姆

2. Overheating protectionOperating at 125 ℃ ambient temperature limitXXf嘉泰姆

3. Under voltage locking: VCC on/off threshold 3.65V/3.6V (± 2% accuracy)XXf嘉泰姆

Design warningVB-VS pressure difference>20V may damage the chip! It is recommended to use SiC MOS transistors in high-voltage scenarios to reduce internal resistance.XXf嘉泰姆

 Application Design Circuit Component Parameter SelectionXXf嘉泰姆

1   REF3.3V input capacitorXXf嘉泰姆

      Placing a high-frequency small capacitance bypass capacitor to ground at the REF3.3V pin will reduce high-frequency noise at the REF3.3V terminal. The high-frequency bypass capacitor is optionalXXf嘉泰姆
Use a 0.1uF ceramic capacitor and place the PCB as close as possible to the chip pin REF3.3V input terminal.XXf嘉泰姆

2   VCC energy storage capacitorXXf嘉泰姆

      CXSU63305 requires placing a 10uF surface mount ceramic capacitor or a 0.1uF ceramic capacitor in parallel with a 10uF electrolytic capacitor at the VCC pin end to ground, and placing the PCB board as close as possible to the chip pins.XXf嘉泰姆

3   Start off voltageXXf嘉泰姆

      2-pin external resistor can adjust the startup voltage and shutdown voltageXXf嘉泰姆
Starting voltage calculation formula: 1.2V x (R20+R21)/R21+18uA * R20XXf嘉泰姆
Calculation formula for closing voltage: 1.2V x (R20+R21)/R21XXf嘉泰姆

4   Calculation of Switching Frequency of Cp Capacitor in OscillatorXXf嘉泰姆

      CXSU63305   Only one external capacitor is needed to set the PWM operating frequency, and a constant current source is used internally to charge and discharge the Cp capacitor as shown in Figure 8.4a,XXf嘉泰姆
The constant current source for injecting current provides approximately 36uA of current internally to charge the Cp capacitor, while the constant current source for pulling current provides approximately 720uA of current internallyXXf嘉泰姆
The current discharges the CT capacitor, and the approximate relationship between the operating frequency and capacitance is given by the formula f=(18 x10^six）/Cp is determined (the capacitance unit of this formula is pF), for example, a capacitance of Cp=270pF corresponds to a PWM operating frequency of approximately 67KHz.XXf嘉泰姆
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5   Output peak current limitXXf嘉泰姆

      CXSU63305   The peak current limit of the high-end output of the chip is determined by the internal resistance of the high-end MOS transistor, and the relationship between peak current and IPK is 180mV/XXf嘉泰姆
(High end MOS tube internal resistance); The peak current limit of the low-end output of the chip is determined by the series resistance R7 of the low-end MOS transistor, and the relationship between the peak current and R7 is givenXXf嘉泰姆
It is IPK=180mV/R7.XXf嘉泰姆
Low end current limit value after harmonic compensation:XXf嘉泰姆
IPK=（180mV-2*R6/(R6+R24)）/R7XXf嘉泰姆

6   Output inductanceXXf嘉泰姆

      CXSU63305   There are two working modes: continuous working mode and discontinuous working mode. The value of the inductance will affect the working mode of the boosterXXf嘉泰姆
When under light load, CXSU63305 operates in discontinuous mode, and the inductance value will affect the ripple of the inductance current. The selection of inductance can be based on the following formula:XXf嘉泰姆
In the equation, Vin is the input voltage, Vout is the output voltage, and Vdiode is the conduction of the synchronous rectification MOS transistorXXf嘉泰姆
Voltage difference, Fs is the PWM operating frequency, and Iripple is the peak to peak value of current ripple in the inductor. Typically, Iripple is selected to not exceed 30% of the maximum output current.XXf嘉泰姆

7   Synchronous rectification MOS transistorXXf嘉泰姆

      Adopting synchronous rectification MOSFET; Replacing traditional asynchronous converters with freewheeling diodes greatly improves power conversion efficiency; synchronous rectificationXXf嘉泰姆
MOSFET selection with low internal resistance and low junction capacitance can provide good performance for CXSU63305 booster.XXf嘉泰姆

8   output capacitorXXf嘉泰姆
      The output capacitor Co is used to filter the output voltage, so that the DC-DC booster outputs a relatively stable DC power to the loadXXf嘉泰姆
When selecting capacitors, try to choose capacitors with low ESR as much as possible. The size of the selected capacitor value is mainly determined by the ripple requirements of the output voltage, which can be determined by the following formula:XXf嘉泰姆
In the formula, Delta; Vo is the output voltage ripple,Δ IL is the inductor current ripple, Fs is the PWM operating frequency, and ESR is the output currentXXf嘉泰姆
Equivalent series resistance of capacitance.XXf嘉泰姆
9     Output voltage regulation settingXXf嘉泰姆
      The output voltage of CXSU63305 is set by two voltage divider resistors on the FB pin, and the reference voltage of the internal error amplifier is 1.2V, as shown in Figure 8.10aXXf嘉泰姆
As shown, the output voltage Vout=(1+R1/R2) * 1.2V. If you need to set the output voltage to 25.2V, you can set R1 to 200K and R2 to 10KXXf嘉泰姆
Output voltage Vout=(1+200/10) * 1.2V=25.2V.XXf嘉泰姆

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Summary:CXSU63305 passedSingle capacitor frequency modulation, dual path current limiting, and 600V withstand voltageThree major technological breakthroughs provide cost-effective solutions for high-voltage boost conversion, significantly reducing system complexity and BOM costs. Its synchronous rectification architecture improves efficiency by 8% -12% compared to traditional diode solutions, making it an ideal choice for industrial power supply design.XXf嘉泰姆

      For detailed PDF specifications, please contact us. You can also receive free samples and technical support！XXf嘉泰姆
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   Product packaging diagram XXf嘉泰姆

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   circuit schematic diagram XXf嘉泰姆

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   Selection Guide for Related Chips                  More similar products .....XXf嘉泰姆

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