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Terminal voltage input sequence

Characteristics of output voltage

Output current

Output terminal applied (short / voltage / current)

Input / output reversal (voltage / current)

Output capacitor

Detection and restriction of overcurrent protection (OCP)

EN (CTL, STBY, CE) terminal

Reduced voltage detection (UVLO / LVCC)

FAQ's

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Why isn't the current output even when the switch is ON in high-side and low-side switch ICs equipped with overcurrent detection circuit where the output current value is set below the overcurrent detection value?
- If the switch is turned ON while connected to a load exceeding the overcurrent limit value (short-circuit output current), the output current is limited to the overcurrent limit value and not the overcurrent detection value. Turning ON the load after turning ON the switch makes it possible to output a current over the overcurrent limit value.

For high-side and low-side switch ICs, when a higher voltage is supplied to the OUT side than the IN side when the switch is OFF, will there be problems (i.e. backflow)?
- Backflow models:
  BD6538G、 BD2224G、 BD2225G、 BD2226G、 BD2227G、 BD2232G、 BD2233G、 BD6538G-LB、 BD2224G-LB、 BD2225G-LB、 BD2226G-LB、 BD2227G-LB、 BD2268G-M、 BD2269G-M、 BD82001FVJ、 BD82000FVJ、 BD82001FVJ-LB、 BD82000FVJ-LB、 BD82004FVJ-M、 BD82005FVJ-M、 BD2200GUL、 BD2201GUL、 BD2202G、 BD2206G、 BD6520F、 BD2202G-LB、 BD2206G-LB、 BUS1DJC0GWZ、 BUS1DJC3GWZ
  . With backflow models, if a higher voltage is supplied to OUT vs IN when the switch is OFF (EN=OFF), current may flow (i.e. through a parasitic diode), which can lead to deterioration and breakdown. If applying a higher voltage to OUT than IN, please use a model that can prevent backflow. Applicable models are described as providing 'reverse current protection while the switch is OFF' in the datasheet.
  Related Link：Technical Document

For high-side and low-side switch ICs, why isn't the expected voltage output even if the EN (/EN) pin of products with a built-in overcurrent detection circuit is enabled?
- If the switch turns ON when a resistive load exceeding the overcurrent limit (short-circuit output current) is connected, overcurrent is detected and the output current is immediately limited to the overcurrent limit value. The output voltage at this time is 'Overcurrent Limit Value (Short-Circuit Output Current) x Load Resistance Component'. Besides this, there is a possibility of a short-circuit between the output and ground.
  Related Link：Technical Document

Is there a problem with connecting a large capacitance capacitor (C_L, USB standard 120uF or more) to the output of high-side and low-side switch ICs?
- There should be no problems even if a large capacitance capacitor (USB standard, 120uF or more) is connected to the output. However, when the IC turns ON and the output rises the capacitor C_L is charged, causing inrush current to flow. Depending on the value of C_L, the inrush current is restricted to the current limit value and the IC enters an overcurrent detection state. If the high-side switch IC continues in this state for more than the /OC pin (flag) output delay time, 'L' is output from the /OC pin.

What is the recovery method for high-side and low-side switch ICs equipped with an overcurrent limiting circuit latch after current limit is applied and the latch is OFF?
- One recovery method involves turning OFF the EN (CTRL) pin and then turning it ON again or turning the power supply OFF then ON, or going below V_TUVL(V_UVLOL) then above V_TUVH(V_UVLOH).

Explain the operation of UVLO for high-side and low-side switch ICs.
- UVLO is a function that forcibly turns OFF when the IN pin voltage drops below the UVLO threshold. The threshold has upper and lower hysteresis, and both upper and lower sides are set below the operating supply voltage.

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