BD9995NUV_11 Datasheet, PDF (4/5 Pages) Rohm – Silicon monolithic integrated circuits

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○Operation Notes
1．About ground potential
・.The ground line is where the lowest potential and transient voltages are connected to the IC. Moreover, all terminals except
the terminal GND must not become the voltage of GND or less actually including transients.
2．About starting
・Keep light Load at VOUT output while start-up.
3．About board pattern
・ Use separates ground lines for small control signals and high current outputs. Because these high current outputs that
flows to the wire impedance changes the GND voltage for control signal. Therefore each ground of IC must be connected
at one point on the set circuit board. As for GND of external parts, it’s similar to the above-mentioned.
4．About peripheral circuit
・ Bypass capacitor between power supply and ground should be use low ESR ceramic capacitor and placed close to the IC
pin as possible. The output condenser is necessary to be placed as near to the IC as possible with shortest distance.
Monitor the output voltage at both end of capacitor connected to VOUT.
5．About absolute maximum rating
・ Exceeding supply voltage and operating Temp. over Absolute Maximum Ratings may cause degradation of IC and even
may destroy the IC. If special mode such that exceeding Absolute Maximum Ratings is expected, please have safe
countermeasure such as adding POLY SWITCH and fuse to avoid from over stressing.
6．About heat design
・ Do not exceed the power dissipation (PD) of the package specification rating under actual operation.
7．About Short between pins and the mis-installation
・ While mounting IC on the printing board, check direction and position of the IC. If inadequately mounted, the IC may destroy.
Moreover this IC might be destroyed when dust short the terminals between pins or pin and ground.
8．About operation in strong electromagnetic field
・ Strong electromagnetic radiation can cause operation failures.
9．About heat interception circuit (TSD)
・ The heat interception circuit is built into this IC. When the junction temperature (Tj) reaches 175℃, the output is switched
to off. It is a circuit to aim to intercept IC from thermal reckless driving to the last, and it aims at no protection and the
guarantee of neither set nor IC. Therefore, operate this circuit and use neither continuous use from now on nor operation.
10．About over current protection circuit
・ The over current protection circuit is built into this IC. It operates by the effective one of the protection circuit continuous
for the destruction prevention due to broken accident, and avoids the load about this circuit about use to which the
operation of this function is required because it is not the one to the use when it is excessive IC destruction.
11．About inspection by set substrate
・ The stress might hang to IC by connecting the capacitor to the terminal with low impedance. Then, please discharge
electricity in each and all process. Moreover, in the inspection process, please turn off the power before mounting the IC,
and turn on after mounting the IC. In addition, please take into consideration the countermeasures for electrostatic damage,
such as giving the earth in assembly process, transportation or preservation.
12．About each input terminal
・ This IC is a monolithic IC, and has P⁺ isolation and P substrate for the element separation. Therefore, a parasitic PN junction
is firmed in this P-layer and N-layer of each element. When the GND voltage potential is greater than the voltage potential
at Terminals A or B, the PN junction operates as a parasitic diode. In addition, the parasitic NPN transistor is formed in said
parasitic diode and the N layer of surrounding elements close to said parasitic diode. These parasitic elements are formed in
the IC because of the voltage relation. The parasitic element operating causes the wrong operation and destruction.
Therefore, please be careful so as not to operate the parasitic elements by impressing to input terminals lower voltage than
GND (P substrate). Please do not apply the voltage to the input terminal when the power –supply voltage is not impressed.
Moreover, please impress each input terminal lower than the power-supply voltage or equal to the specified range in the
guaranteed voltage when the power-supply voltage is impressing.
REV. B