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BD7xxL5FP-C
9) Rapid variation in VCC voltage and load current
In case of a rapidly changing input voltage, transients in the output voltage might occur due to the use of a MOSFET as
output transistor. Although the actual application might be the cause of the transients, the IC input voltage, output current
and temperature are also possible causes. In case problems arise within the actual operating range, use
countermeasures such as adjusting the output capacitance.
10) Minute variation in output voltage
In case of using an application susceptible to minute changes to the output voltage due to noise, changes in input and
load current, etc., use countermeasures such as implementing filters.
11) Overcurrent protection circuit
This IC incorporates an integrated overcurrent protection circuit that is activated when the load is shorted. This protection
circuit is effective in preventing damage due to sudden and unexpected incidents. However, the IC should not be used in
applications characterized by continuous operation or transitioning of the protection circuit.
12) Thermal shutdown (TSD)
This IC incorporates and integrated thermal shutdown circuit to prevent heat damage to the IC. Normal operation should
be within the power dissipation rating, if however the rating is exceeded for a continued period, the junction temperature
(Tj) will rise and the TSD circuit will be activated and turn all output pins OFF. After the Tj falls below the TSD threshold
the circuits are automatically restored to normal operation.
Note that the TSD circuit operates in a situation that exceeds the absolute maximum ratings and therefore, under no
circumstances, should the TSD circuit be used in a set design or for any purpose other than protecting the IC from heat
damage.
13) In some applications, the VCC and pin potential might be reversed, possibly resulting in circuit internal damage or
damage to the elements. For example, while the external capacitor is charged, the VCC shorts to the GND. Use a
capacitor with a capacitance with less than 1000μF. We also recommend using reverse polarity diodes in series or a
bypass between all pins and the VCC pin.
14) This monolithic IC contains P+ isolation and P substrate layers between adjacent elements in order to keep them
isolated. P/N junctions are formed at the intersection of these P layers with the N layers of other elements to create a
variety of parasitic elements.
For example, in case a resistor and a transistor are connected to the pins as shown in the figure below then:
○ The P/N junction functions as a parasitic diode when GND > pin A for the resistor, or GND > pin B for the transistor.
○ Also, when GND > pin B for the transistor (NPN), the parasitic diode described above combines with the N layer of the
other adjacent elements to operate as a parasitic NPN transistor.
Parasitic diodes inevitably occur in the structure of the IC. Their operation can result in mutual interference between
circuits and can cause malfunctions and, in turn, physical damage to or destruction of the chip. Therefore do not employ
any method in which parasitic diodes can operate such as applying a voltage to an input pin that is lower than the
(P substrate) GND.
Resistor
Transistor (NPN)
B
(Pin A)
(Pin B)
(Pin B)
E
C
C
E
B
N
N
P
P
P+
P+
P+
P+
GND
N
N
P
N
N
N
Parasitic element
or transistor
P sub
GND
Parasitic
element
GND
(Pin A)
Parasitic element
or transistor
Parasitic
element
www.rohm.com
TSZ02201-T2T0AN00020-1-2
2.Oct.2012 Rev.001
© 2012 ROHM Co., Ltd. All rights reserved.
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TSZ22111・15・001
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