BD3507HFV_08 Datasheet, PDF (12/16 Pages) Rohm – Ultra Low Dropout Linear Regulators for PC Chipsets

●NOTE FOR USE
1.Absolute maximum ratings
For the present product, thoroughgoing quality control is carried out, but in the event that applied voltage, working
temperature range, and other absolute maximum rating are exceeded, the present product may be destroyed. Because it
is unable to identify the short mode, open mode, etc., if any special mode is assumed, which exceeds the absolute maximum
rating, physical safety measures are requested to be taken, such as fuses, etc.
2.GND potential
Bring the GND terminal potential to the minimum potential in any operating condition.
3. Thermal design
Consider permissible dissipation (Pd) under actual working condition and carry out thermal design with sufficient margin
provided.
4.Terminal-to-terminal short-circuit and erroneous mounting
When the present IC is mounted to a printed circuit board, take utmost care to direction of IC and displacement. In the
event that the IC is mounted erroneously, IC may be destroyed. In the event of short-circuit caused by foreign matter that
enters in a clearance between outputs or output and power-GND, the IC may be destroyed.
5.Operation in strong electromagnetic field
The use of the present IC in the strong electromagnetic field may result in maloperation, to which care must be taken.
6. Built-in thermal shutdown protection circuit
The present IC incorporates a thermal shutdown protection circuit (TSD circuit). The working temperature is 175°C
(standard value) and has a -15°C (standard value) hysteresis width. When the IC chip temperature rises and the TSD
circuit operates, the output terminal is brought to the OFF state. The built-in thermal shutdown protection circuit (TSD
circuit) is first and foremost intended for interrupt IC from thermal runaway, and is not intended to protect and warrant the IC.
Consequently, never attempt to continuously use the IC after this circuit is activated or to use the circuit with the activation of
the circuit premised.
7. Capacitor across output and GND
In the event a large capacitor is connected across output and GND, when Vcc and VIN are short-circuited with 0V or GND
for some kind of reasons, current charged in the capacitor flows into the output and may destroy the IC. Use a capacitor
smaller than 1000 μF between output and GND.
8.Inspection by set substrate
In the event a capacitor is connected to a pin with low impedance at the time of inspection with a set substrate, there is a
fear of applying stress to the IC. Therefore, be sure to discharge electricity for every process. As electrostatic measures,
provide grounding in the assembly process, and take utmost care in transportation and storage. Furthermore, when the
set substrate is connected to a jig in the inspection process, be sure to turn OFF power supply to connect the jig and be sure
to turn OFF power supply to remove the jig.
9. IC terminal input
The present IC is a monolithic IC and has a P substrate and P⁺ isolation between elements.
With this P layer and N layer of each element, PN junction is formed, and when the potential relation is
GND>terminal A>terminal B, PN junction works as a diode, and
Terminal B>GND terminal A, PN junction operates as a parasitic transistor.
The parasitic element is inevitably formed because of the IC construction. The operation of the parasitic element gives rise
to mutual interference between circuits and results in malfunction, and eventually, breakdown. Consequently, take utmost
care not to use the IC to operate the parasitic element such as applying voltage lower than GND (P substrate) to the input
terminal.
Pin A
N
N ^P+
Parasitic element
Resistor
Pin A
P
P⁺ _N
P substrate
GND
Transistor (NPN)
Pin B _C B
Pin B
E
Parasitic
element
N _P+
Parasitic element
N
P
P⁺ _N
P substrate
GND
GND
B
C
E
Parasitic
element
GND
Other adjacent elements
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