BD6062GU_11 ROHM [Rohm], BD6062GU_11 Datasheet - Page 14

• Manufacturer Part Number: BD6062GU_11
• Description: Chopper type for Flash
• Manufacturer: ROHM [Rohm]

© 2011 ROHM Co., Ltd. All rights reserved.
www.rohm.com
BD6062GU
( 6 )
( 7 )
( 8 )
( 9 )
( 10 ) Ground wiring pattern
( 11 ) External capacitor
( 12 ) Thermal shutdown circuit (TSD)
( 13 ) Thermal design
( 14 ) Selection of coil
In order to mount ICs on a set PCB, pay thorough attention to the direction and offset of the ICs. Erroneous mounting
can break down the ICs. Furthermore, if a short circuit occurs due to foreign matters entering between terminals or
between the terminal and the power supply or the GND terminal, the ICs can break down.
Be noted that using ICs in the strong electromagnetic field can malfunction them.
On the inspection with the set PCB, if a capacitor is connected to a low-impedance IC terminal, the IC can suffer stress.
Therefore, be sure to discharge from the set PCB by each process. Furthermore, in order to mount or dismount the set
PCB to/from the jig for the inspection process, be sure to turn OFF the power supply and then mount the set PCB to
the jig. After the completion of the inspection, be sure to turn OFF the power supply and then dismount it from the jig. In
addition, for protection against static electricity, establish a ground for the assembly process and pay thorough attention
to the transportation and the storage of the set PCB.
In terms of the construction of IC, parasitic elements are inevitably formed in relation to potential. The operation of the
parasitic element can cause interference with circuit operation, thus resulting in a malfunction and then breakdown of
the input terminal. Therefore, pay thorough attention not to handle the input terminals, such as to apply to the input
terminals a voltage lower than the GND respectively, so that any parasitic element will operate. Furthermore, do not
apply a voltage to the input terminals when no power supply voltage is applied to the IC. In addition, even if the power
supply voltage is applied, apply to the input terminals a voltage lower than the power supply voltage or within the
guaranteed value of electrical characteristics.
If small-signal GND and large-current GND are provided, It will be recommended to separate the large-current GND
pattern from the small-signal GND pattern and establish a single ground at the reference point of the set PCB so that
resistance to the wiring pattern and voltage fluctuations due to a large current will cause no fluctuations in voltages of
the small-signal GND. Pay attention not to cause fluctuations in the GND wiring pattern of external parts as well.
In order to use a ceramic capacitor as the external capacitor, determine the constant with consideration given to a
degradation in the nominal capacitance due to DC bias and changes in the capacitance due to temperature, etc.
When junction temperatures become 175℃ (typ) or higher, the thermal shutdown circuit operates and turns a switch
OFF. The thermal shutdown circuit, which is aimed at isolating the LSI from thermal runaway as much as possible, is
not aimed at the protection or guarantee of the LSI. Therefore, do not continuously use the LSI with this circuit
operating or use the LSI assuming its operation.
Perform thermal design in which there are adequate margins by taking into account the permissible dissipation (Pd) in
actual states of use.
Select the low DCR inductors to decrease power loss for DC/DC converter.
Short circuit between terminals and erroneous mounting
Operation in strong electromagnetic field
Inspection with set PCB
Input terminals
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Technical Note
2011.05 - Rev.B