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BD2046AFJ BD2056AFJ
Datasheet
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TSZ22111･15･001
TSZ02201-0E3E0H300140-1-2
11.Mar.2013 Rev.001
(10) GND wiring pattern
When using both small-signal and large-current GND traces, the two ground traces should be routed separately but
connected to a single ground at the reference point of the application board to avoid fluctuations in the small-signal
ground caused by large currents. Also ensure that the GND traces of external components do not cause variations on the
GND voltage. The power supply and ground lines must be as short and thick as possible to reduce line impedance.
(11) External Capacitor
When using a ceramic capacitor, determine the dielectric constant considering the change of capacitance with
temperature and the decrease in nominal capacitance due to DC bias and others.
(12) Thermal shutdown circuit (TSD)
The IC incorporates a built-in thermal shutdown circuit, which is designed to turn off the IC when the internal temperature
of the IC reaches a specified value. Do not continue to operate the IC after this function is activated. Do not use the IC in
conditions where this function will always be activated.
(13) Thermal consideration
Use a thermal design that allows for a sufficient margin by taking into account the permissible power dissipation (Pd) in
actual operating conditions. Consider Pc that does not exceed Pd in actual operating conditions (Pc≥Pd).
Package Power dissipation : Pd (W)=(Tjmax－Ta)/θja
Power dissipation : Pc (W)=(Vcc－Vo)×Io+Vcc×Ib
Tjmax : Maximum junction temperature=150℃, Ta : Peripheral temperature[℃] ,
θja : Thermal resistance of package-ambience[℃/W], Pd : Package Power dissipation [W],
Pc : Power dissipation [W], Vcc : Input Voltage, Vo : Output Voltage, Io : Load, Ib : Bias Current
