15/22
BD2046AFJ BD2056AFJ
Datasheet
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TSZ22111･15･001
TSZ02201-0E3E0H300140-1-2
11.Mar.2013 Rev.001
●Typical Application Circuit
ON/OF
OC
OC
ON/OF
ND
IN
/EN1
(EN1)
/OC1
OUT1
OUT2
/OC2
10k to 100k
5V(Typ)
OU
IN
VBUS
D+
D-
GND
Data
Regulator
USB Controller
BD2046AFJ/56AFJ
C
Data
/EN2
(EN2)
10k to 100k
CIN
Data
C
●Application Information
When excessive current flows due to output short-circuit or so, ringing occurs because of inductance between power source
line to IC, and may cause bad influences on IC operations. In order to avoid this case, connect a bypass capacitor across
IN terminal and GND terminal of IC. 1μF or higher is recommended.
Pull up /OC output by resistance of 10kΩ to 100kΩ.
Set up value which satisfies the application as C
L.
This application circuit does not guarantee its operation.
When using the circuit with changes to the external circuit constants, make sure to leave an adequate margin for external
components including AC/DC characteristics as well as dispersion of the IC.
●Functional Description
1. Switch operation
IN terminal and OUT terminal are connected to the drain and the source of switch MOSFET respectively. The IN terminal
is used also as power source input to internal control circuit.
When the switch is turned on from EN/EN control input, the IN terminal and OUT terminal are connected by a 100mΩ
switch. In ON status, the switch is bidirectional. Therefore, when the potential of OUT terminal is higher than that of the
IN terminal, current flows from OUT terminal to IN terminal.
Since a parasitic diode between the drain and the source of switch MOSFET is canceled, in the off status, it is possible
to prevent current from flowing reversely from OUT to IN.
2. Thermal shutdown circuit (TSD)
Thermal shutdown circuit have dual thermal shutdown threshold. Since thermal shutdown works at a lower junction
temperature when an overcurrent occurs, only the switch of an overcurrent state become off and error flag is output.
Thermal shut down action has hysteresis. Therefore, when the junction temperature goes down, switch on and error flag
output automatically recover. However, until cause of junction temperature increase such as output short circuit is
removed or the switch is turned off, thermal shutdown detection and recovery are repeated. The thermal shutdown circuit
works when the switch of either OUT1 or OUT2 is on (EN,/EN signal is active).
