YB1901 Datasheet, PDF (9/12 Pages) YOBON TECHNOLOGIES,INC. – 2.0A High-Side Power Switch with Flag

YB1901
2.0A High-Side Power Switch with Flag
Thermal Considerations
The YB1901 is designed to deliver a
continuous load current. The maximum
limit is package power dissipation. At any
given ambient temperature, the maximum
package power dissipation can be
determined by the following equation:
P_D(MAX) = [ T_J(MAX) - T_A ] / θ_JA
Constraints for the YB1901 are maximum
junction temperature T_J(MAX) = 125℃, and
package thermal resistance, θ_JA =280℃/W.
The maximum continuous output current
for YB1901 depends on package power
dissipation and the R_DS(ON) of MOSFET at
T_J(MAX). Typical conditions are calculated
under normal ambient condition where T_A =
25℃. At 85℃, P_D(MAX) = 143mW. At T_A =
25℃, P_D(MAX) = 357mW.
The maximum current is calculated by the
following equation:
I_OUT < (P_D(MAX) / R_DS(MAX))^1/2
For example, if V_IN = 5V, R_DS(MAX) = 100mΩ
and T_A = 25℃, I_OUT(MAX) = 1.89A.
Thermal Shutdown is employed to protect
the device damage when temperature is
over 120℃.
PCB Layout Consideration
To maximize YB1901 performance, some
board layout rules should be followed:
V_IN and V_OUT should be routed using wider
than normal traces, and GND should be
connected to a ground plane. For best
performance, C_IN and C_OUT should be
placed close to the package pins.
YB1901 Rev.1.2
www.yobon.com.tw
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