YB1900
Ultra Low Quiescent Current Smart Load Switch
Function Block
Application Information
The YB1900 featured very low quiescent
current and very low R
DS(ON)
and making
them ideal for battery-powered applications.
The ENABLE control pin is TTL compatible
and driven by 1.5V beyond making the
YB1900 an ideal level-shifting load switch.
Under normal conditions, there is a parasitic
diode between the output & input of the load
switch. In case of V
OUT
exceeding V
IN
, this
would forward bias the internal parasitic
diode and allow excessive current flow into
the V
OUT
pin and possibly damage the load
switch.
In applications, where there is a possibility of
V
OUT
exceeding V
IN
for brief periods of time
during operation, the use of larger value C
IN
capacitor is highly recommended. A larger
value of C
IN
with respect to C
OUT
will affect a
slower C
IN
decay rate during shutdown, thus
preventing V
OUT
from exceeding V
IN
.
In case of extended period of time for V
OUT
exceeding V
IN
, it is recommended to place a
Schottky diode from V
IN
to V
OUT
.
Input Capacitor Selection
A 1μF or larger input capacitor is
recommended to prevent load transients
from affecting upstream circuits. C
IN
should
be located as close to the device V
IN
pin as
practically. There is no specific requirement
type of capacitor is recommended. However,
for higher current operation, ceramic
capacitors are recommended for C
IN
.
Output Capacitor Selection
For proper slew operation, a 0.1μF or greater
is recommended. The output capacitor has
also no specific capacitor type requirement.
If desired, C
OUT
maybe increased without
limit to accommodate any load transient
Thermal Considerations
The YB1900 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
6
Reverse Output-to-Input Voltage
Conditions and Protection
YB1900 MRev.1.2
www.yobon.com.tw
YOBON [ YOBON TECHNOLOGIES,INC. ]
