YB1253 Datasheet, PDF (8/11 Pages) YOBON TECHNOLOGIES,INC. – 300mA, Low Power, High PSRR LDO Regulator

YB1253
300mA, Low Power, High PSRR LDO Regulator
Internal P-Channel Pass Transistor
The YB1253 features a low impedance P-channel
MOSFET pass transistor. This provides several
advantages over similar designs using a PNP pass
transistor, including low operating power and longer
battery life. The YB1253 consumes only 10µA of
quiescent current under most conditions.
Output Short-Circuit Current Limit
The YB1253 includes a current limiter, which
monitors and controls the pass transistor’s gate
voltage, limiting the output current to about 500mA,
for example, in a short-circuit output situation.
Shutdown
The YB1253 also features a low-power active
shutdown mode. It has a switch that turns off the
device when disabled. This allows the output
capacitor and load to discharge and de-energize the
load. In the shutdown mode, the internal functional
blocks, such as voltage reference and the error
amplifier are turned off completely, and the
quiescent current is less than 1µA.
Thermal Protection Shutdown
The thermal protection shutdown function protects
the device from operating in over temperature
condition. When the junction temperature exceeds
+160°C, the thermal sensor signals the shutdown
logic, turning off the pass transistor and allowing the
IC to cool down. The thermal sensor turns the pass
transistor on again after the IC’s junction
temperature drops to +140°C.
Application Information
Enable/Shutdown
The YB1253 comes with an active-high enable pin
that allows the regulator to be enabled. Forcing the
enable pin low disables the regulator and puts it into
the shutdown mode. This pin cannot be left floating
as it may cause an undetermined state.
Input/Output Capacitor
It is recommended to use a 1.0µF capacitor in the
YB1253 input and a 1.0µF capacitor in the output.
For high regulation performance, larger input
capacitor values and lower ESRs provide better
noise rejection and line-transient response. The
output noise, load-transient response, stability, and
power-supply rejection can be improved by using
large output capacitors. Low ESR ceramic
capacitors provide optimal performance and save
space.
YB1253 Rev. 1.5
www.yobon.com.tw
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