中文
English供应50mA的超低静态电流LDO线性稳压器AP8841,深圳上海北京现货特价出售
Features
Operating Voltages Range：+2.5V to +18.0V
Output Voltages Range：+1.5V to +5.0V with 100mV Increment
Low Dropout: 800mV @ 50mA
High Output Voltage Accuracy
±2%：VOUT≧2.7V
±2.4%：VOUT≦2.6V
Thermal Overload Shutdown Protection
Low ESR Capacitor Compatible
SOT-23, SOT-89 & TO-92 Packages
RoHS Compliant and 100% Lead (Pb)-Free and Green (Halogen Free with Commercial Standard)
Applications
Battery powered Equipments
Portable Communication Devices
Precision Voltage References
Hand-Held Electronics
Wireless Communication Systems
General Description
The AP8841 series is a positive voltage regulator with high accuracy
output voltage and ultra-low quiescent current which is typically 1.0μA.
The device is ideal for battery powered handheld equipments which
require low quiescent current.
The AP8841 contains a bandgap voltage
reference,an error amplifier, a P-channel pass transistor, and a
resistor-divider for setting output voltage. The output voltage is fixed
with high accuracy by advanced trimming technology.
The AP8841
has been designed to be used with low cost ceramic capacitors and
requires a minimum output capacitor of 1.0μF. The devices are available
in SOT-23, SOT-89, and TO-92 packages
Simplified Application Circuit
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Function Block Diagram
Current Boost Circuit
The figure below shows a boost circuit for increasing the output current. Output current 60mA or more can be obtained by this circuit.
Short-Circuit protection of Tr1 can be implemented by adding the sense resistor RS and the PNP transistor Tr2 as shown below.
The current limit of the protection circuit is:
Voltage Boost Circuit
If the output voltage you need is greater than 5.0V, the circuit in the figure below will increase output voltages easily
The output voltage is obtained by:
Where
VSET is the preset output voltage of AP8841 and ISS is the quiescent
current. Because of the low quiescent current, the resistor values, R1
and R2,can be set as large as several hundreds kΩ to lower the power
consumption of the whole
system.
Constant Current Source
The AP8841 Series can be used as a constant
current source within allowable current limit.
The output current is obtained by:
Dual Supply
A dual supply can be constructed with two AP8841 series as show in the
figure below. This circuit provides two outputs (5V and 8V) with the
AP8841 -30Px and the AP8841-50Px. As the resistance R lets the quiescent
current of IC1 pass. R is unnecessary if the minimum output current of
IC2 is more than the IC1 quiescent current. D is a protection diode in
case VOUT2 becomes larger than VOUT1.
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