Sharp LC-19LE510E, Service Manual

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LC-19LE510
LC-22LE510
LC-24LE510
20. MP1583 (U174)
20.1. General Description
The MP1583 is a step-down regulator with a built-in internal Power MOSFET. It achieves 3A of continuous
output current over a wide input supply range with excellent load and line regulation. Current mode
operation provides fast transient response and eases loop stabilization. Fault condition protection
includes cycle-by-cycle current limiting and thermal shutdown. An adjustable soft-start reduces the
stress on the input source at start-up. The MP1583 requires a minimum number of external components,
providing a compact solution.
20.2. Features

3A Output Current

Programmable Soft-Start
 100mΩ Internal Power MOSFET Switch

Stable with Low ESR Output Ceramic Capacitors
 Up to 95% Efficiency

20μA Shutdown Mode
 Fixed 385KHz Frequency

Thermal Shutdown
 Cycle-by-Cycle Over Current Protection

Wide 4.75V to 23V Operating Input Range
 Output Adjustable from 1.22V to 21V

Under-Voltage Lockout
20.3. Pinning
Pin
No.
Pin
Name
Description
1
BOOT High-Side Gate Drive Bootstrap Input. BS supplies the drive for the
high-side N-Channel MOSFET switch.
2
IN Power Input. Drive IN with a 4.75V to 23V power source.
3
SW Power Switching Out is the switching node that supplies power to the
output
4
GND Ground.
5 FB Feedback Input. FB senses the output voltage and regulates it. Drive
FB with a resistive voltage divider from the output voltage. FB
threshold is 1.222V.
6 COMP Compensation Node is used to compensate the regulation control
loop.
7
EN Enable/UVLO. A voltage greater than 2.71V enables operation. For
complete low current shutdown the EN pin voltage needs to be at less
than 900mV. When the voltage on EN exceeds 1.2V, the internal
regulator will be enabled and the soft-start capacitor will begin to
charge. The MP1583 will start switching after the EN pin voltage
reaches 2.71V.
8
SS Soft-Start Control Input. SS controls the soft-start period.
20. MP1583 (U174)
20.1. General Description
The MP1583 is a step-down regulator with a built-in internal Power MOSFET. It achieves 3A of continuous
output current over a wide input supply range with excellent load and line regulation. Current mode
operation provides fast transient response and eases loop stabilization. Fault condition protection
includes cycle-by-cycle current limiting and thermal shutdown. An adjustable soft-start reduces the
stress on the input source at start-up. The MP1583 requires a minimum number of external components,
providing a compact solution.
20.2. Features
 3A Output Current

Programmable Soft-Start

100mΩ Internal Power MOSFET Switch

Stable with Low ESR Output Ceramic Capacitors
 Up to 95% Efficiency

20μA Shutdown Mode

Fixed 385KHz Frequency
 Thermal Shutdown

Cycle-by-Cycle Over Current Protection

Wide 4.75V to 23V Operating Input Range
 Output Adjustable from 1.22V to 21V

Under-Voltage Lockout
20.3. Pinning
Pin
No.
Pin
Name
Description
1 BOOT High-Side Gate Drive Bootstrap Input. BS supplies the drive for the
high-side N-Channel MOSFET switch.
2
IN Power Input. Drive IN with a 4.75V to 23V power source.
3 SW Power Switching Out is the switching node that supplies power to the
output
4
GND Ground.
5
FB Feedback Input. FB senses the output voltage and regulates it. Drive
FB with a resistive voltage divider from the output voltage. FB
19.
19.3
19.2
19.1