l5953 STMicroelectronics, l5953 Datasheet - Page 15

• Manufacturer Part Number: l5953
• Description: Multiple Switching Voltage Regulator
• Manufacturer: STMicroelectronics

L5953
2.6
2.6.1
PWM step down voltage regulator
The switching regulator
as a direct duty cycle) Buck regulator: the error signal coming from the error amplifier is
compared with a sawtooth to set on and off times of the power switch.
The feedforward control is introduced to get a quickly response to input voltage changes: the
sawtooth has a fixed frequency and an amplitude variable with the battery voltage.
Continuous mode operation is recommended in order to reduce the stress of the output
capacitor and of the free-wheeling diode.
Error amplifier and compensation network
The error amplifier (EA) is a voltage amplifier whose non-inverting input is fixed to the
reference voltage (1.275V bandgap voltage) and whose inverting input and output are
externally available for feedback and frequency compensation.
(Figure
11.) inside the L5953 is a voltage control mode (also known
Functional description
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