Fast transient response circuit applied to LDO

Abstract

The invention provides a fast transient response circuit applied to an LDO (low-dropout linear voltage stabilizer). An LDO circuit without out-of-chip bulk capacitor is adopted, the fast transient response capacity of the LDO can be enhanced by improving an internal circuit of the LDO, and other performances of the circuit cannot be weakened. The tail current of EA is divided into two parts: one part adopts fixed current bias, and the other part adopts the current from output load sampling; the static current of a chip cannot be increased in the circuit, and the response speed of the loop is also increased along with the increase of the bandwidth and the slew rate of the loop when the load is suddenly increased.

Description

technical field [0001] The invention relates to the field of integrated circuits, in particular to an LDO circuit. Background technique [0002] With the rapid development of integrated circuit technology, more and more related electronic products are used in daily life, and the performance requirements for related integrated circuit chips are also becoming higher. Low-dropout linear regulators (LDOs) are widely used in integrated circuits, especially low-power circuits, due to a series of characteristics such as low dropout voltage, low noise, and low power consumption. [0003] Although LDO has many advantages in related circuit design at this stage, the problem of transient response has always been a difficult problem in related design fields. When the LDO chip works under normal voltage, the current of the external load often changes. If the LDO circuit does not respond to the load transient in time, the output voltage of the LDO circuit will fluctuate greatly, which wi...

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Problems solved by technology

[0003] Although LDO has many advantages in related circuit design at this stage, the problem of transient response has always been a difficult problem in related design fields.

When the LDO chip works under normal voltage, the current of the external load often changes. If the LDO circuit does not respond to the load transient in time, the output voltage of the LDO circuit will fluctuate greatly, which will affect the normal operation of the chip.

At present, the circuit generally adopts the method of externally connecting a large off-chip capacitor to improve the transient response of the output end of the circuit, but because the off-chip capacitor can only be soldered to the outside of the chip, the integration of the chip is reduced, and the parasitic circuit generated on the circuit is increased. , seriously affect the stability of the circuit

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