The LDO circuit also includes a second pass transistor coupled to the control circuit and configured to provide a second pass current as a function of load current according to a second continuous conduction curve.Joseph Alan SANKMANRaveesh MAGOD RAMAKRISHNA...
图1是本文设计的LDO的基本结构框图,主要包括带隙基准电路(Bandgap)、误差放大器(EA)、调整管(Pass Transistor)以及反馈电阻(R1、R2)。其中带隙基准电路为误差放大器提供低温漂、高精准的参考电压Vref,误差放大器将输出反馈电压与参考电压进行比较,并放大其差值来控制调整管的导通状态,从而得到稳定的输出电压。输出电压...
a first pass transistor coupled to the control circuit and configured to provide a first pass current as a function of load current according to a first continuous conduction curve; and a second pass transistor coupled to the control circuit and configured to provide a second pass current as a...
the gain of the PMOS pass element decreases as it leaves saturation and enters the triode region. This causes the overall loop gain to decrease, resulting in lower PSRR. The smaller the headroom voltage, the more dramatic the reduction in gain. As the headroom voltage continues to decrease, i...
Figure 5.2 shows an LDO with a P-channel MOS pass transistor. The gate-source voltage of the LDO can be up to VIN. Since the LDO can operate in the linear region shown in Figure 5.3, the relationship between the input and output voltages can be expressed by Equation 5-2. Figure 5.2 ...
The current through a second pass transistor, being in parallel to a first pass transistor and being a fraction of the current through the first pass transistor is measured and compared with a reference current. In case the current through the second pass transistor is larger than this reference...
According to an aspect, a low dropout (LDO) voltage regulator includes a differential amplifier, a pass transistor coupled to an output of the differential amplifier, where the pass
Copper Area (WDFN6) www.onsemi.com 18 NCP705 Reverse Current The PMOS pass transistor has an inherent body diode which will be forward biased in the case that VOUT > VIN. Due to this fact in cases, where the extended reverse current condition can be anticipated the device may require ...
An LDO consists of a reference voltage, error amplifier, and a power-pass element, such as a MOSFET or bipolar transistor. The error amplifier provides dc gain to regulate the output voltage. The ac gain of the error amplifier in large part determines the PSRR. A typical LDO can have as...
The output voltage is regulated by a PNP pass transistor controlled by an error amplifier and band gap reference. The choice of a PNP pass element provides the lowest possible dropout voltage, particularly at reduced load currents. Pass transistor base drive current is controlled to prevent ...