Voltage regulators are one of the core Power Management ICs (PMICs) used with many consumer electronics. These regulators work by enabling a real-time regulation of the power or current transmission to and from the target applications.
Now, there are different variants of these regulators and the linear voltage regulators are one of such. In this article, we discuss TPS76801MPWPREP as a linear voltage regulator with a fast transient response capability.
What is a Linear Voltage Regulator?
Generally, voltage regulators help in optimizing how current (power) is to be received and converted to the best performances.
But what is a linear voltage regulator and why does it matter in the scheme of things? Linear voltage regulator is a type of voltage regulator that maintains a fixed output voltage. This maintenance is done by using a controlling circuit to regulate the driver transistor’s resistance.
Wikipedia adds that one of the core features of a linear voltage regulator is the heat dissipation model, which involves dissipating heat across the regulation device. Doing this helps the linear voltage regulator to effectively control the target device’s output voltage.
TPS76801MPWPREP is a Low-Dropout Voltage: What Does It Do?
Further breaking it down, TPS76801MPWPREP works as a Low-Dropout Voltage or LDO. According to Texas Instruments, an LDO is a type of voltage that provides a “regulated output voltage that is powered from a higher voltage input.” This is implementable in a variety of applications.
Wikipedia furthers add that a Low-Dropout Voltage (LDO) is a type of Direct Current (DC) linear voltage regulator, capable of regulating the output voltage. The regulation is done, irrespective of whether the supply voltage is closer to the output voltage or not.
The Power Good Feature
Besides regulating the output voltage, the TPS76801MPWPREP’s LDO also helps optimize the regulator for the best power uses. It does this with the Power Good (PG) feature. The feature helps to implement either a low-battery indictor or a power-on reset for the target device.
It has a Controlled Baseline
The controlled baseline used here refers to the one-housed design for how TPS76801MPWPREP operates. Here, we have the likes of one fabrication site and one assembly and test site.
Therefore, everything relating to how TPS76801MPWPREP is to be configured for the best possible results and performances are processed here.
TPS76801MPWPREP’s Response to the pnp Pass Element
The pnp Pass Element is a common feature on most Low-Dropout Voltage Regulators (LDOs). The pnp Pass Element is a “base current” proportional to the load current passed through the regulator.
However, there are a couple of design challenges peculiar to the pnp Pass Element. These challenges include:
1. Low-Operating Current
The system’s operating current is usually low and can sometimes, be invariably over the full load range. That happens when the system’s pnp Pass Element uses a PMOS Transistor to pass current, rather than using the PMOS gate. The latter (the PMOS gate) could have been used, but wouldn’t because the gate is driven by the voltage.
2. Large Start-Up Currents
The start-up currents are usually higher on devices designed with the pnp Pass Element. It happens because of the following factors:
- The pnp Pass Element tends to saturate when the device goes into dropout.
- There is a drop in the ß forces. This drop paves the way for an increase in the IB required to maintain the load.
It is therefore, imperative to find a viable way to address that concern. TPS76801MPWPREP perfectly handles that via the very low quiescent current. The amazing thing about this current is that it remains “virtually constant even when with varying loads.”
TPS76801MPWPREP is Stable
TPS76801MPWPREP is designed to be a stable Linear Voltage Regulator, as it is designed to have a fast transient response that makes the system stable when working with the 10-µF low ESR capacitors.
What You Need to Know about a Low-Dropout (LDO) Voltage
We have ascertained that TPS76801MPWPREP is a Low-Dropout (LDO) voltage and that it can help balance the current transfer within the system.
Now, let us look at some of the additional pieces of information that are sometimes left out about how an LDO works:
3. Power Conversion to Heat
It is the number one function of a Low-Dropout Voltage (LDO) voltage to convert excess power into heat. This conversion is first, a good way to regulate the voltage and a process for making the TPS76801MPWPREP Integrated Circuit (IC) ideal for use with the small-sized and low-power applications.
4. An LDO can Tackle Noise
Noisy operation is tenable in some circuits and it is in the place of the Low-Dropout (LDO) voltage to limit that.
Depending on the design process, it may be worth it to use a High-Power-Supply Rejection Ratio (PSRR) regulator. It works by operating at a higher bandwidth, which paves the way for the LDO to “close the gap in noise” by filter the switching noise coming from the upstream DC-to-DC converters.
Choosing and LDO: What to Look for
Naturally, your choice of a Low-Dropout (LDO) voltage that doubles as a linear voltage regulator is along the lines of “how much does it cost.”
While cost is an important consideration, it doesn’t always have to come first-place over other important factors. If you are looking to buy an LDO like TPS76801MPWPREP, these are a few of the things to look for:
5. Power Dissipation Process
How does the LDO handle excessive power? In TPS76801MPWPREP’s case, it does that by spreading or dissipating the excessive power through the conversion into heat.
6. Load Current
How many loads can the LDO carry or support? Pay attention to both the minimum and the maximum load current.
The major thing to consider in this case is the functioning of the LDO after loading. For TPS76801MPWPREP, it remains “virtually constant even with varying loads.” It also remains stable even at zero load; making it one of the LDOs that function effectively without needing any minimum load for the operation.
Conclusion
TPS76801MPWPREP’s fast transient response is a unique feature that helps the Low-Dropout (LDO) voltage to maintain a regulated output voltage as a response to the sudden changes in the load current.
