ADP7118ARDZ-5.0 vs LM2941S
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| Category | PMIC - Voltage Regulators - Linear | PMIC - Voltage Regulators - Linear |
| Manufacturer | Analog Devices Inc. | Texas Instruments |
| Description | IC REG LINEAR 5V 200MA 8SOIC | IC REG LIN POS ADJ 1A DDPAK |
| Package | Cut Tape (CT) | Tape & Reel (TR) |
| Series | - | - |
| Operating Temperature | -40°C ~ 125°C (TA) | -40°C ~ 125°C |
| Mounting Type | Surface Mount | Surface Mount |
| Package / Case | 8-SOIC (0.154\", 3.90mm Width) Exposed Pad | TO-263-6, D²Pak (5 Leads + Tab), TO-263BA |
| Supplier Device Package | 8-SOIC-EP | DDPAK/TO-263-5 |
| Output Type | Fixed | Adjustable |
| Voltage - Output (Min/Fixed) | 5V | 5V |
| Voltage - Output (Max) | - | 20V |
| Current - Output | 200mA | 1A |
| Output Configuration | Positive | Positive |
| Control Features | Enable, Soft Start | Enable |
| Voltage - Input (Max) | 20V | 26V |
| Number of Regulators | 1 | 1 |
| Voltage Dropout (Max) | 0.42V @ 200mA | 1V @ 1A |
| Current - Quiescent (Iq) | 140 µA | 10 mA |
| Current - Supply (Max) | 320 µA | 15 mA |
| PSRR | 88dB ~ 50dB (10kHz ~ 1MHz) | - |
| Protection Features | Over Current, Over Temperature | Over Temperature, Reverse Polarity, Short Circuit |
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1. What are the disadvantages of linear regulators?
The disadvantage of linear regulators is that they are not efficient and can only be used in voltage reduction applications. The efficiency of a linear regulator depends on the ratio of output voltage to input voltage: turbidity = Vo: Vi. For example, for ordinary linear regulators, when the input voltage is 5V and the output voltage is 2.5V, the efficiency is only 50%. For ordinary linear regulators, about 50% of the electrical energy is converted into "heat" and lost, which is also the main reason why ordinary linear regulators are prone to heat when working. For LDO, due to its low voltage difference, the efficiency is much higher. For example, when the input voltage is 3.3V and the output voltage is 2.5V, its efficiency can reach 76%. Therefore, in LCD color TVs, in order to improve the utilization rate of electrical energy, ordinary linear regulators are used less, while LDOs are used more.
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2. What problems will linear regulators bring to the circuit?
The problems that linear regulators bring to the circuit mainly include low efficiency and a lot of heat.
Linear The main working principle of the voltage regulator is to control the output voltage of the transistor through a current amplifier to keep the output voltage stable. This working mode causes the linear regulator to control the regulating tube through a differential voltage when adjusting the output voltage. The control tube needs to absorb part of the input voltage, which makes the efficiency of the linear regulator relatively low. In practical applications, this means that the linear regulator will convert the difference between the input voltage and the output voltage into heat energy, causing serious heating of the device, especially when the input and output voltage difference is large, this power loss will further increase, causing the device to heat up. -
3. How to choose a linear regulator?
1. Switching regulator: A switching regulator uses an output stage that repeatedly switches between "on" and "off" states to generate an output voltage together with an energy storage component. Its adjustment is achieved by adjusting the switching timing based on the feedback sample of the output voltage. In a fixed-frequency regulator, the switching timing is adjusted by adjusting the pulse width of the switching voltage, which is called PWM control.
2. Parameter regulator: LDO is a linear regulator. Linear regulators use transistors or FETs operating in their linear region to subtract excess voltage from the applied input voltage to produce a regulated output voltage. This transistor allows saturation, so the regulator can have a very low dropout voltage, usually around 200mV.
3. Regulators for laser cutting machines: According to the use requirements of high-power laser cutting machines and the current power supply situation in my country, regulators that meet -
4. Can a linear regulator be up?
Linear regulators cannot be boost.
The main function of a linear regulator is to stabilize the output voltage, protecting the electrical equipment from high or unstable voltage effects. It realizes a stable output voltage by adjusting the gap between the output voltage and the input voltage, but this process is limited to lowering the voltage, not including the voltage. The working principle of a linear regulator is to regulate the voltage by converting excess voltage into heat loss, thereby realizing the voltage regulation. This feature determines that it does not have the voltage function.
