The component you referred to, LP2985A-33DBVR, is a low-dropout regulator (LDO) manufactured by Texas Instruments. This part is used for voltage regulation, typically offering a stable 3.3V output for various low-power devices. The LP2985A-33DBVR comes in a SOT-23-5 package, which includes 5 pins.
Pin Function Specifications for LP2985A-33DBVR:
Package Type: SOT-23-5 Pin Count: 5 Pins
Pin Number Pin Name Pin Function Description Pin 1 IN This is the input pin for the LDO regulator. It should be connected to the input voltage source, which needs to be higher than the regulated output voltage. Pin 2 GND This is the ground pin of the LDO regulator. It should be connected to the system ground to provide a reference for the output voltage. Pin 3 OUT This is the output pin of the LDO regulator. It provides the regulated output voltage of 3.3V in the case of the LP2985A-33DBVR. Pin 4 FB The feedback pin. It is used to set the output voltage. In this case, for a 3.3V output, this pin will be connected to a feedback network (voltage divider) that ensures the correct output. Pin 5 ON/OFF This is the enable pin. When it is high, the regulator is enabled and provides the output voltage. If it is low, the regulator is disabled, and the output voltage will be zero.Circuit Principle:
The LP2985A-33DBVR works by regulating an input voltage down to a stable output voltage, which is set by the feedback pin (FB). It uses an internal pass element and feedback loop to achieve low dropout voltage (hence "LDO"). This is critical when the input voltage is close to the output voltage, allowing for efficient power conversion with minimal heat generation.
When designing a circuit using this component:
The IN pin must receive a voltage higher than 3.3V (typically between 4V and 6V). The OUT pin will output 3.3V. The FB pin is used to set the output voltage based on an external resistor network. The ON/OFF pin can be tied to a microcontroller or a manual switch to control the regulator’s operation. The GND pin should be connected to the system ground for proper functioning.FAQs for LP2985A-33DBVR:
What is the input voltage range for LP2985A-33DBVR? The input voltage range for the LP2985A-33DBVR is typically between 4V and 6V. What is the output voltage of LP2985A-33DBVR? The LP2985A-33DBVR provides a stable output voltage of 3.3V. How do I calculate the output voltage of the LP2985A-33DBVR? The output voltage is fixed at 3.3V in the LP2985A-33DBVR, and it cannot be adjusted. How many pins does the LP2985A-33DBVR have? The LP2985A-33DBVR has 5 pins in total. What type of package is LP2985A-33DBVR available in? The LP2985A-33DBVR is available in the SOT-23-5 package. What is the function of the ON/OFF pin in LP2985A-33DBVR? The ON/OFF pin is used to enable or disable the regulator. When high, the regulator is on; when low, the regulator is off. What is the dropout voltage for LP2985A-33DBVR? The dropout voltage of the LP2985A-33DBVR is typically around 40mV to 100mV depending on the load current. Can I use LP2985A-33DBVR in place of any 3.3V LDO? No, make sure the input voltage is within the range of 4V to 6V, and the required output current does not exceed the specifications of LP2985A-33DBVR. What is the maximum output current of LP2985A-33DBVR? The maximum output current is typically 150mA for the LP2985A-33DBVR.Can the LP2985A-33DBVR work with higher voltages?
No, the output voltage is fixed at 3.3V, and the input voltage must be higher than 3.3V.What is the typical quiescent current of LP2985A-33DBVR?
The quiescent current is typically around 30μA to 60μA, making it suitable for low-power applications.What type of capacitor s should I use with LP2985A-33DBVR?
A low ESR (equivalent series resistance) ceramic capacitor is recommended for both the input and output. Typical values are 10μF for input and 10μF for output.Is the LP2985A-33DBVR internally protected against overcurrent?
Yes, the LP2985A-33DBVR includes internal thermal shutdown and current limiting for protection.Can I connect the feedback pin (FB) directly to the output?
The FB pin is typically connected to a voltage divider to ensure proper output regulation, but in fixed-output versions like this, it is internally tied to the correct voltage.What happens if I leave the ON/OFF pin unconnected?
If the ON/OFF pin is left unconnected, the regulator will be enabled by default, and it will provide a stable output voltage.What is the maximum input voltage for LP2985A-33DBVR?
The maximum input voltage for the LP2985A-33DBVR is 6V.Can I use LP2985A-33DBVR to supply 5V to my circuit?
No, the LP2985A-33DBVR is specifically designed to provide 3.3V output.How stable is the output voltage under varying loads?
The LP2985A-33DBVR provides stable output voltage under varying loads, with minimal voltage drop or ripple.What are the thermal limitations of LP2985A-33DBVR?
The device has a thermal shutdown feature, and its junction temperature should not exceed 125°C.Can the LP2985A-33DBVR be used for high-power applications?
The LP2985A-33DBVR is not intended for high-power applications, as it is rated for low current (up to 150mA). For higher current, you would need a different LDO or a switching regulator.If you need more specific design guidance or additional FAQs, feel free to ask!