TPS79401DCQ

Due to market price fluctuations,if you need to purchase or consult the price.You can contact us or emial to us:   sales@allicdata.com

1. Describe

TPS79401DCQ series low dropout (LDO) linear Voltage stabilizer with high power supply Rejection ratio (PSRR), ultra-low noise, fast start, And excellent line and load transient response Small form factor, MSOP-8 PowerPAD™ and SOT223-6 Bag. Every device in the family has a stable Small 2.2µF ceramic capacitor on the output. this Series uses advanced proprietary BiCMOS Manufacturing process that produces extremely low pressure drop Voltage (for example, 155 mV at 250 mA). Each Fast start-up time of the device (approximately 50 µs (using 0.001 µF bypass capacitor), while Consumes low quiescent current (typically 170 µA). In addition, when the device is in standby Mode, the power supply current is reduced to less than 1 µA. TPS79428 shows approximately The output voltage noise of 32 µVRMS has a 2.8 V output A 0.1µF bypass capacitor. Simulation application Components sensitive to noise, such as Portable radio frequency electronic equipment that benefits from high PSRR And low noise function and fast response time.

2. Feature

    1. 250mA low-dropout regulator with enable function

    2. Available in fixed and adjustable (1.2 V to 5.5 V) versions

    3. High PSRR (60 dB at 10 kHz)

    4. Ultra-low noise (32 µVrms, TPS79428)

    5. Fast start-up time (50 µs)

    6. Stable when using 2.2µF ceramic capacitors

    7. Excellent load/line transient response

    8. Very low dropout voltage (155 mV at full load)

    9. Available in MSOP-8 and SOT223-6 packages

3. Pin configuration

4. Application

    1. RF: VCO, receiver, ADC

    2. Acoustic

    3. Bluetooth™, wireless LAN

    4. Mobile phones and cordless phones

    5. Handheld manager, PDA

5. Application information

TPS79401DCQ series low dropout (LDO) The regulator has been optimized for Noise sensitive equipment. Features Very low dropout, high PSRR, ultra low Output noise, low quiescent current (typically 265 µA), and enable input, reduce the supply current to less than 1 µA when the regulator is off.

6. External capacitor requirements

A ceramic input bypass capacitor of 1µF or greater, Connect between IN and GND and close To TPS794xx, for stability and Improve transient response, noise suppression and Ripple suppression. Higher value input capacitors may If large, fast rise time load transients are necessary It is expected that the device is located in multiple A few inches from the power source. Like most low-dropout regulators, TPS794xx Requires an output capacitor to be connected to OUT and GND are used to stabilize the internal control loop. The minimum recommended capacitance is 1 µF. Any ceramic capacitor of 1 µF or larger is suitable. The internal reference voltage source is Noise in the LDO regulator. TPS794xx has Connect to the NR pin of the reference voltage Through an internal resistance of 250kΩ. 250kΩ Internal resistance, combined with external Bypass capacitor connected to the NR pin to create a Low-pass filter to reduce reference voltage noise Therefore, noise at the output of the regulator. exist In order to make the regulator operate normally, The current flowing from the NR pin must be minimal, Because any leakage current will cause IR drop Across the internal resistance to produce an output mistake. Therefore, the bypass capacitor must have Minimum leakage current.

7. REGULATOR PROTECTION

The TPS79401DCQ PMOS-pass transistor has a built-in back diode that conducts reverse current when the input voltage drops below the output voltage (for example, during power down). Current is conducted from the output to the input and is not internally limited. If extended reverse voltage operation is anticipated, external limiting might be appropriate. The TPS794xx features internal current limiting and thermal protection. During normal operation, the TPS794xx limits output current to approximately 2.8 A. When current limiting engages, the output voltage scales back linearly until the overcurrent condition ends. While current limiting is designed to prevent gross device failure, care should be taken not to exceed the power dissipation ratings of the package. If the temperature of the device exceeds approximately 165°C, thermal-protection circuitry shuts it down. Once the device has cooled down to below approximately 140°C, regulator operation resumes.