Texas Instruments Claims its New Low-dropout (LDO) Regulator Features Industry-low Noise Level

Introduced at the Applied Power Electronics Conference 2022 (APEC 2022), Texas Instruments’ TPS7A94 LDO linear regulator is aimed at assisting power designers in minimizing EMI and noise, as well as improving power density and reliability. 

 

TI’s TPS7A94 generates exceptionally low output noise over the entire frequency spectrum. Image used courtesy of TI

 

The TPS7A94 features output noise of only 0.46 µVRMS, measured over a frequency range of 10 Hz to 100 kHz, a mark that TI claims is at least 42% better than competing solutions. Complete with exceptionally high power-supply rejection ratios, the LDO could be a boon to designers seeking to improve system accuracy and precision in highly sensitive applications such as medical equipment, wireless infrastructure and radar. 

 

Principal Features

The TPS7A94 features a maximum dropout voltage of 200 mV at the device’s 1 A maximum output. It accepts input voltages ranging from 1.7 to 5.7 V, and sports output voltages of 0.4 to 5.5 V.

Power supply ripple rejections (PSSR) are specified at:

• 70 dB at DC
• 100 dB at 1 kHz
• 90 dB at 10 kHz
• 70 dB at 100 kHz
• 60 dB at 1 MHz 

Units can be paralleled for higher current requirements. Undervoltage lockout (UVLO) is resistor-programmable, as is the power good (PG) threshold and the current limit. The unit’s start-up inrush current is also adjustable. 

 

A typical application circuit for the TPS7A94. Image used courtesy of TI

 

The LDO features 1% output accuracy over line, load, and temperature variation. In addition, it sports a thermal pad electrically connected to ground, which itself is mounted to the ground plane, providing enhanced thermal performance.

 

Other Electrical Specifications

Ground pin current:

• 15 mA (typ) @Vin = 5.5 V, Iout = 0.1 mA 
• 41 mA (typ) @Vin = 1.7 V, Iout = 1 A, Vout = 1.2 V 

Thermal resistance, JEDEC Standard (2s2p):

• Junction-to-ambient thermal resistance, RθJA: 46.1°C/W 
• Junction-to-board thermal resistance, RθJB: 19.1°C/W 
• Junction-to-case (top) thermal resistance, RθJC (top): 35.2°C/W
• Junction-to-case (bottom) thermal resistance, RθJC (bot): 3.9°C/W

 

Applications

• Macro remote radio units (RRU)
• Outdoor backhaul units
• Active antenna system mMIMO (AAS)
• Ultrasound scanners
• Lab and field instrumentation
• Sensor, imaging, and radar
• Voltage-controlled oscillators (VCOs)
• Analog-to digital converters (ADCs)
• Digital-to-analog converters (DACs)
• High-end processors
• Field-programmable gate arrays (FPGAs)

 

Physical Considerations

• The TPS7A94 is available in a 3 x 3 x 0.8 mm 10-pin WSON package
• The LDO operates over a -55 to 125 °C temperature range

 

Getting to Market Faster

To make it easier for designers to more quickly evaluate and utilize the TPS7A94, TI provides an evaluation module (EVM), the TPS7A94EVM-046. 

 

The TPS7A94EVM-046. Image used courtesy of TI 

 

It is available with a comprehensive user's guide, including instructions for setup and operation, thermal guidelines, schematics, and more. 

 

Feature image [modified] used courtesy of TI