Overview
The TPS7A85, produced by Texas Instruments, is a high-performance, low-noise, low-dropout linear regulator (LDO) designed to source up to 4 A of current with a maximum dropout voltage of 240 mV. This device is ideal for powering noise-sensitive components in various high-speed and precision applications. It features a pin-programmable output voltage range from 0.8 V to 3.95 V and an adjustable output voltage range from 0.8 V to 5.0 V using an external resistor divider. The TPS7A85 is known for its high accuracy, excellent load transient response, and high power-supply ripple rejection ratio (PSRR), making it suitable for applications in high-speed communications, video, medical, and test and measurement equipment.
Key Specifications
| Parameter | Minimum | Typical | Maximum | Unit |
|---|---|---|---|---|
| Input Supply Voltage Range (VIN) | 1.1 | - | 6.5 | V |
| Bias Supply Voltage Range (VBIAS) | 3.0 | - | 6.5 | V |
| Output Voltage Range (VOUT) | 0.8 | - | 5.0 | V |
| Output Current (IOUT) | 0 | - | 4 | A |
| Dropout Voltage | - | 150 mV (typ) at 4 A | 240 mV (max) at 4 A | mV |
| Output Voltage Noise (Vn) | - | 4.4 µVRMS at 0.8 V output | 8.4 µVRMS at 5.0 V output | µVRMS |
| Power-Supply Ripple Rejection (PSRR) | - | 40 dB at 500 kHz | - | dB |
| Operating Junction Temperature (TJ) | -40 | - | 125 | °C |
| Package Type | - | - | 3.5-mm × 3.5-mm, 20-Pin VQFN | - |
Key Features
- Low dropout voltage: 150 mV (typ) at 4 A, maximum 240 mV at 4 A.
- High accuracy: 1% (max) over line, load, and temperature.
- Low output noise: 4.4 µVRMS at 0.8 V output, 8.4 µVRMS at 5.0 V output.
- High power-supply ripple rejection ratio (PSRR): 40 dB at 500 kHz.
- Excellent load transient response.
- Adjustable soft-start in-rush control.
- Open-drain power-good (PG) output.
- Stable with a 47-µF or larger ceramic output capacitor.
- ANY-OUT™ operation: output voltage range from 0.8 V to 3.95 V.
- Adjustable operation: output voltage range from 0.8 V to 5.0 V using an external resistor divider.
Applications
- Digital loads: SerDes, FPGAs, DSPs, and ASICs.
- Instrumentation, medical, and audio equipment.
- High-speed analog circuits: VCO, ADC, DAC, LVDS.
- Imaging: CMOS sensors and video ASICs.
- Test and measurement equipment.
- RF components: RF amplifiers and other high-performance RF applications.
Q & A
- What is the maximum output current of the TPS7A85?
The TPS7A85 can source up to 4 A of output current.
- What is the typical dropout voltage of the TPS7A85 at 4 A?
The typical dropout voltage is 150 mV at 4 A.
- What is the output voltage noise of the TPS7A85 at 0.8 V output?
The output voltage noise is 4.4 µVRMS at 0.8 V output.
- What is the power-supply ripple rejection ratio (PSRR) of the TPS7A85 at 500 kHz?
The PSRR is 40 dB at 500 kHz.
- What is the operating junction temperature range of the TPS7A85?
The operating junction temperature range is from -40°C to +125°C.
- How is the output voltage of the TPS7A85 adjusted?
The output voltage can be adjusted from 0.8 V to 5.0 V using an external resistor divider.
- What type of package does the TPS7A85 come in?
The TPS7A85 comes in a 3.5-mm × 3.5-mm, 20-Pin VQFN package.
- What is the ANY-OUT™ operation feature of the TPS7A85?
The ANY-OUT™ operation allows the output voltage to be set from 0.8 V to 3.95 V without the need for external resistors.
- Does the TPS7A85 have a power-good (PG) output feature?
Yes, the TPS7A85 has an open-drain power-good (PG) output that indicates when the output voltage reaches 89.3% of the target voltage.
- What kind of capacitors are recommended for the output of the TPS7A85?
The TPS7A85 is stable with a 47-µF or larger ceramic output capacitor.
