TPS7A3301 - 1A, -36V Ultra-Low Noise Negative LDO | Texas Instruments
MPN: TPS7A3301 β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $4.85 | $4.85 |
| 10 | $4.36 | $43.60 |
| 100 | $3.88 | $388.00 |
| 500 | $3.49 | $1,745.00 |
| 1,000 | $3.1 | $3,100.00 |
TPS7A3301 Overview
Key features include an output noise of 12.7 uVrms (20 Hz to 100 kHz), a power supply rejection ratio (PSRR) of 75 dB at 1 kHz, and a low dropout voltage of 300 mV at full 1A load. The device also offers an active-low enable pin for power sequencing, a programmable soft-start function to limit inrush current, and thermal shutdown protection. The VQFN-20 package provides a thermal resistance of 31.4 C/W, allowing moderate power dissipation without external heatsinking.
The TPS7A3301 employs a precision bandgap reference and a low-noise architecture, achieving noise performance comparable to discrete reference designs while maintaining regulator simplicity. The high PSRR minimizes ripple from upstream switching converters, making it ideal for noise-sensitive analog and RF signal chains where clean negative power rails are critical.
Typical applications include audio DAC and op-amp negative supplies, RF transceiver bias circuits, precision ADC/DAC reference buffering, and test and measurement instrumentation. The wide input range also supports industrial -24V bus systems with adequate headroom.
When designing with this device, ensure adequate input-to-output voltage headroom to maintain regulation under all load conditions. The enable pin allows sequential power-up in multi-rail systems, which is essential for processors requiring specific rail sequencing. Proper PCB layout with adequate copper pour is recommended for thermal management.
Drop-in alternatives for TPS7A3301 β same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Quick Comparison Tool β Select alternative parts for side-by-side comparison:
TPS7A4701RGWR
β In Stock
$3.2467 / Unit
View Datasheet βLT3094
β In Stock
$4 / Unit
View Datasheet βADP7182
π Reference alternative (not in catalog)
LT3015
π Reference alternative (not in catalog)
TPS7A3301 Maximum Ratings & Electrical Characteristics
| Output Type | Adjustable |
| Output Voltage Range | -1.18 V to -33 V |
| Maximum Output Current | 1 A |
| Input Voltage Range | -3 V to -36 V |
| Dropout Voltage | 300 mV at 1 A |
| Output Noise | 12.7 uVrms (20 Hz to 100 kHz) |
| PSRR | 75 dB at 1 kHz |
| Quiescent Current | 6.4 mA |
| Thermal Resistance | 31.4 C/W |
| Operating Temperature | -40C to +125C |
| Package | VQFN-20 (RGW) 5x5 mm |
| Mounting Type | Surface Mount |
| MSL Level | 2 (1 year) |
| RoHS Status | Compliant |
| Enable Pin | Yes (active-low) |
TPS7A3301 Pin Configuration
| Pin 1 | OUT β Regulated negative output voltage |
| Pin 5 | GND β Ground |
| Pin 6 | EN β Enable (active low) |
| Pin 7 | IN β Negative input supply |
Typical Applications
TPS7A3301 is suitable for 6 applications: High-End Audio DAC Negative Supply, RF Transceiver Bias, Precision ADC/DAC Reference, Industrial -24V Bus Systems, Test and Measurement Instrumentation, Medical Monitoring Equipment.
High-End Audio DAC Negative Supply
Provides clean -5V rail for audio DACs with 12.7uVrms noise.
Recommended
RF Transceiver Bias
Provides low-noise negative bias for RF amplifiers and mixers.
Recommended
Precision ADC/DAC Reference
Buffers negative reference voltages for precision converters.
Recommended
Industrial -24V Bus Systems
Regulates -24V industrial buses to lower voltages for control circuits.
Recommended
Test and Measurement Instrumentation
Provides clean negative rails for precision measurement circuits.
Recommended
Medical Monitoring Equipment
Supplies low-noise negative rails for sensitive medical sensors.
Recommended
Recommended Products Summary
Engineering reference data for TPS7A3301 β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LT3094 | ADP7182 | LT3015 |
|---|---|---|---|---|
| Output Current | 1 A | 0.2 A | 0.2 A | 1.5 A |
| Output Noise | 12.7 uVrms | 0.8 uVrms | 1.0 uVrms | 6.8 uVrms |
| PSRR at 1kHz | 75 dB | 79 dB | 65 dB | 40 dB |
| Input Voltage Range | -3 V to -36 V | -2.2 V to -20 V | -2.7 V to -28 V | -1.9 V to -30 V |
| Dropout Voltage | 300 mV at 1 A | 300 mV at 0.2 A | 200 mV at 0.2 A | 300 mV at 1.5 A |
| Enable Pin | Yes (active-low) | Yes (active-low) | Yes (active-low) | Yes (active-low) |
| Package | VQFN-20 | DFN-12 | LFCSP-8 | DDPAK-5 |
| Price (1pc) | 4.85 USD | 5.50 USD | 3.20 USD | 4.10 USD |
Key Differentiators
- Highest output current in ultra-low-noise negative LDO class (vs LT3094)
- Widest input voltage range (vs ADP7182)
- Best PSRR at 1kHz (vs LT3015)
Design Notes
At VIN=-12V, VOUT=-5V, and 1A load, power dissipation is 7W. The VQFN-20 package has theta_JA of 31.4 C/W, resulting in a 220C junction temperature rise. A heatsink or at least 1 square inch of copper pour is required for reliable operation above 2W dissipation.
Place input and output capacitors as close to the IC pins as possible. Use a 10uF ceramic capacitor on the input and a 10uF ceramic capacitor on the output. Add a 0.1uF ceramic capacitor in parallel for high-frequency noise bypass.
Do not exceed the maximum input voltage of -36V. Ensure the external resistor divider uses 1% or better tolerance resistors to maintain output voltage accuracy. The NR/SS capacitor controls startup time and noise bandwidth - do not omit it.
Compliance Information
RoHS compliant per TI product page. Not AEC-Q100 qualified - not intended for automotive safety applications.