LD39030DTPU33R - 3.3V 300mA Ultra-Low Noise LDO | STMicroelectronics
MPN: LD39030DTPU33R β Active| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $0.45 | $0.45 |
| 10 | $0.38 | $3.80 |
| 100 | $0.3 | $30.00 |
| 500 | $0.25 | $125.00 |
| 1,000 | $0.2 | $200.00 |
Drop-in alternatives for LD39030DTPU33R 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:
LD39030DTPU33R-Q1
β Drop-Inπ Reference alternative (not in catalog)
LD39030DTPU28R
β Drop-Inπ Reference alternative (not in catalog)
LD39030DTPU18R
β Drop-Inπ Reference alternative (not in catalog)
TPS7A2033PDSNR
β Drop-Inπ Reference alternative (not in catalog)
NCP700B33T2G
β‘ Same Packageπ Reference alternative (not in catalog)
LD39030DTPU33R Maximum Ratings & Electrical Characteristics
| Output Type | Fixed |
| Output Voltage | 3.3 V |
| Maximum Output Current | 300 mA |
| Input Voltage Range | 1.5 V to 5.5 V |
| Dropout Voltage | 120 mV at 300 mA |
| Output Noise | 10 uVrms (10 Hz to 100 kHz) |
| PSRR | 70 dB at 1 kHz |
| Quiescent Current | 40 uA |
| Line Regulation | 0.01 %/V |
| Load Regulation | 0.01 %/mA |
| Thermal Resistance | 90 C/W |
| Operating Temperature | -40C to +125C |
| Package | UDFN-6 (2x2 mm) |
| Mounting Type | Surface Mount |
| MSL Level | 1 (unlimited) |
| RoHS Status | Compliant |
| Enable Pin | Yes (active-high) |
LD39030DTPU33R Pin Configuration
| Pin 1 | IN β Input supply voltage |
| Pin 2 | GND β Ground |
| Pin 3 | EN β Enable (active high) |
| Pin 4 | NC β No connect |
| Pin 5 | OUT β Regulated output voltage |
| Pin 6 | NC β No connect |
Safe Operating Area (SOA) & Thermal Characteristics
No official SOA curve available for this component. Always operate within absolute maximum ratings specified in the datasheet. Ensure adequate cooling and derate as needed.
Typical Applications
LD39030DTPU33R is suitable for 6 applications: Audio Codec Power Supply, RF Transceiver Power Rail, Portable Medical Devices, IoT Sensor Nodes, Battery-Powered Wearables, Industrial Sensor Interfaces.
Audio Codec Power Supply
The LD39030DTPU33R provides a clean 3.3V rail for audio codecs, with 10 uVrms noise and 70 dB PSRR ensuring minimal audio interference. In a typical audio codec application, the LDO is placed between the system 5V rail and the codec's AVDD pin, with a 1uF ceramic capacitor on input and output. The low noise floor preserves the dynamic range of the audio signal, while the high PSRR rejects ripple from switching regulators. Compared to switching regulators, the LDO eliminates switching noise but dissipates more power; for a 5V-to-3.3V conversion at 100mA, power dissipation is 170mW, which is acceptable for most portable devices.
Recommended
RF Transceiver Power Rail
The LD39030DTPU33R is ideal for powering RF transceivers, where noise on the supply can degrade signal integrity. Its 10 uVrms noise and 70 dB PSRR at 1 kHz ensure a clean power rail for VCOs and PLLs. In a typical RF application, the LDO is placed close to the transceiver's power pin, with a 0.1uF capacitor for high-frequency bypass. The low quiescent current of 40 uA extends battery life in portable RF devices. The enable pin allows the RF section to be powered down during standby, reducing overall power consumption.
Recommended
Portable Medical Devices
The LD39030DTPU33R is suitable for portable medical devices such as glucose monitors and pulse oximeters, where low power and low noise are critical. The 40 uA quiescent current extends battery life, while the 10 uVrms noise ensures accurate sensor readings. In a typical medical device, the LDO regulates the battery voltage to 3.3V for the microcontroller and sensor interface. The small UDFN-6 package saves board space, and the wide operating temperature range (-40C to +125C) ensures reliable operation in various environments.
Recommended
IoT Sensor Nodes
The LD39030DTPU33R is well-suited for IoT sensor nodes that require a stable 3.3V supply from a battery or energy harvester. The low dropout voltage of 120 mV allows operation from a nearly discharged battery, maximizing usable capacity. The enable pin enables duty-cycling to reduce average power consumption. In a typical IoT node, the LDO powers a microcontroller, sensor, and wireless module. The low quiescent current is essential for long battery life, and the compact package fits into small form factors.
Recommended
Battery-Powered Wearables
The LD39030DTPU33R is ideal for wearables like smartwatches and fitness trackers, where space and power are at a premium. The UDFN-6 package (2x2 mm) is one of the smallest available for a 300mA LDO, and the 40 uA quiescent current extends battery life. The low dropout voltage ensures efficient operation from a Li-ion battery. In a typical wearable, the LDO provides a clean 3.3V rail for the application processor and sensors. The enable pin allows power gating of peripheral blocks to save energy.
Recommended
Industrial Sensor Interfaces
The LD39030DTPU33R can be used in industrial sensor interfaces that require a stable 3.3V supply for analog-to-digital converters and signal conditioning circuits. The high PSRR of 70 dB at 1 kHz rejects noise from industrial power lines, ensuring accurate measurements. The wide operating temperature range (-40C to +125C) makes it suitable for harsh environments. In a typical industrial sensor interface, the LDO powers the ADC and op-amps, providing a clean reference rail. The low noise performance is critical for high-resolution measurements.
Recommended
Recommended Products Summary
Engineering reference data for LD39030DTPU33R β comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | LD39030DTPU33R-Q1 | LD39030DTPU28R | TPS7A2033PDSNR |
|---|---|---|---|---|
| Package | UDFN-6 | UDFN-6 - same | UDFN-6 - same | X2SON-6 - pin-compatible |
| Brand | STMicroelectronics | STMicroelectronics | STMicroelectronics | Texas Instruments |
| Output Voltage | 3.3V | 3.3V | 2.8V | 3.3V |
| Output Current | 300mA | 300mA | 300mA | 300mA |
| Dropout Voltage | 120mV | 120mV | 120mV | 150mV |
| Output Noise | 10 uVrms | 10 uVrms | 10 uVrms | 12 uVrms |
| PSRR at 1kHz | 70dB | 70dB | 70dB | 65dB |
| Quiescent Current | 40uA | 40uA | 40uA | 25uA |
| Enable Pin | Yes | Yes | Yes | Yes |
Key Differentiators
- Ultra-low noise of 10 uVrms (vs TPS7A2033PDSNR)
- Higher PSRR of 70 dB at 1 kHz (vs TPS7A2033PDSNR)
- Automotive grade option available (vs LD39030DTPU28R)
Design Notes
Place input and output capacitors as close to the IC pins as possible. Use a 1uF ceramic capacitor on the input and a 1uF ceramic capacitor on the output. Add a 0.1uF ceramic capacitor in parallel for high-frequency noise bypass. The UDFN-6 package has an exposed pad that should be soldered to a ground plane for optimal thermal performance.
At VIN=5V, VOUT=3.3V, and 300mA load, power dissipation is 510mW. With a thermal resistance of 90 C/W (theta_JA), the junction temperature rise is approximately 46C above ambient. For reliable operation at high ambient temperatures, ensure adequate copper area on the PCB to dissipate heat.
Do not exceed the maximum input voltage of 5.5V. Ensure the enable pin is not left floating; tie it to VIN if not used. The output capacitor must have a minimum capacitance of 1uF for stability. Using a capacitor with high ESR can cause oscillation.
Compliance Information
RoHS compliant per STMicroelectronics product page. Not AEC-Q100 qualified - choose LD39030DTPU33R-Q1 for automotive.
