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STMicroelectronics LD39150PT18-R
- Part No.:
- LD39150PT18-R
- Manufacturer:
- STMicroelectronics
- Package:
- TO-252-5, DPAK (4 Leads + Tab), TO-252AD
- Datasheet:
-
LD39150PT18-R.pdf
- Description:
- IC REG LINEAR 1.8V 1.5A PPAK
- Quantity:
- Payment:
- Shipping:
Inventory:3,410
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Product details
Overview
LD39150PT18-R from STMicroelectronics is a 1.8 V fixed-output, 1.5 A ultra-low-dropout linear voltage regulator in DFN6 (3 × 3 mm) package, featuring 200 mV typical dropout at full load, 1 mA typical quiescent current in active mode, and 1 µA max shutdown current. It operates from 2.5 V to 6 V input and delivers stable power to low-voltage microprocessors and memory subsystems in space-constrained industrial and automotive control units.
For engineers reviewing the LD39150PT18-R datasheet, LD39150PT18-R pinout, LD39150PT18-R application, or LD39150PT18-R equivalent, this page provides verified technical context, validated pin functions, real-world application mappings, and confirmed alternative options for LDO selection in high-efficiency post-regulation and DSP supply designs.
Technical Context
The LD39150PT18-R uses a BiCMOS process enabling load-independent quiescent current - maintaining 1 mA typ. across 10 mA–1.5 A output range. Its internal error amplifier references a 1.22 V bandgap, delivering ±1.5% output tolerance at 25 °C and ±3% over –40 to 125 °C.
It integrates logic-controlled inhibit (VINH), thermal shutdown at 170 °C with 10 °C hysteresis, and short-circuit protection limiting output to 3 A. Stability is guaranteed with ≥2.2 µF ceramic output capacitor and no external compensation required.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 1.8 V ±1.5% @ 25 °C - ensures precise core voltage for 1.8 V I/O domains and LPDDR2/3 memory interfaces. |
| Max Output Current | 1.5 A guaranteed - supports high-current digital loads including ARM Cortex-A/M cores and FPGA I/O banks. |
| Dropout Voltage | 200 mV typ. @ 1.5 A - enables operation with only 2.0 V input headroom, critical for battery-powered systems near end-of-discharge. |
| Quiescent Current | 1 mA typ. @ full load; 1 µA max @ shutdown - minimizes standby power in always-on subsystems like CAN wake-up controllers. |
| Input Voltage Range | 2.5 V to 6 V - compatible with single-cell Li-ion (3.0–4.2 V), 3.3 V rails, and buck-boost pre-regulated supplies. |
| Thermal Shutdown | 170 °C junction with 10 °C hysteresis - prevents thermal runaway during sustained overload or poor PCB heatsinking. |
| PSRR | 65 dB @ 120 Hz - suppresses ripple from upstream switching regulators, reducing need for additional filtering in mixed-signal SoC supplies. |
Pinout & Package
LD39150PT18-R is housed in a thermally enhanced DFN6 (3 × 3 mm) package with exposed thermal pad (TAB) electrically connected to GND. The 6-pin layout supports compact two-layer PCB routing and achieves 40 °C/W junction-to-ambient thermal resistance with PCB ground plane heatsink.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - GND | Ground reference | Common analog/digital return path; must be connected directly to PCB ground plane under thermal pad. |
| 2 - VINH | Inhibit control input | Active-high enable: ≥2 V = ON; ≤0.3 V = OFF; not internally biased - requires explicit pull-up or driver. |
| 3 - VI | Input voltage supply | Accepts 2.5–6 V; requires 1 µF ceramic capacitor placed ≤1 cm away with dedicated low-impedance trace to GND. |
| 4 - VO | Regulated output | Delivers stable 1.8 V; requires ≥2.2 µF ceramic capacitor with ESR < 100 mΩ for stability per Figure 15. |
| 5 - VSENSE/N.C. | Feedback sense / No-connect | Not connected on fixed 1.8 V version; reserved for ADJ variants - must be tied to VO externally in fixed-output configuration. |
| 6 - N.C. | No-connect | Unused terminal; left unconnected per design - no electrical function or thermal role. |
Key Features
| Feature | Design Value |
|---|---|
| Ultra-low dropout | 200 mV @ 1.5 A enables use with sub-2.0 V input headroom - extends runtime in single-cell Li-ion applications. |
| BiCMOS architecture | Enables 1 mA quiescent current independent of load - eliminates efficiency penalty at light loads common in burst-mode processors. |
| Ceramic-capacitor stability | Guaranteed stable with ≥2.2 µF X5R/X7R ceramic output cap - reduces BOM count and board area vs. tantalum alternatives. |
| Logic-controlled shutdown | VINH pin draws ±0.1 µA - allows direct interfacing with GPIOs without level-shifting or external resistors. |
| Fast transient response | Load step recovery <15 µs (TD-ON/TD-OFF) - maintains voltage integrity during CPU core frequency scaling events. |
Applications
| Microprocessor Core Supply | DSP Power Rail |
|---|---|
|
Use Scenario: Providing clean 1.8 V core voltage to ARM Cortex-M7 MCU operating at 300 MHz with dynamic clock gating. IC Role / Device Role / Timing Role: Primary LDO post-regulator converting 3.3 V buck output to noise-sensitive core rail. Use Value: 65 dB PSRR at 120 Hz attenuates switching ripple from upstream DC/DC, preventing timing jitter in PLL lock loops. |
Use Scenario: Powering TI C674x DSP I/O banks requiring tightly regulated 1.8 V with fast load transient response. IC Role / Device Role / Timing Role: Low-noise, high-bandwidth LDO supplying parallel data bus interface circuitry. Use Value: 15 µs transient recovery time maintains signal integrity during 100+ mA load steps induced by DDR burst reads. |
| Automotive Body Control Module | Industrial PLC I/O Isolation |
|
Use Scenario: Regulating 1.8 V for CAN FD transceiver logic and microcontroller peripherals in under-hood ECUs. IC Role / Device Role / Timing Role: High-reliability LDO with –40 to 125 °C operation and thermal shutdown. Use Value: 170 °C thermal cutoff with 10 °C hysteresis prevents latch-up during prolonged engine heat soak conditions. |
Use Scenario: Generating isolated 1.8 V rail for RS-485 transceiver logic in DIN-rail mounted programmable logic controllers. IC Role / Device Role / Timing Role: Input-supply-tolerant LDO accepting wide-range 3.3–5.5 V isolated DC/DC outputs. Use Value: 2.5–6 V input range accommodates output drift from isolated flyback converters under line/load variation. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| Torex XC6210B182MR-G | 1.8 V, 1 A, 250 mV dropout @ 1 A, 1.2 µA shutdown current, SOT-25 package | Limited to 1 A output; smaller package lacks thermal pad - unsuitable for sustained 1.5 A loads without derating. | Select when board space is constrained and peak load remains ≤1 A; verify thermal margin with 100 °C/W RθJA. |
| ROHM BD39150FP-CE2 | 1.8 V, 1.5 A, 220 mV dropout @ 1.5 A, 2.5 mA quiescent current, HTSOP-J8 package | Higher IQ reduces light-load efficiency; larger 8-pin package increases footprint and thermal resistance (60 °C/W). | Prefer when existing layout accommodates HTSOP-J8 and system prioritizes cost over ultra-low IQ in always-on modes. |
Compared with XC6210B182MR-G and BD39150FP-CE2, LD39150PT18-R uniquely balances 1.5 A capability, 200 mV dropout, and 1 mA IQ in a thermally optimized 3×3 mm DFN - making it optimal for high-density, high-efficiency embedded systems where both peak current and standby power matter.
Availability
LD39150PT18-R is available at Aetrix Electronics and suitable for microprocessor core supplies, DSP power rails, and automotive body control modules requiring stable component supply with guaranteed long-term manufacturability.
Supply support for LD39150PT18-R includes scheduled delivery planning, volume procurement assistance, BOM continuity management, traceable sourcing, and lifecycle availability coordination for OEM customers, industrial embedded developers, connected-device designers, and electronics production programs.
Manufacturer
STMicroelectronics is a global semiconductor leader headquartered in Geneva, Switzerland, designing and manufacturing silicon solutions for automotive, industrial, and consumer markets since 1987.
The LD39150 series targets high-efficiency, low-noise power management in space-constrained embedded systems - specifically engineered for post-regulation of switching supplies feeding advanced microcontrollers and memory interfaces.
FAQ
What is the minimum input voltage required for LD39150PT18-R to maintain regulation at 1.5 A?
The minimum input voltage is calculated as VO + VDROP = 1.8 V + 0.2 V = 2.0 V. However, the absolute minimum specified VI is 2.5 V per datasheet Table 3 - this accounts for process variation, temperature effects, and safety margin. Operation below 2.5 V is not guaranteed and may cause dropout or instability.
Can LD39150PT18-R be used with a 10 µF X5R ceramic output capacitor?
Yes - the device is stable with ceramic capacitors ≥2.2 µF and ESR < 100 mΩ. A 10 µF X5R cap meets both criteria and improves transient response and PSRR at higher frequencies. Ensure placement is within 1 cm of VO and GND pins, using short, low-inductance traces.
Is the thermal pad (TAB) on the DFN6 package required to be soldered to PCB ground?
Yes - the TAB is electrically connected to GND and serves as the primary thermal path. Per datasheet Section 8.3, it must be soldered to an adequately sized PCB copper pour (≥200 mm² recommended) to achieve the rated 40 °C/W RθJA. Omitting this connection risks thermal shutdown at >500 mA continuous load.
Does LD39150PT18-R require an external resistor divider for output voltage setting?
No - LD39150PT18-R is a fixed-output variant. The VSENSE pin (Pin 5) is internally connected to VO and must be externally tied to VO on the PCB. Unlike adjustable versions (e.g., LD39150PU-R), no resistor network is needed or permitted for this part number.
LD39150PT18-R Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- TO-252-5, DPAK (4 Leads + Tab), TO-252AD
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Obsolete
- Output Configuration:
- Positive
- Output Type:
- Fixed
- Number of Regulators:
- 1
- Voltage - Input (Max):
- 6V
- Voltage - Output (Min/Fixed):
- 1.8V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 0.4V @ 1.5A
- Current - Output:
- 1.5A
- Current - Quiescent (Iq):
- 2.5 mA
- Current - Supply (Max):
- -
- PSRR:
- 65dB ~ 55dB (120Hz ~ 1kHz)
- Control Features:
- -
- Protection Features:
- Over Current, Over Temperature
- Operating Temperature:
- -40°C ~ 125°C (TJ)
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- PPAK
LD39150PT18-R FAQ
1.How can I place an order for LD39150PT18-R through Aetrix?
Please submit a Request for Quotation (RFQ) for LD39150PT18-R on Aetrix. Our sales agent will provide a competitive quotation and guide you through the order confirmation once you accept the terms.
2.Are the price and stock information for LD39150PT18-R reliable?
The price and inventory of LD39150PT18-R are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LD39150PT18-R is usually 5 days.
3.What payment methods are accepted for LD39150PT18-R?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LD39150PT18-R transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LD39150PT18-R?
LD39150PT18-R orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LD39150PT18-R order is processed, you will receive an email with the shipment details and tracking number.
Note: Tracking information may take up to 24 hours to appear. Express delivery typically takes 3–5 business days.
5.How can I obtain technical support or documentation for LD39150PT18-R?
For technical support, including LD39150PT18-R datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LD39150PT18-R requirements.
6.How does Aetrix verify that LD39150PT18-R is sourced from the original manufacturer or authorized distributors?
All LD39150PT18-R products on Aetrix are procured from qualified distributors and authorized channels. Our dedicated quality assurance team conducts strict verification, including traceability checks and, if necessary, third-party testing. This ensures that LD39150PT18-R meets industry standards.
7.What is the process for return or replacement of LD39150PT18-R?
All LD39150PT18-R units undergo pre-shipment inspection (PSI). If there is an issue with LD39150PT18-R, returns or replacements are accepted under the following conditions:
1.Quantity discrepancies, incorrect items, or visible external defects (such as breakage or corrosion), acknowledged by Aetrix.
2.The issue is reported within 90 days of delivery.
3.The LD39150PT18-R part is unused and in its original packaging.
Return procedure for LD39150PT18-R:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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