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STMicroelectronics LD39100PUR
- Part No.:
- LD39100PUR
- Manufacturer:
- STMicroelectronics
- Package:
- 6-VDFN Exposed Pad
- Datasheet:
-
LD39100PUR.pdf
- Description:
- IC REG LINEAR POS ADJ 1A 6DFN
- Quantity:
- Payment:
- Shipping:
Inventory:30,815
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Product details
Overview
LD39100PUR from STMicroelectronics is an AEC-Q100 qualified ultra-low-dropout linear regulator delivering 1 A output current with 200 mV typical dropout at full load, 20 µA quiescent current at no load, and 30 µVRMS output noise at 0.8 V without bypass capacitor. It operates from 1.5 V to 5.5 V input and supports fixed or adjustable outputs (0.8–4.5 V), targeting automotive post-regulation and battery-powered consumer electronics.
For engineers reviewing the LD39100PUR datasheet, LD39100PUR pinout, LD39100PUR application, or LD39100PUR equivalent, key selection criteria include its ±2.0% output tolerance at 25 °C, logic-controlled shutdown (<1 µA off-mode current), stability with 1 µF ceramic output capacitors, and thermal/short-circuit protection in DFN6 (3×3 mm) wettable flank package.
Technical Context
The LD39100PUR integrates a precision bandgap reference, error amplifier, and PMOS pass transistor to achieve ultra-low dropout and low-noise regulation. Its internal current-limiting and thermal shutdown circuitry activate at 2.5 A short-circuit current and 160 °C junction temperature with 20 °C hysteresis.
It features dual protection-aware control signals: EN pin enables/disables regulation with 0.4 V logic-low threshold and 0.9 V logic-high threshold; PG pin provides open-drain power-good indication with rising-edge threshold at 0.92×VOUT and falling-edge at 0.80×VOUT, requiring external pull-up (100 kΩ–1 MΩ).
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output current | 1 A guaranteed - supports high-current microcontroller cores or FPGA I/O banks without derating at 125 °C ambient. |
| Dropout voltage | 200 mV typ. at 1 A - enables regulation from 1.5 V input down to 1.3 V output, critical for Li-ion single-cell systems. |
| Quiescent current | 20 µA typ. at no load - extends battery life in always-on automotive modules (e.g., CAN transceiver standby). |
| Output noise | 30 µVRMS (10 Hz–100 kHz) at 0.8 V - eliminates need for external bypass capacitor, reducing BOM count and PCB area. |
| PSRR | 70 dB at 1 kHz - suppresses ripple from upstream switching regulators in multi-rail power architectures. |
| Operating temp. | −40 °C to +125 °C - meets automotive Grade 1 requirements for under-hood and infotainment subsystems. |
| Package | DFN6 (3×3 mm) with wettable flanks - enables automated optical solder-joint inspection for automotive production traceability. |
Pinout & Package
LD39100PUR uses a 6-pin DFN6 (3×3 mm) package with exposed thermal pad connected to GND. Pin 1 is EN; Pin 2 is GND; Pin 3 is PG; Pin 4 is VOUT; Pin 5 is NC (fixed version) or ADJ (adjustable version); Pin 6 is VIN. The exposed pad must be soldered to a GND copper pour for thermal and electrical integrity.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| EN (Pin 1) | Logic enable input | Active-high control: <0.4 V = shutdown (<1 µA IQ), >0.9 V = active; no internal pull-up - requires external bias if unused. |
| GND (Pin 2) | Power and signal ground | Common return for all internal circuits; connects to exposed thermal pad - mandatory for thermal performance and noise immunity. |
| PG (Pin 3) | Open-drain power-good flag | High-impedance when VOUT ≥ 0.92×VOUT; low when ≤ 0.80×VOUT; sinks up to 6 mA - requires external pull-up to VIN or VOUT. |
| VOUT (Pin 4) | Regulated output | Delivers stable voltage (0.8–4.5 V fixed or adjustable); stable with 1 µF ceramic capacitor; low ESR range: 0–150 mΩ. |
| NC / ADJ (Pin 5) | No-connect (fixed) or adjust (adjustable) | Fixed version: pin left unconnected; adjustable version: sets output via resistor divider (VOUT = 0.8 V × (1 + R1/R2)). |
| VIN (Pin 6) | Input supply | Accepts 1.5–5.5 V DC; requires ≥1 µF low-ESR ceramic capacitor placed adjacent to pin for transient response and stability. |
Key Features
| Feature | Design Value |
|---|---|
| AEC-Q100 qualification | Grade 1 (−40 °C to +125 °C) - certified for automotive power rails including body control modules and ADAS sensors. |
| Ultra-low-noise operation | 30 µVRMS at 0.8 V without bypass cap - eliminates 2nd-stage filtering, simplifying layout for noise-sensitive analog/RF ICs. |
| Low-IQ across load range | 20 µA (no load) to 200 µA (1 A) - maintains efficiency during deep-sleep MCU states while supporting fast wake-up. |
| Stable with minimal capacitance | 1 µF ceramic COUT (X5R/X7R) - reduces cost and footprint vs. traditional LDOs requiring ≥10 µF tantalum. |
| Integrated protections | Thermal shutdown (160 °C, 20 °C hysteresis) + constant-current short-circuit limit (2.5 A) - enables robust operation without external circuitry. |
Applications
| Automotive Post-Regulation | Portable Gaming Consoles |
|---|---|
|
Use Scenario: Powering infotainment SoC I/O rails after a primary buck converter. IC Role / Device Role / Timing Role: Low-noise, high-PSRR post-regulator maintaining clean 1.8 V or 3.3 V for HDMI PHY and DDR I/O. Use Value: 70 dB PSRR at 1 kHz rejects switching noise from upstream 2 MHz buck, preventing bit errors in high-speed interfaces. |
Use Scenario: Supplying ARM Cortex-A CPU core voltage in handheld game devices. IC Role / Device Role / Timing Role: Adjustable LDO delivering 0.8–1.2 V at up to 1 A with dynamic voltage scaling support. Use Value: 200 mV dropout enables full 1 A operation even as Li-Po battery discharges from 4.2 V to 3.0 V. |
| USB-C Peripheral Power | Industrial Printers |
|
Use Scenario: Regulating 5 V USB-C PD input to 3.3 V for MCU and sensor subsystems. IC Role / Device Role / Timing Role: Input-supply tolerant LDO (1.5–5.5 V) with enable control synchronized to USB enumeration. Use Value: 20 µA quiescent current ensures <1 week standby on coin-cell backup when main USB power is removed. |
Use Scenario: Providing stable 2.5 V for stepper motor driver logic and encoder interface. IC Role / Device Role / Timing Role: High-reliability LDO with thermal protection operating in enclosed, high-ambient-temperature printer chassis. Use Value: −40 °C to +125 °C rating and 160 °C thermal shutdown prevent latch-up during continuous print jobs. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| Torex XC6210B122MR-G | 0.8 V to 5.0 V adjustable; 150 mV dropout at 1 A; 25 µA IQ; no PG pin; SOT-23-5 package. | Lacks power-good monitoring and automotive qualification; limited to commercial-temp applications. | Select when PG signal is unnecessary and space-constrained SOT-23 layout is preferred over DFN6. |
| Analog Devices ADM7172ACPZ-R7 | 2 A output; 175 mV dropout; 35 µA IQ; 10 µVRMS noise; 20 V max input; LFCSP-10 package. | Higher voltage rating and lower noise, but larger package and higher cost; not AEC-Q100 qualified. | Choose for ultra-low-noise industrial instrumentation where 2 A current and 20 V input margin are required. |
Compared with XC6210B122MR-G and ADM7172ACPZ-R7, LD39100PUR uniquely combines AEC-Q100 Grade 1 qualification, wettable-flank DFN6 for automotive process control, and integrated PG/EN logic - making it optimal for cost-sensitive, safety-aware automotive and industrial edge nodes.
Availability
LD39100PUR is available at Aetrix Electronics and suitable for automotive post-regulation, portable gaming consoles, USB-C peripheral power, and industrial printers requiring stable component supply across extended temperature ranges and long product lifecycles.
Supply support for LD39100PUR 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 microcontrollers, power management ICs, and automotive-grade analog components for industrial, automotive, and consumer markets.
LD39100PUR belongs to ST's high-performance LDO family engineered specifically for automotive and battery-powered applications demanding ultra-low dropout, low quiescent current, and AEC-Q100 reliability.
FAQ
What is the minimum output capacitance required for LD39100PUR stability?
The LD39100PUR is stable with a minimum 1 µF ceramic output capacitor (X5R or X7R dielectric) having ESR between 0 and 150 mΩ. This value is validated across −40 °C to +125 °C and ensures no ringing or oscillation during load transients up to 1 A step change. Larger values improve transient response but are not required for stability.
Can LD39100PUR be used with an adjustable output voltage below 1.5 V?
Yes - the adjustable version supports outputs as low as 0.8 V using the ADJ pin and external resistor divider. However, dropout voltage specification (200 mV typ.) applies only to VOUT > 1.5 V per datasheet Table 6 footnote 2; at 0.8 V, dropout is characterized separately and remains ≤350 mV at 1 A and 125 °C.
How does the Power Good (PG) pin behave during enable/disable transitions?
When EN is pulled low, the LD39100PUR enters shutdown and the PG pin goes to high-impedance state - intentionally avoiding sink current that could interfere with system-level power sequencing. When EN rises above 0.9 V, PG remains high-Z until VOUT reaches 92% of target, then transitions to high-Z (not driven high) - requiring external pull-up for logic-level signaling.
Is the exposed thermal pad electrically connected internally?
Yes - the exposed pad is internally connected to GND and must be soldered to a dedicated GND copper pour on the PCB. It serves both thermal dissipation (reducing RthJA from 55 °C/W to ~40 °C/W with 4× thermal vias) and electrical grounding for noise suppression; floating or unconnected pads cause thermal runaway and instability.
LD39100PUR Specifications
- Product attributes
- Attribute value
- Manufacturer:
- STMicroelectronics
- Series:
- -
- Package/Case:
- 6-VDFN Exposed Pad
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Output Configuration:
- Positive
- Output Type:
- Adjustable
- Number of Regulators:
- 1
- Voltage - Input (Max):
- 5.5V
- Voltage - Output (Min/Fixed):
- 0.8V
- Voltage - Output (Max):
- 4.6V
- Voltage Dropout (Max):
- 0.4V @ 1A
- Current - Output:
- 1A
- Current - Quiescent (Iq):
- 50 µA
- Current - Supply (Max):
- 300 µA
- PSRR:
- 70dB ~ 65dB (1kHz ~ 10kHz)
- Control Features:
- Enable, Power Good
- Protection Features:
- Over Current, Over Temperature, Short Circuit
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- 6-DFN (3x3)
LD39100PUR FAQ
1.How can I place an order for LD39100PUR through Aetrix?
Please submit a Request for Quotation (RFQ) for LD39100PUR 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 LD39100PUR reliable?
The price and inventory of LD39100PUR are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LD39100PUR is usually 5 days.
3.What payment methods are accepted for LD39100PUR?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LD39100PUR transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LD39100PUR?
LD39100PUR orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LD39100PUR 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 LD39100PUR?
For technical support, including LD39100PUR datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LD39100PUR requirements.
6.How does Aetrix verify that LD39100PUR is sourced from the original manufacturer or authorized distributors?
All LD39100PUR 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 LD39100PUR meets industry standards.
7.What is the process for return or replacement of LD39100PUR?
All LD39100PUR units undergo pre-shipment inspection (PSI). If there is an issue with LD39100PUR, 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 LD39100PUR part is unused and in its original packaging.
Return procedure for LD39100PUR:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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