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STMicroelectronics LDR2533PT-R
- Part No.:
- LDR2533PT-R
- Manufacturer:
- STMicroelectronics
- Package:
- TO-252-5, DPAK (4 Leads + Tab), TO-252AD
- Datasheet:
-
LDR2533PT-R.pdf
- Description:
- IC REG LINEAR 2.5V/3.3V PPAK
- Quantity:
- Payment:
- Shipping:
Inventory:1,126
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Product details
Overview
LDR2533PT-R from STMicroelectronics is a dual low-dropout linear voltage regulator IC with independent logic-controlled shutdown, delivering 2.5 V/3.3 V outputs at up to 500 mA and 1.0 A respectively. It features 0.3 V dropout at 500 mA (VO1), 0.4 V at 1 A (VO2), 70 dB supply voltage rejection, and operates across –40 °C to +125 °C - used in PDA power rails and set-top-box dual-supply systems.
For engineers reviewing the LDR2533PT-R datasheet, LDR2533PT-R pinout, LDR2533PT-R application, or LDR2533PT-R equivalent, key selection criteria include per-channel enable control, low-quiescent-current operation (1.6 mA max ON, 50 µA OFF), stable performance with 4.7 µF low-ESR output capacitors, and thermal/current limiting for robust embedded power management.
Technical Context
This dual LDO integrates two independent regulator channels-each with dedicated bandgap reference, error amplifier, driver, and power transistor-enabling simultaneous 2.5 V and 3.3 V generation from separate input supplies (VI1, VI2). Shutdown pins INH1 and INH2 are TTL-compatible and electrically isolated between channels.
Designed for high-voltage tolerance (up to 15 V input), it employs internal current and thermal limiting, supports low-noise operation (0.003 %VO RMS noise), and maintains regulation under wide line/load transients-validated with CI = 2.2 µF, CO = 4.7 µF ceramic capacitors.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| VO1 / VO2 | 2.5 V ±5 % / 3.3 V ±5 % - tightly regulated dual outputs enabling core/I/O rail separation in portable electronics |
| IO1 / IO2 | 500 mA / 1.0 A - asymmetric current capability matches typical microprocessor core (2.5 V) and peripheral (3.3 V) load profiles |
| VDROP1 / VDROP2 | 0.3 V @ 500 mA / 0.4 V @ 1 A - enables operation from low headroom inputs (e.g., single-cell Li-ion or 5 V bus) |
| SVR | 70 dB @ 120 Hz - suppresses ripple from noisy DC-DC pre-regulators feeding VI1/VI2 |
| Quiescent Current | 1.6 mA max (ON), 50 µA (OFF) - minimizes standby power in battery-backed systems with selective channel disable |
| Operating Temp | –40 °C to +125 °C - qualified for industrial and consumer ambient environments without derating |
| Capacitor Support | Stable with ≥4.7 µF ceramic output caps (low ESR) - eliminates need for bulky tantalum or aluminum electrolytics |
Pinout & Package
Supplied in PPAK (Power Package) - thermally enhanced surface-mount package with exposed thermal pad (RthJC = 8 °C/W), RoHS-compliant and ECOPACK® certified.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| 1 - VI2 | Input supply pin for VO2 channel | Bypass with 2.2 µF capacitor to GND; accepts up to 15 V DC - powers 3.3 V/1 A output stage |
| 2 - VI1 | Input supply pin for VO1 channel | Bypass with 2.2 µF capacitor to GND; accepts up to 15 V DC - powers 2.5 V/500 mA output stage |
| 3 - GND | Common ground reference | Shared return path for both regulators and bypass capacitors - critical for noise coupling control |
| 4 - VO1 | Output pin for 2.5 V regulator | Delivers regulated 2.5 V; requires ≥4.7 µF ceramic cap to GND for stability and transient response |
| 5 - VO2 | Output pin for 3.3 V regulator | Delivers regulated 3.3 V; requires ≥4.7 µF ceramic cap to GND - supports higher current loads than VO1 |
Key Features
| Feature | Design Value |
|---|---|
| Dual independent shutdown | TTL-compatible INH1/INH2 pins allow selective channel disable - reduces total system quiescent current to 50 µA when both off |
| Low-noise regulation | 0.003 %VO RMS output noise (10 Hz–100 kHz) - suitable for analog-sensitive circuits like ADC references or RF bias rails |
| Thermal & current protection | Internal foldback current limit and thermal shutdown prevent damage during overload or poor heatsinking - no external components required |
| High PSRR | 70 dB supply voltage rejection at 120 Hz - maintains clean output despite ripple on VI1/VI2 from upstream switching converters |
| Wide input voltage range | –0.3 V to +15 V absolute max on VI1/VI2 - accommodates varied pre-regulator topologies and transient overvoltage conditions |
Applications
| PDA Power Management | Set-Top Box Dual Rail |
|---|---|
Use Scenario: Portable digital assistant requiring separate 2.5 V core and 3.3 V I/O supplies from a single Li-ion battery or 5 V adapter. IC Role / Device Role / Timing Role: Dual LDO regulator providing independently enabled, low-noise, low-dropout DC-DC conversion with thermal safety. Use Value: Enables extended battery life via ultra-low OFF-mode current (50 µA) and efficient light-load regulation without external supervision circuitry. |
Use Scenario: Consumer set-top box needing isolated 2.5 V (decoder ASIC) and 3.3 V (HDMI interface, memory) rails from a shared 5 V or 12 V supply. IC Role / Device Role / Timing Role: Dual-channel linear regulator with independent enable control and high PSRR to reject switching noise from upstream DC-DC stages. Use Value: Eliminates need for two discrete LDOs and associated layout area; 70 dB SVR ensures HDMI signal integrity and decoder stability. |
| Microdrive Power Supply | Industrial Controller I/O Rail |
Use Scenario: Compact hard disk drive module (Microdrive) powered from 3.3 V or 5 V source, requiring clean 2.5 V spindle motor control and 3.3 V logic supply. IC Role / Device Role / Timing Role: Dual LDO delivering tightly regulated, low-noise outputs with fast load transient response (<10 µs recovery). Use Value: Meets stringent noise and dropout requirements of rotating media drivers while supporting thermal shutdown during stall conditions. |
Use Scenario: Programmable logic controller (PLC) I/O module needing robust 2.5 V sensor interface and 3.3 V communication rail in harsh industrial environments. IC Role / Device Role / Timing Role: High-temperature-rated (–40 °C to +125 °C) dual LDO with internal current limiting and stable ceramic-capacitor operation. Use Value: Ensures reliable operation across wide ambient temperature swings without external thermal monitoring or derating. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar dual-LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TPS7A8300RTJR | Lower dropout (0.12 V @ 1 A), higher PSRR (75 dB), but fixed 3.3 V/1.2 V outputs and no independent shutdown | Requires external level-shifting for 2.5 V logic; better suited for high-PSRR FPGA core/I/O where output voltages match | Select if PSRR >70 dB and ultra-low dropout are prioritized over flexible output pairing and per-channel enable |
| NCP1117DTADJG | Single adjustable-output LDO (1 A), no dual-channel integration, no shutdown control, higher dropout (1.2 V) | Needs two devices plus external resistors to replicate LDR2533PT-R functionality - increases BOM count and PCB area | Choose only for cost-sensitive, non-thermal-critical applications where dual-channel integration and low dropout are not required |
Compared with TPS7A8300RTJR and NCP1117DTADJG, LDR2533PT-R uniquely combines matched 2.5 V/3.3 V outputs, independent TTL shutdown, and sub-0.4 V dropout in one PPAK package - simplifying design for portable and consumer dual-rail systems without sacrificing thermal or noise performance.
Availability
LDR2533PT-R is available at Aetrix Electronics and suitable for PDA power management, set-top-box dual-rail systems, and Microdrive applications requiring stable component supply, long-lifecycle support, and automotive-grade temperature resilience.
Supply support for LDR2533PT-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 analog, MCU, power, and sensor solutions for industrial, automotive, and consumer markets.
LDR2533PT-R belongs to ST's legacy linear regulator product line, engineered specifically for low-noise, low-power dual-rail applications in portable and consumer electronics where space, thermal efficiency, and supply rejection are critical.
FAQ
What is the maximum input voltage rating for LDR2533PT-R?
The absolute maximum DC input voltage for both VI1 and VI2 pins is –0.3 V to +15 V. Operation above VOx + 7 V is not recommended per electrical characteristics test conditions; sustained voltage beyond 12 V may accelerate aging or reduce reliability. Thermal derating applies above 125 °C junction temperature.
Can LDR2533PT-R operate with ceramic output capacitors only?
Yes - the device is explicitly characterized and guaranteed stable with ≥4.7 µF ceramic capacitors (low ESR) on VO1 and VO2. No series resistance or electrolytic supplementation is required. ST validates stability using X5R/X7R dielectrics per typical application circuit (Figure 3).
How does the shutdown function behave electrically?
INH1 and INH2 are active-high TTL-compatible inputs: VO1/VO2 turn on when voltage ≥2.4 V and shut down when ≤0.8 V. Each pin draws ≤6 µA at 5 V. There is no internal pull-up; external logic or microcontroller GPIO must drive them directly.
Is LDR2533PT-R still in active production?
No - STMicroelectronics has marked LDR2533PT-R as obsolete (per document header and revision history). Aetrix Electronics holds remaining authorized inventory and provides last-time-buy support, including full traceability, datasheet validation, and engineering guidance for migration paths.
LDR2533PT-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:
- 2
- Voltage - Input (Max):
- 15V
- Voltage - Output (Min/Fixed):
- 2.5V, 3.3V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 0.8V @ 1A
- Current - Output:
- 500mA, 1A
- Current - Quiescent (Iq):
- 50 µA
- Current - Supply (Max):
- 1.6 mA
- PSRR:
- 70dB (120Hz)
- Control Features:
- Enable
- Protection Features:
- Over Current, Over Temperature, Short Circuit
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- PPAK
LDR2533PT-R FAQ
1.How can I place an order for LDR2533PT-R through Aetrix?
Please submit a Request for Quotation (RFQ) for LDR2533PT-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 LDR2533PT-R reliable?
The price and inventory of LDR2533PT-R are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LDR2533PT-R is usually 5 days.
3.What payment methods are accepted for LDR2533PT-R?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LDR2533PT-R transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LDR2533PT-R?
LDR2533PT-R orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LDR2533PT-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 LDR2533PT-R?
For technical support, including LDR2533PT-R datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LDR2533PT-R requirements.
6.How does Aetrix verify that LDR2533PT-R is sourced from the original manufacturer or authorized distributors?
All LDR2533PT-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 LDR2533PT-R meets industry standards.
7.What is the process for return or replacement of LDR2533PT-R?
All LDR2533PT-R units undergo pre-shipment inspection (PSI). If there is an issue with LDR2533PT-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 LDR2533PT-R part is unused and in its original packaging.
Return procedure for LDR2533PT-R:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
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