My Inquiry
My Account
Texas Instruments LP2957AISX/NOPB
- Part No.:
- LP2957AISX/NOPB
- Manufacturer:
- Texas Instruments
- Package:
- TO-263-6, D2PAK (5 Leads + Tab), TO-263BA
- Datasheet:
-
LP2957AISX/NOPB.pdf
- Description:
- IC REG LIN 5V 250MA DDPAK/TO263
- Quantity:
- Payment:
- Shipping:
Inventory:1,048
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LP2957AISX/NOPB from Texas Instruments is a 5V fixed-output, low-dropout linear regulator with electronic shutdown, error flag output, and snap-on/snap-off programmability-designed for microprocessor power supply applications. It delivers 250 mA output current with 470 mV typical dropout at 250 mA, 150 µA quiescent current at 1 mA load, and ±1.4% output accuracy over temperature (A-grade).
For engineers reviewing the LP2957AISX/NOPB datasheet, LP2957AISX/NOPB pinout, LP2957AISX/NOPB application, or LP2957AISX/NOPB equivalent, key selection criteria include guaranteed 250 mA output, tight line/load regulation (0.04% typical), reverse-battery protection, thermal/current limiting, and programmable hysteresis for clean power sequencing in battery- and transformer-powered µP systems.
Technical Context
The LP2957AISX/NOPB integrates a precision 5V bandgap reference, error amplifier, pass transistor, and dedicated comparators for shutdown control and dropout detection. Its internal architecture supports snap-on/snap-off operation via external resistor networks to eliminate intermediate voltage states during power-up/down transitions.
It features an open-collector error flag that asserts LOW when output falls >5% out of regulation-triggered by low input, current limit, or thermal shutdown-and includes reverse-battery protection on the input pin, ensuring safe operation even with inverted supply polarity.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | 5.0 V ±1.4% over −40°C to +125°C (A-grade); enables stable µP core logic without external trimming. |
| Max Output Current | 250 mA ensured; sufficient for mid-complexity microcontrollers and peripheral ICs in portable systems. |
| Dropout Voltage | 470 mV typical at 250 mA; allows operation with VIN as low as 5.47 V while maintaining regulation. |
| Quiescent Current | 150 µA typical at 1 mA load; minimizes standby power loss in battery-backed applications. |
| Line/Load Regulation | 0.04% typical; maintains tight output stability despite input ripple or dynamic load changes. |
| Thermal Coefficient | 20 ppm/°C typical; contributes <±2.5 mV drift over full temperature range-critical for ADC reference integrity. |
| Error Flag Threshold | Asserts LOW when VO drops >250 mV below nominal; provides reliable fault signaling for system monitoring. |
Pinout & Package
LP2957AISX/NOPB is housed in a 5-lead DDPAK/TO-263 surface-mount package (package code KTT0005B), thermally enhanced with exposed die pad for PCB heat sinking. Thermal resistance θJA is 73°C/W with standard layout, reducible to 32°C/W using ≥1.6 in² copper area.
| Pin/Terminal | Circuit Role | Design Meaning |
|---|---|---|
| IN | Input Supply | Accepts 6–30 V DC input; includes reverse-battery protection diode-no external polarity guard needed. |
| GND | Ground Reference | Common return for load, bias, and error flag; must be connected to system ground to prevent damage if output is externally biased. |
| OUT | Regulated Output | Delivers 5 V ±1.4%; requires ≥2.2 µF output capacitor (ESR ≤5 Ω) for stability across temperature and load. |
| SD | Shutdown Control | Active-low logic input; pulls regulator OFF when <1.2 V; requires pull-up to VIN if driven open-collector. |
| ERROR | Open-Collector Fault Flag | Sinks up to 400 µA when output is out-of-regulation; needs external pull-up (100 kΩ–1 MΩ) to VO or another rail. |
Key Features
| Feature | Design Value |
|---|---|
| Snap-on/Snap-off Programmability | Enables clean, hysteresis-controlled power sequencing using three external resistors-eliminates unstable mid-rail voltages during µP boot/reset. |
| Reverse Battery Protection | Internal diode prevents damage from −20 V input; removes need for external series diode and its associated 0.3–0.7 V drop. |
| Low Dropout at Full Load | 470 mV typical at 250 mA ensures usable headroom from 5.5 V sources (e.g., LiFePO₄ or 6 V transformer secondaries). |
| Output Crowbar Function | 50 mA typical pulldown current rapidly discharges output when SD is asserted or regulator snaps off-prevents floating bus states. |
| Thermal & Current Limiting | Internally protects against sustained overload or ambient overheating; enters safe thermal shutdown without latch-up. |
Applications
| Battery-Powered Microcontroller Systems | Transformer-Fed Industrial Controllers |
|---|---|
Use Scenario: Portable data logger powered by 4×AA alkaline cells (6 V fresh, ~4.8 V depleted) supplying an ARM Cortex-M0+ MCU and sensor interface. IC Role / Device Role / Timing Role: Primary 5 V LDO providing regulated core voltage with shutdown control tied to MCU GPIO for deep-sleep mode. Use Value: 150 µA quiescent current extends battery life; snap-off at 5.5 V prevents brownout-induced MCU lockup during cell depletion. | Use Scenario: PLC I/O module fed from 6.3 VAC transformer, rectified and filtered to unregulated DC, powering multiple 5 V peripherals. IC Role / Device Role / Timing Role: Final-stage regulator with programmable hysteresis to avoid oscillation during AC line sags or load surges. Use Value: 1.2 V hysteresis (set via R1/R2/R3) prevents chatter during 10% line dips; 0.04% load regulation maintains ADC reference accuracy. |
| Automotive Body Control Modules | Medical Handheld Diagnostics |
Use Scenario: Door module operating from vehicle battery (9–16 V), requiring reverse-polarity immunity and clean 5 V for CAN transceiver and microcontroller. IC Role / Device Role / Timing Role: Input-protected 5 V regulator with ERROR flag feeding watchdog timer to detect undervoltage faults. Use Value: Reverse-battery protection eliminates need for external Schottky; ERROR signal triggers safe state entry before µP resets. | Use Scenario: Portable ECG device using single-cell Li-ion (3.0–4.2 V) with boost converter followed by LP2957AISX/NOPB for ultra-low-noise analog front-end supply. IC Role / Device Role / Timing Role: Post-regulator delivering ultra-stable 5 V to op-amps and SAR ADC with <20 ppm/°C drift. Use Value: 500 µV RMS noise (10 Hz–100 kHz) and 20 ppm/°C TC ensure <1 LSB error in 12-bit medical-grade conversion. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar low-dropout regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| TSS721AIPW | 5 V fixed, 250 mA, but no shutdown or error flag; higher 250 µA IQ; TO-220 only. | Lacks programmable sequencing and fault reporting-suitable only for simple always-on supplies. | Select only if shutdown/error functionality is unnecessary and TO-220 mounting is preferred. |
| TPS76350QDBVRQ1 | AEC-Q100 qualified; 5 V, 150 mA; 120 µA IQ; integrated thermal shutdown; no snap-on/snap-off. | Automotive-qualified but lower current rating; no hysteresis programming-requires external circuitry for clean sequencing. | Choose for automotive production where AEC-Q100 compliance is mandatory and 150 mA suffices. |
Compared with TSS721AIPW and TPS76350QDBVRQ1, LP2957AISX/NOPB uniquely combines 250 mA output, integrated shutdown/error, and field-programmable snap-on/snap-off-enabling robust, self-contained power sequencing without external logic or comparators.
Availability
LP2957AISX/NOPB is available at Aetrix Electronics and suitable for battery-powered microcontroller systems, industrial PLC modules, automotive body electronics, and portable medical diagnostics requiring stable component supply, long-term lifecycle support, and traceable sourcing.
Supply support for LP2957AISX/NOPB 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
Texas Instruments is a global semiconductor leader specializing in analog, embedded processing, and high-reliability silicon solutions for industrial, automotive, and consumer markets.
The LP2957A product line was engineered specifically for µP power management-delivering precision 5 V regulation with integrated protection, sequencing, and fault signaling in compact surface-mount packages.
FAQ
What is the guaranteed output voltage tolerance of LP2957AISX/NOPB over temperature?
The LP2957AISX/NOPB is an A-grade device with guaranteed 5.0 V output within ±1.4% over the full −40°C to +125°C junction temperature range. This specification is verified per TI's SNVS102C datasheet, Table 1, and applies under 1 mA ≤ IL ≤ 250 mA load conditions. The LP2957AISX/NOPB achieves this via laser-trimmed bandgap reference and precision error amplifier design.
Does LP2957AISX/NOPB require an output capacitor, and what type is recommended?
Yes, LP2957AISX/NOPB requires a minimum 2.2 µF output capacitor connected between OUT and GND for stability. TI specifies tantalum or aluminum electrolytic capacitors with ESR ≤5 Ω and resonant frequency >500 kHz. Solid tantalum is recommended for operation below −25°C due to low-temperature electrolyte freezing in wet Al-elec types. The LP2957AISX/NOPB becomes unstable or may oscillate without this capacitor.
How does the ERROR pin on LP2957AISX/NOPB function, and what external components are needed?
ERROR is an open-collector output that sinks up to 400 µA when the regulated output falls >5% (i.e., >250 mV) out of regulation. It requires an external pull-up resistor-TI recommends 100 kΩ to 1 MΩ connected to VO (not an external rail) to avoid invalid HIGH states during brownout. In shutdown mode, pulling ERROR to VO ensures correct logic level. The LP2957AISX/NOPB ERROR signal is used for µP watchdog triggering or system-level fault logging.
Can LP2957AISX/NOPB be used with reverse battery connection, and how is protection implemented?
Yes, LP2957AISX/NOPB includes internal reverse-battery protection on the IN pin, allowing it to withstand −20 V input without damage. This is achieved via an integrated protection diode-eliminating the need for an external series Schottky diode and its associated forward voltage drop and power loss. However, tying SD directly to VIN sacrifices this protection; a pull-up resistor to VIN must be used if reverse-battery immunity is required while using shutdown functionality.
What is the maximum continuous output current supported by LP2957AISX/NOPB, and what limits it?
LP2957AISX/NOPB is specified to deliver 250 mA continuously under proper thermal conditions. This limit is enforced by internal current limiting (500–530 mA typical short-circuit current) and thermal shutdown (TJ > +125°C). Sustained 250 mA operation requires adequate PCB copper area (≥1.6 in²) for the DDPAK/TO-263 package to maintain θJA ≤32°C/W. Without heatsinking, power dissipation above ~1.2 W risks thermal foldback. The LP2957AISX/NOPB datasheet confirms 250 mA as the ensured output current rating.
LP2957AISX/NOPB Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- TO-263-6, D2PAK (5 Leads + Tab), TO-263BA
- Packaging:
- Tape & Reel (TR)
- Product Status:
- Active
- Output Configuration:
- Positive
- Output Type:
- Fixed
- Number of Regulators:
- 1
- Voltage - Input (Max):
- 30V
- Voltage - Output (Min/Fixed):
- 5V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 0.8V @ 250mA
- Current - Output:
- 250mA
- Current - Quiescent (Iq):
- 200 µA
- Current - Supply (Max):
- 33 mA
- PSRR:
- -
- Control Features:
- Enable
- Protection Features:
- Over Current, Over Temperature, Reverse Polarity
- Operating Temperature:
- -40°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Surface Mount
- Supplier Device Package:
- TO-263 (DDPAK-5)
LP2957AISX/NOPB FAQ
1.How can I place an order for LP2957AISX/NOPB through Aetrix?
Please submit a Request for Quotation (RFQ) for LP2957AISX/NOPB 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 LP2957AISX/NOPB reliable?
The price and inventory of LP2957AISX/NOPB are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LP2957AISX/NOPB is usually 5 days.
3.What payment methods are accepted for LP2957AISX/NOPB?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LP2957AISX/NOPB transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LP2957AISX/NOPB?
LP2957AISX/NOPB orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LP2957AISX/NOPB 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 LP2957AISX/NOPB?
For technical support, including LP2957AISX/NOPB datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LP2957AISX/NOPB requirements.
6.How does Aetrix verify that LP2957AISX/NOPB is sourced from the original manufacturer or authorized distributors?
All LP2957AISX/NOPB 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 LP2957AISX/NOPB meets industry standards.
7.What is the process for return or replacement of LP2957AISX/NOPB?
All LP2957AISX/NOPB units undergo pre-shipment inspection (PSI). If there is an issue with LP2957AISX/NOPB, 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 LP2957AISX/NOPB part is unused and in its original packaging.
Return procedure for LP2957AISX/NOPB:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LP2957AISX/NOPB Tags
-
MIC5504-1.8YM5-TR
Microchip Technology
-
MIC5504-3.3YM5-TR
Microchip Technology
-
MIC5365-3.0YC5-TR
Microchip Technology
-
MIC5365-1.8YC5-TR
Microchip Technology
-
MIC5365-2.5YC5-TR
Microchip Technology
-
MIC5365-3.3YC5-TR
Microchip Technology
-
MIC5365-3.3YD5-TR
Microchip Technology
-
MIC5317-3.3YM5-TR
Microchip Technology
-
TLV1117LV33DCYR
Texas Instruments
-
MIC5317-3.3YMT-TZ
Microchip Technology
-
MIC5528-3.3YMT-TR
Microchip Technology
-
TLV75801PDRVR
Texas Instruments
Tech Hub
A D latch stores one bit while Enable controls when data can pass. This reference covers gate-level operation, truth tables, transparency, setup and hold timing, LE versus OE, common ICs and practical …
An SR latch stores one bit through cross-coupled feedback. This engineering reference covers NOR and NAND implementations, truth tables, forbidden-state recovery, gated operation, switch debouncing, fa…
Latch circuits retain one bit through feedback. This technical reference covers SR and D latches, truth tables, transparency, timing limits, latch-versus-flip-flop behavior, applications and common log…
An engineering guide to LED driver operation, constant-current and constant-voltage outputs, linear and switching topologies, dimming, IC selection, calculations, replacement compatibility, and fault c…
Operational amplifier guide covering op amp basics, feedback, ideal vs real op amps, common configurations, buffer circuits, offset, bias current, gain-bandwidth, slew rate, rail-to-rail limits and sel…
Jumper cables guide covering safe connection order, red and black clamp placement, final ground connection, cable gauge, length, clamp quality, copper vs CCA cables, jump starter comparison and battery…
LDO regulator guide covering low dropout voltage, power dissipation, thermal design, PSRR, output noise, capacitor stability, adjustable LDO circuits, LDO vs buck converter and datasheet selection chec…
Conditional Access Module guide covering CAM meaning, CI/CI+ interface, smart card authorization, DVB security workflow, TV and set-top box compatibility, internal electronics, ESD protection, connecto…
Guide to electronic component obsolescence covering EOL risk, PCN/PDN notices, last-time buy planning, replacement options, form-fit-function validation, counterfeit risk and BOM lifecycle management.
18650 battery guide covering lithium-ion cell basics, 3.6V/3.7V voltage, 4.2V charging, mAh and Wh capacity, protected cells, chargers, BMS, series-parallel packs, holders, welding and sourcing checks.…
