My Inquiry
My Account
Texas Instruments LM2940CT-9.0
- Part No.:
- LM2940CT-9.0
- Manufacturer:
- Texas Instruments
- Package:
- TO-220-3
- Datasheet:
-
LM2940CT-9.0.pdf
- Description:
- IC REG LINEAR 9V 1A TO220-3
- Quantity:
- Payment:
- Shipping:
Inventory:1,189
Please send an inquiry. Send us your inquiry, and we will respond immediately.
Product details
Overview
LM2940CT-9.0 from Texas Instruments is a 1A low-dropout linear voltage regulator in TO-220 package, delivering a fixed 9.0V output with typical dropout voltage of 0.5V at 1A load, reverse battery protection, and internal short-circuit/thermal overload protection. It is designed for automotive and industrial power rails where stable 9V supply is required under wide input transients.
For engineers reviewing the LM2940CT-9.0 datasheet, LM2940CT-9.0 pinout, LM2940CT-9.0 application, or LM2940CT-9.0 equivalent, key selection criteria include dropout performance at full load, reverse polarity tolerance (−30V DC), thermal shutdown behavior, and minimum 22 μF output capacitor stability requirement.
Technical Context
The LM2940CT-9.0 uses a PNP pass transistor architecture enabling low dropout operation while maintaining regulation down to VIN − VOUT = 0.5V. Its quiescent current reduction circuit lowers ground current to 30 mA at 5V differential, rising only when entering dropout (VIN − VOUT ≤ 3V).
It integrates reverse-battery protection, mirror-image insertion immunity, and automatic shutdown during load-dump transients exceeding 26V. The device operates across 0°C to 125°C ambient temperature and requires no external components beyond input/output capacitors for basic functionality.
Key Specifications
| Parameter | Value and Actual Design Meaning |
|---|---|
| Output Voltage | Fixed 9.0V ±2.7% (8.73V–9.27V) over full temperature and load range - ensures compatibility with 9V logic and analog subsystems. |
| Dropout Voltage | 0.5V typical @ 1A - enables regulation from 9.5V input, critical for automotive cold-crank (≥6.5V) and battery-depleted scenarios. |
| Max Input Voltage | 26V continuous - withstands ISO 7637-2 pulse 5a (load dump) up to 100 ms without shutdown or damage. |
| Reverse Polarity | Withstands −30V DC input - protects against accidental battery reversal in vehicle service environments. |
| Output Current | 1A guaranteed minimum - supports high-current peripherals like solenoids, sensors, and CAN transceivers. |
| Quiescent Current | 30 mA max @ VIN = VOUT + 5V, IO = 1A - balances efficiency and transient response in always-on systems. |
| Stability Capacitor | 22 μF minimum output capacitance with controlled ESR - prevents oscillation; aluminum/tantalum hybrid recommended for −40°C operation. |
Pinout & Package
LM2940CT-9.0 is housed in a 3-pin TO-220 (NDE) plastic package with exposed tab electrically connected to GND. Thermal resistance θJA = 60°C/W (no heatsink); θJC = 4°C/W. Mounting tab must be soldered to PCB ground plane for thermal management.
| Pin | Circuit Role | Design Meaning |
|---|---|---|
| 1 | Input (VIN) | Unregulated DC input; accepts 9.5V–26V; must include ≥10 μF input capacitor near pin. |
| 2 | Ground (GND) | Power and control ground reference; tied internally to metal tab - requires low-impedance PCB connection. |
| 3 | Output (VOUT) | Regulated 9.0V output; requires ≥22 μF output capacitor with ESR between 0.1–10 Ω for stability. |
Key Features
| Feature | Design Value |
|---|---|
| Low Dropout Operation | 0.5V typical at 1A enables use with marginal input sources (e.g., 12V battery at 10.5V during cranking). |
| Reverse Battery Protection | Survives −30V DC input - eliminates need for external series diode in automotive harnesses. |
| Mirror-Image Insertion Immunity | No damage if installed backward - simplifies assembly and field replacement in high-volume OEM lines. |
| Load-Dump Transient Shutdown | Auto-shutdown during >26V input spikes (e.g., alternator load dump) - prevents downstream component stress. |
| Thermal & Short-Circuit Protection | Internal foldback current limiting and thermal shutdown at ~150°C - ensures safe failure mode under fault conditions. |
Applications
| Automotive Body Control Module (BCM) | Industrial PLC I/O Power Rail |
|---|---|
|
Use Scenario: Powers microcontroller, CAN transceiver, and sensor interface circuitry in door module with 12V battery input subject to cold-crank and load-dump events. IC Role / Device Role / Timing Role: Primary 9V LDO supplying regulated bias to safety-critical logic and communication ICs. Use Value: Reverse polarity and load-dump immunity eliminate external protection components, reducing BOM count and board area by 30%. |
Use Scenario: Provides isolated 9V rail for analog input conditioning and relay driver stages in DIN-rail mounted programmable logic controller. IC Role / Device Role / Timing Role: Local point-of-load regulator decoupling noisy 24V industrial bus for precision ADC reference and op-amp bias. Use Value: 0.5V dropout allows stable 9V output even when 24V supply sags to 12V during motor startup transients. |
| Telematics GPS/Cellular Modem | Off-Highway Equipment Display |
|
Use Scenario: Supplies 9V to LTE modem and GNSS receiver in vehicle telematics unit operating across −40°C to +85°C ambient. IC Role / Device Role / Timing Role: Main system regulator ensuring clean, low-noise power for RF-sensitive receivers and baseband processors. Use Value: 270 μVrms output noise and 64 dB ripple rejection at 120 Hz maintain signal integrity in GPS L1 band reception. |
Use Scenario: Powers ruggedized LCD display and touch controller in construction equipment cab exposed to vibration, dust, and wide temperature swings. IC Role / Device Role / Timing Role: Robust local regulator delivering fault-tolerant 9V to display backlight drivers and MCU peripherals. Use Value: Internal short-circuit and thermal protection prevent field failures due to connector shorts or condensation-induced leakage paths. |
Equivalent & Alternatives
The following parts are listed as comparable options for similar LDO regulator applications.
| Alternative Part | Technical Difference | Application Difference | Selection Advice |
|---|---|---|---|
| LM2940CS-9.0/NOPB | Same electrical specs, but in DDPAK/TO-263 (KTT) surface-mount package with θJA = 80°C/W and integrated thermal pad. | Better suited for automated SMT assembly and higher-power density layouts; requires PCB copper pour and thermal vias. | Select for space-constrained PCBs needing improved thermal performance over TO-220, provided reflow profile supports KTT package. |
| TPS7A4700RGWR | Ultra-low-noise (4 μVrms) 1A LDO with adjustable output; dropout 300 mV @ 1A; no reverse-battery protection. | Targeted at precision analog and RF applications; lacks automotive-grade fault protections built into LM2940CT-9.0. | Choose only when ultra-low noise is mandatory and reverse-polarity/load-dump events are mitigated externally. |
Compared with LM2940CS-9.0/NOPB, the LM2940CT-9.0 offers simpler through-hole assembly and lower thermal resistance in free-air, while TPS7A4700RGWR trades automotive robustness for superior noise performance - making LM2940CT-9.0 the default choice for cost-sensitive, high-reliability vehicular power rails.
Availability
LM2940CT-9.0 is available at Aetrix Electronics and suitable for automotive body electronics, industrial PLCs, and off-highway display systems requiring stable component supply with long lifecycle support and RoHS-compliant packaging.
Supply support for LM2940CT-9.0 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 power management ICs, with decades of automotive qualification experience and AEC-Q100-compliant product lines.
The LM2940 series was engineered specifically for harsh automotive environments - delivering reliable 1A LDO regulation with integrated reverse-battery, load-dump, and mirror-insertion protection without external components.
FAQ
What is the minimum input voltage required for LM2940CT-9.0 to maintain regulation?
The LM2940CT-9.0 requires VIN ≥ VOUT + dropout voltage. With a typical dropout of 0.5V at 1A, the minimum functional input is 9.5V. At light loads (100 mA), dropout drops to 110 mV, allowing operation down to ~9.11V. Below this, output voltage collapses linearly with input.
Does LM2940CT-9.0 require an input capacitor, and what value is recommended?
Yes - a minimum 10 μF aluminum or tantalum input capacitor placed within 1 cm of the LM2940CT-9.0 input pin is required to suppress high-frequency noise and prevent instability during line transients. Ceramic capacitors alone are insufficient due to low ESR; hybrid (aluminum + ceramic) is preferred.
Can LM2940CT-9.0 be used in applications below 0°C ambient temperature?
No - the LM2940CT-9.0 is rated for 0°C to 125°C ambient operation. For sub-zero environments (e.g., −40°C), select the LM2940IMP-9.0/NOPB in SOT-223 package, which is specified from −40°C to +85°C and features identical electrical performance with enhanced low-temp capacitor compatibility.
What is the purpose of the "P+" marking on the LM2940CT-9.0 package?
The "P+" marking indicates TI's Enhanced Product (P+) qualification level - meaning the LM2940CT-9.0 undergoes additional screening including burn-in, extended temperature testing, and lot traceability per TI's enhanced reliability program, commonly required for industrial and automotive Tier-1 suppliers.
How does the quiescent current of LM2940CT-9.0 behave under varying input-output differentials?
The LM2940CT-9.0 features a quiescent current reduction circuit that holds IQ at ~10 mA when VIN − VOUT > 3V (e.g., 15V input → 30 mA IQ). When differential drops ≤3V (entering dropout), IQ rises to ~45 mA to sustain regulation - a deliberate trade-off to preserve output accuracy under marginal input conditions.
LM2940CT-9.0 Specifications
- Product attributes
- Attribute value
- Manufacturer:
- Texas Instruments
- Series:
- -
- Package/Case:
- TO-220-3
- Packaging:
- Tube
- Product Status:
- Obsolete
- Output Configuration:
- Positive
- Output Type:
- Fixed
- Number of Regulators:
- 1
- Voltage - Input (Max):
- 26V
- Voltage - Output (Min/Fixed):
- 9V
- Voltage - Output (Max):
- -
- Voltage Dropout (Max):
- 0.8V @ 1A
- Current - Output:
- 1A
- Current - Quiescent (Iq):
- 10 mA
- Current - Supply (Max):
- 15 mA
- PSRR:
- 64dB (120Hz)
- Control Features:
- -
- Protection Features:
- Over Current, Over Temperature, Reverse Polarity, Short Circuit
- Operating Temperature:
- 0°C ~ 125°C
- Grade:
- -
- Qualification:
- -
- Mounting Type:
- Through Hole
- Supplier Device Package:
- TO-220-3
LM2940CT-9.0 FAQ
1.How can I place an order for LM2940CT-9.0 through Aetrix?
Please submit a Request for Quotation (RFQ) for LM2940CT-9.0 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 LM2940CT-9.0 reliable?
The price and inventory of LM2940CT-9.0 are updated periodically and may fluctuate due to market conditions. Stock and pricing data are typically refreshed every 24 hours. Quotation validity for LM2940CT-9.0 is usually 5 days.
3.What payment methods are accepted for LM2940CT-9.0?
We accept Wire Transfer, PayPal, Credit Card, Western Union, MoneyGram, and Escrow for LM2940CT-9.0 transactions.
Note: Certain payment methods may incur a processing fee.
4.How is shipping managed for LM2940CT-9.0?
LM2940CT-9.0 orders can be shipped via leading logistics carriers, including DHL, UPS, FedEx, TNT, or Registered Mail.
Once your LM2940CT-9.0 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 LM2940CT-9.0?
For technical support, including LM2940CT-9.0 datasheets, pinout diagrams, or application guidance, please contact our engineering support team. They can provide detailed documentation and assistance for your LM2940CT-9.0 requirements.
6.How does Aetrix verify that LM2940CT-9.0 is sourced from the original manufacturer or authorized distributors?
All LM2940CT-9.0 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 LM2940CT-9.0 meets industry standards.
7.What is the process for return or replacement of LM2940CT-9.0?
All LM2940CT-9.0 units undergo pre-shipment inspection (PSI). If there is an issue with LM2940CT-9.0, 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 LM2940CT-9.0 part is unused and in its original packaging.
Return procedure for LM2940CT-9.0:
1.Submit a request within 90 days.
2.Obtain a Return Material Authorization (RMA) from Aetrix.
LM2940CT-9.0 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.…
