LM340

Part: LM340 / LM340A / LM7805 / LM7812 / LM7815 — Texas Instruments

Type: Fixed Positive Linear Voltage Regulator (3-terminal)

Description: Wide-input (up to 35 V), 1.5 A fixed-output positive linear regulators in 5 V, 12 V and 15 V options with internal current limiting, thermal shutdown and SOA protection.

Operating Conditions:

• Supply voltage: up to 35 V DC input (see abs-max); input must be at least 7.5 V for the 5 V version, 14.6 V for the 12 V version and 17.7 V for the 15 V version to maintain line regulation
• Operating temperature: 0 to 125 °C (TA, LM340/LM340A)
• Output current: up to 1.5 A (specified up to 1 A over the full tolerance and temperature range)

Absolute Maximum Ratings:

• Max DC input voltage: 35 V
• Max junction temperature: 150 °C
• Storage temperature: -65 to 150 °C
• Lead temperature (soldering): 300 °C for the TO-3 package; 230 °C at 1.6 mm from case for 10 s
• Internal power dissipation: internally limited
• ESD (HBM): ±2000 V

Key Specs:

• LM340A output voltage (5 V, TJ = 25 °C): 4.9–5.1 V; 4.8–5.2 V over load, line and temperature
• LM340/LM7805 output voltage (TJ = 25 °C, 5 mA ≤ IO ≤ 1 A): 4.8–5.2 V
• LM7812 output voltage (TJ = 25 °C): 11.5–12.5 V; LM7815: 14.4–15.6 V
• Dropout voltage: 2 V typ (IO = 1 A, TJ = 25 °C)
• LM340A line regulation (7.5 V ≤ VIN ≤ 20 V, TJ = 25 °C): 3 mV typ, 10 mV max
• LM340A load regulation (5 mA ≤ IO ≤ 1.5 A, TJ = 25 °C): 10 mV typ, 25 mV max
• Quiescent current: 6 mA max (LM340A, TJ = 25 °C); 8 mA max (LM340/LM7805/7812/7815, IO ≤ 1 A)
• Ripple rejection (120 Hz, TJ = 25 °C, IO ≤ 1 A): 80 dB typ (LM7805), 72 dB typ (LM7812), 70 dB typ (LM7815)
• Output noise (10 Hz–100 kHz): 40 μV typ (5 V), 75 μV (12 V), 90 μV (15 V)
• Short-circuit current (TJ = 25 °C): 2.1 A typ (5 V), 1.5 A (12 V), 1.2 A (15 V); peak output current 2.4 A typ

Features:

• Output current up to 1.5 A
• Fixed 5 V, 12 V and 15 V options
• ±2% output tolerance at TJ = 25 °C (LM340A)
• Line regulation 0.01%/V at 1 A load (LM340A)
• Load regulation 0.3%/A (LM340A)
• Internal thermal overload, short-circuit and SOA protection
• Available in SOT-223 package
• Output capacitor not required for stability

Applications:

• Industrial power supplies
• SMPS post regulation
• HVAC systems
• AC inverters
• Test and measurement equipment
• Brushed and brushless DC motor drivers
• Solar energy string inverters

Package:

• DDPAK/TO-263 (3 pins) — 10.18 mm × 8.41 mm
• SOT-223 (4 pins) — 6.50 mm × 3.50 mm
• TO-220 (3 pins) — 14.986 mm × 10.16 mm
• TO-3 (2 pins) — 38.94 mm × 25.40 mm

• 1 · Output Current up to 1.5 A
• Available in Fixed 5-V, 12-V, and 15-V Options
• Output Voltage Tolerances of ±2% at TJ = 25°C (LM340A)
• Line Regulation of 0.01% / V of at 1-A Load (LM340A)
• Load Regulation of 0.3% / A (LM340A)
• Internal Thermal Overload, Short-Circuit and SOA Protection
• Available in Space-Saving SOT-223 Package
• Output Capacitance Not Required for Stability

• Industrial Power Supplies
• SMPS Post Regulation
• HVAC Systems
• AC Inventors
• Test and Measurement Equipment
• Brushed and Brushless DC Motor Drivers
• Solar Energy String Invertors

SPACE

IOUT = 1 A, 0°C ≤ TJ ≤ 125°C (LM340A) unless otherwise specified (1)

over operating free-air temperature range (unless otherwise noted) (1)(2)

over operating free-air temperature range (unless otherwise noted)

The LM340x and LM7805 series is designed with thermal protection, output short-circuit protection, and output transistor safe area protection. However, as with any IC regulator, it becomes necessary to take precautions to assure that the regulator is not inadvertently damaged. The following describes possible misapplications and methods to prevent damage to the regulator.