Review 025: LM117T 3.3V Low Dropout Voltage Regulator Review

Product specifications

General
Manufacturer: National Semiconductors
Type: Voltage Regulator
Architecture: For all electronics
Package/Case: TO-220
RoHS: Compliant
Regulator Topology: Positive fixed
Regulator Type: Linear
Main Feature: Low Dropout, Current Limiting & Thermal Protection
Ripple Regulation (if ripple frequency is 120 Hz, input/output voltage is 3 volts and ripple voltage is 1 volt peak-to-peak): 60 - 75 dB
Temperature Stability: 0.5%
Long Term Stability (if ambient temperature is 125°C for 1000 hours): 0.3%
RMS Output Noise (% of output voltage if the frequency is ≥ 10 Hz but ≤ 10 KHz): 0.003%
Thermal Resistance (Junction-to-Case): 3°C/W
Thermal Resistance (Junction-to-Ambient with no air flow): 79°C/W
Thermal Regulation (if ambient temperature is 25°C with a 30ms pulse): 0.01%/W - 0.1%/W
Junction Temperature: 0°C - 150°C
Storage Temperature: -65°C - 150°C
Lead Temperature: 260°C for 10 seconds
ESD Tolerance: 2000 volts

Power
Maximum Input Voltage (input voltage to ground): 20 volts
Power Dissipation: Internally limited
Output Voltage (if junction temperature is 25°C, output current is ≥ 0 mA but ≤ 800 mA and input voltage is ≥ 4.75 volts but ≤ 10 volts): 3.235 - 3.365 volts
Line Regulation (if output current is 0 mA and input voltage is ≥ 4.75 volts but ≤ 15 volts): 1 - 6 mV
Load Regulation (if input voltage is 4.75 volts and output current is ≥ 0 mA but ≤ 800 mA: 1 - 10 mV
Dropout Voltage (if output current is 100 mA): 1.10 - 1.20 volts
Dropout Voltage (if output current is 500 mA): 1.15 - 1.25 volts
Dropout Voltage (if output current is 800 mA): 1.20 - 1.30 volts
Current Limit (if input/output voltage is 5 volts and junction temperature is 25°C): 800 - 1500 mA
Quiescent Current (if input voltage is ≤ 15 volts): 5 - 10 mA
Weight and Size Dimensions
Product Weight: 2g
Product Size (L x W x H): 9.7 x 4.2 x 28.5 mm
Tab Dimensions (L x W x H): 9.7 x 1.0 x 6.3 mm
Case Dimensions (L x W x H): 9.7 x 4.2 x 8.0 mm
Lead Dimensions (L x W): 0.5 x 0.1 x 13.6 mm

product review

pinout

To start off with, this simple yet efficient and powerful voltage regulator provides a whole lot of functionality to a project or circuit due to the fact that it:
1. Has a low voltage dropout (± 1 volt on different amperages).
2. Is small in regards to its physical dimensions for breadboard circuits or PCB projects.
3. Can be used with a high temperature of 150°C for projects involving high current or direct heat.
4. Has a thermal tab for an external heatsink to be mounted to the regulator, if necessary.
5. Has a fairly simple pinout (pinout to the right).

Left leg (case facing me) - GND
Middle leg (case facing me) - Output voltage
Right left (case facing me) - Input voltage