78XX vs 79XX: Understanding Voltage Regulator Differences

voltage regulator
electronics
circuit design
78xx regulator
79xx regulator

This article clarifies the differences between 78XX and 79XX voltage regulators, offering a quick comparison for electronics enthusiasts.

78XX Voltage Regulator

78XX Voltage Regulator

Figure 1 (not shown here, but referenced in the original text) depicts the 78XX voltage regulator pin diagram. This particular one is manufactured by Fairchild.

Here’s a rundown of the 78XX regulator’s key features:

  • Type: 3-terminal positive voltage regulator.
  • Output Current: 1 A
  • Output Voltages: Available in various fixed voltages like 5V, 6V, 8V, 9V, 10V, 12V, 15V, 18V, and 24V.
  • Protection: Includes thermal overload protection, short circuit protection, and output transistor safe operating area protection.

79XX Voltage Regulator

79XX Voltage Regulator

Figure 1 (again, as referenced in the source) depicts the 79XX voltage regulator pin diagram. This model is manufactured by National Semiconductor.

Let’s look at what the 79XX regulator offers:

  • Type: 3-terminal negative voltage regulator.
  • Fixed Output Voltages: Typically available in -5V, -8V, -12V, and -15V.
  • Output Current: 1.5 A
  • Protection: Features thermal, short circuit, and safe area protection.
  • Ripple Rejection: High ripple rejection capability.
  • Voltage Adjustment: Allows the output voltage to be boosted above the preset value using a resistor divider.

Conclusion

In short, the primary difference is that the 78XX series is a positive voltage regulator, while the 79XX series is a negative voltage regulator.

78xx voltage regulator circuit diagram

(../../assets/78xx-voltage-regulator-circuit-diagram.jpg)

LM317 and LM7805 Linear Voltage Regulators

LM317 and LM7805 Linear Voltage Regulators

Explore the features, applications, and differences between the LM317 adjustable regulator and the LM7805 fixed voltage regulator in circuit design.

linear regulator
voltage regulator
circuit design

ECL: The Fastest Logic Family Explained

Explore why Emitter-Coupled Logic (ECL) stands out as the fastest logic family. Discover its differential signaling, current mode operation, and limited voltage swing advantages.

logic family
ecl
high speed