AMB σ78 and σ79 - ultra low noise upgrade for 78xx/79xx TO-220 voltage regulators
σ78 ("sigma 78") and σ79 ("sigma 79") are DC voltage regulators designed as high-performance replacements for the common 78xx/79xx, LM340/LM320 and LM2940/LM2990 series of TO-220 3-terminal IC voltage regulators. In most cases, a direct swap is possible due to physical, heatsink and pin compatibility. σ78 is a positive voltage regulator, just like the 78xx series, whereas the σ79 is a negative voltage regulator like the 79xx. σ7x offers much lower noise and other improved performance attributes.
σ78 is based on the TPS7A4701 while σ79 is based on the TPS7A3301. Both regulators support up to 1A current, features soft-start, over-current protection and thermal shutdown. The maximum input voltage is +35V (σ78) or -35V (σ79). The output voltage range is +1.8V to +24V (σ78) or -1.8V to -24V (σ79), limited by the voltage rating of the output capacitor.
Full info here:
The σ78 and σ79 ultra low noise voltage regulators
If you have gear that uses the 78xx and/or 79xx series voltage regulator in TO-220 packages, and ultra low noise and high PSRR are important, then it is a candidate for upgrading to the σ78 /σ79. New DIY designs can also use σ78 /σ79 for an easy, high performance power supply. AMB also offers the σ25 and σ26 regulated power supply PCBs that could accommodate these regulators.
The σ78 /σ79 comes with the QFN20 voltage regulator chip pre-soldered. All you need to do is to solder 5 passive parts (three capacitors and two resistors), and the 3 pins.
To order, go to AMB audio shop.
σ78 and σ79 (as supplied with regulator chip pre-soldered):
A fully-populated σ78 (minus the pins):
Comparison of a blank and populated σ78 vs. a 78xx TO-220 regulator:
Comparison of a blank and populated σ78 vs. a US $0.25 coin:
Please read the σ78 and σ79 development thread.
σ78 ("sigma 78") and σ79 ("sigma 79") are DC voltage regulators designed as high-performance replacements for the common 78xx/79xx, LM340/LM320 and LM2940/LM2990 series of TO-220 3-terminal IC voltage regulators. In most cases, a direct swap is possible due to physical, heatsink and pin compatibility. σ78 is a positive voltage regulator, just like the 78xx series, whereas the σ79 is a negative voltage regulator like the 79xx. σ7x offers much lower noise and other improved performance attributes.
σ78 is based on the TPS7A4701 while σ79 is based on the TPS7A3301. Both regulators support up to 1A current, features soft-start, over-current protection and thermal shutdown. The maximum input voltage is +35V (σ78) or -35V (σ79). The output voltage range is +1.8V to +24V (σ78) or -1.8V to -24V (σ79), limited by the voltage rating of the output capacitor.
Full info here:
The σ78 and σ79 ultra low noise voltage regulators
If you have gear that uses the 78xx and/or 79xx series voltage regulator in TO-220 packages, and ultra low noise and high PSRR are important, then it is a candidate for upgrading to the σ78 /σ79. New DIY designs can also use σ78 /σ79 for an easy, high performance power supply. AMB also offers the σ25 and σ26 regulated power supply PCBs that could accommodate these regulators.
The σ78 /σ79 comes with the QFN20 voltage regulator chip pre-soldered. All you need to do is to solder 5 passive parts (three capacitors and two resistors), and the 3 pins.
To order, go to AMB audio shop.
σ78 and σ79 (as supplied with regulator chip pre-soldered):
A fully-populated σ78 (minus the pins):
Comparison of a blank and populated σ78 vs. a 78xx TO-220 regulator:
Comparison of a blank and populated σ78 vs. a US $0.25 coin:
Please read the σ78 and σ79 development thread.
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