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SN74LS624: Output power of the VCO ?

Part Number: SN74LS624

Hi Team,

I'm trying to figure out what's the output power of the SN74LS624 VCO.

On the datasheet it's mentioned that V_oh=3.4V typ.

does it mean that if we use it on 50ohm we will get about 14dBm of output power ?

Best regards,

Nir.

  • This device use standard LS outputs (see page 5 of the datasheet). Input and Output Characteristics of Digital Integrated Circuits at 5-V Supply Voltage (SZZA008) shows typical characteristics:

    So a load of 50 Ω would see a high-level voltage of about 1.35 V, which results in about 36 mW, which is indeed about 15 dBm.

    Please note that the characteristics are not guaranteed at high-level currents of more than 1.2 mA, and that low and high currents are not symmetrical. For most 50 Ω applications, you would want to add a driver designed for such an impedance.