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I do not understand the NE556 circuit depicted in this data sheet:
https://cdn-reichelt.de/documents/datenblatt/A200/NE-SA-SE556-TI.pdf
on page 6 in figure 1.

NE556 datasheet - figure 1, circuit for astable operation

More specifically I do not understand why they loop 'Out' back to 'Vcc'. I also don't understand how 'RL'´s resistance will influence the circuit.

I am sorry if this question is trivial in any way. I just don't know where to ask apart from here. Thanks

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    \$\begingroup\$ "RL" is the "load resistance" which represents the circuit you are attaching the 555 timer to. \$\endgroup\$ – Ron Beyer Aug 14 at 20:32
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    \$\begingroup\$ That schematic really should show a connection between the Vcc node and the Vcc pin. \$\endgroup\$ – Hearth Aug 14 at 20:48
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    \$\begingroup\$ If 'Vcc' was actually connected to a voltage source I guess attaching the load in-between 'Vcc' and 'Out' rather than 'Ground' and 'Out' would just invert the signal. But 'Vcc' is exclusively attached to 'Out', isn't it? \$\endgroup\$ – Lukas Schmale Aug 14 at 20:49
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The "Vcc" terminal of the IC should be connected to the Vcc(5-15V) point at the upper left, as shown in Figure 2 on the datasheet.

Since the 556 output can source or sink current, RL is not needed (but is perhaps shown to suggest how you could connect an external load.)

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Connecting RL between VCC and Output pin improves the output high voltage parameter VOH .
Reference from TI datasheet below
About 1kOhms is mentioned in the datasheet for the specifications.

Choose RA and C so that RA× C > [maximum normal input high time]. RL improves VOH, but it is not required for TTL compatibility.

VCC should definitely be connected to the 5V - 15V source which is missing in the circuit diagram.

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