/technologies/555-timers/b/blog/posts/555-sawtooth-oscillatorThe ST datasheet for the 555 has this circuit for generating a linear ramp. The linearity comes from the use of a transistor to give a constant current source for the capacitor charging.As shown, it&#39;s a monostable (it&#39;s designed to generate the ramp en-USTelligent Community 12https://community.element14.com/technologies/555-timers/b/blog/posts/555-sawtooth-oscillatorTue, 07 Jun 2022 16:35:10 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:6027472e-afab-4214-b5d8-4655ed11af10scottiebabe1<p>Nice little circuit:)! It is also interesting that the RC exponential response from 1/3 VCC to 2/3 VCC is relatively linear</p> <p><img src="/resized-image/__size/1280x720/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-6027472e-afab-4214-b5d8-4655ed11af10/pastedimage1654619689341v2.png" alt=" " /></p> <p><img src="/resized-image/__size/1280x720/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-6027472e-afab-4214-b5d8-4655ed11af10/pastedimage1654619605903v1.png" alt=" " /></p><img src="https://community.element14.com/aggbug?PostID=23758&AppID=370&AppType=Weblog&ContentType=0" width="1" height="1">https://community.element14.com/technologies/555-timers/b/blog/posts/555-sawtooth-oscillatorTue, 07 Jun 2022 15:10:02 GMT93d5dcb4-84c2-446f-b2cb-99731719e767:6027472e-afab-4214-b5d8-4655ed11af10shabaz1<p>Hi Jon,</p> <p>Very useful blog post. It&#39;s a very handy circuit, also&nbsp;super-convenient for PWM.</p> <p>I used such a 555 circuit a while back to drive light-bulbs, but could probably also be used for hobby servos etc.</p> <p><img height="450" src="/resized-image/__size/1884x900/__key/commentfiles/f7d226abd59f475c9d224a79e3f0ec07-6027472e-afab-4214-b5d8-4655ed11af10/pastedimage1654614409567v1.png" width="942" alt=" " /></p> <p></p> <p></p><img src="https://community.element14.com/aggbug?PostID=23758&AppID=370&AppType=Weblog&ContentType=0" width="1" height="1">