# Regular Meeting (2022.1.3)

* About PMW-Circuit
* About zybo-z7
* Ensure /init file

## About PMW-Circuit

* [Request FAE to recommand PWM-IC for our purpose](https://e2e.ti.com/support/clock-timing-group/clock-and-timing/f/clock-timing-forum/1065064/product-suggestion-high-speed-square-wave-generator-with-variable-duty-cycle/3941531#3941531)

### Way1 (Recommend)
* [TI-EXAMPLE](https://www.ti.com/lit/ug/slau508/slau508.pdf)
* BOM
* OPA:
* Using example
* BW ~= 50MHz
* Buy others(research)
* Yu-Tang buyed one
* Hard to solder
* Not only transboard too expensive, but also we have not experiment (maybe damage ic)
* [TLV3502](https://www.ti.com/lit/ds/sbos507a/sbos507a.pdf?ts=1641146439267&ref_url=https%253A%252F%252Fwww.google.com%252F): comparator
* Good package for solder
* Rising/falling time ~ 1.5ns
* 1% passive-component(Resistor)
* https://www.ti.com/lit/pdf/tidr208
* [REF3325](https://www.ti.com/lit/ds/symlink/ref3325.pdf?ts=1641147942321&ref_url=https%253A%252F%252Fwww.ti.com%252Fproduct%252FREF3325): Reference Voltage
* [Voltage regulator vs. voltage reference](https://electronics.stackexchange.com/questions/221312/voltage-regulator-vs-voltage-reference)
* [Precision vs Accuracy](https://i.imgur.com/DmtCYqw.png)
* Error AMP seems necessary for our case
* I'm not sure that:
* Does hole board and pin componet can impact perfromance?
### Way2
* [SG3525a](https://www.onsemi.com/pdf/datasheet/sg3525a-d.pdf) seems to can be tried first
* [Example circuit](https://www.researchgate.net/figure/40-kHz-PWM-signal-generation-circuit-using-SG3525_fig2_328131786)
* Evaluate @400kHz square wave (see above paper)
* Change duty cicle with [precise potentimeter](https://shopee.tw/%E3%80%90%E7%A5%A5%E6%98%8C%E9%9B%BB%E5%AD%90%E3%80%91100%CE%A9~50K-%E5%8F%AF%E8%AE%8A%E9%9B%BB%E9%98%BB-%E7%B2%BE%E5%AF%86%E5%A4%9A%E5%9C%88%E7%B7%9A%E7%B9%9E%E9%9B%BB%E4%BD%8D%E5%99%A8-%E7%B2%BE%E5%AF%86%E9%9B%BB%E9%98%BB-3590S-2-502-(1%E5%85%A5)-i.27742636.7338380711)

### Common Bom
* [Precise potentimeter](https://shopee.tw/%E3%80%90%E7%A5%A5%E6%98%8C%E9%9B%BB%E5%AD%90%E3%80%91100%CE%A9~50K-%E5%8F%AF%E8%AE%8A%E9%9B%BB%E9%98%BB-%E7%B2%BE%E5%AF%86%E5%A4%9A%E5%9C%88%E7%B7%9A%E7%B9%9E%E9%9B%BB%E4%BD%8D%E5%99%A8-%E7%B2%BE%E5%AF%86%E9%9B%BB%E9%98%BB-3590S-2-502-(1%E5%85%A5)-i.27742636.7338380711) \*5~10 (maybe different R-value)
* 祥昌 in stock, near 光華
* [Driver Transistor R-time < 10ns ](https://shopee.tw/1%E5%80%8B-PHILIPS-BSX20-NPN-0.36W-15V-0.5A-%E9%9B%BB%E6%99%B6%E9%AB%94-i.22621384.9981790532)\*10~20
* in stock, near 光華
* Cable with Crocodile clip \*5

### Bandwidth of output side

###### tags: `Regular Meeting` `DeWei`