https://forum.arduino.cc/t/countdown-timer-and-adafruit-4-digit-7-segment-display-w-i2c-backpack/364882
I2C counter
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https://www.navimro.com/p/items/K50046407/?access_google_shopping&utm_source=google&utm_medium=cpc&utm_campaign=PLA&utm_term=K50046407&gad_source=1&gclid=Cj0KCQiA8q--BhDiARIsAP9tKI0OyUgv3SK1El03zS6HF5jowkBK-MT0MgrUrXdIuGGIN7j5BHZ8JFgaAiDLEALw_wcB
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https://onechips.rpicube.com/education/edu-10/
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https://www.robot.co.kr/product/detail.html?product_no=2695&cate_no=74&display_group=1
스테틱 구동방식
74HC595 칩 사용
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https://ko.aliexpress.com/item/1005004094987628.html?src=google&pdp_npi=4%40dis!KRW!655!506!!!!!%40!12000028015682404!ppc!!!&src=google&albch=shopping&acnt=742-864-1166&isdl=y&slnk=&plac=&mtctp=&albbt=Google_7_shopping&aff_platform=google&aff_short_key=UneMJZVf&gclsrc=aw.ds&&albagn=888888&&ds_e_adid=735403424294&ds_e_matchtype=search&ds_e_device=c&ds_e_network=g&ds_e_product_group_id=297546631617&ds_e_product_id=ko1005004094987628&ds_e_product_merchant_id=508873285&ds_e_product_country=KR&ds_e_product_language=ko&ds_e_product_channel=online&ds_e_product_store_id=&ds_url_v=2&albcp=22297473577&albag=175774105636&isSmbAutoCall=false&needSmbHouyi=false&gad_source=1&gclid=Cj0KCQiA8q--BhDiARIsAP9tKI3bdocXk03KUgVO_BUd3IqYDTM0jaW5W_r_lDUJnDYK6UuR2OSvfdoaAsquEALw_wcB
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http://www.ds-parts.co.kr/goods_detail.php?goodsIdx=2494
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https://ko.aliexpress.com/item/1005002883995270.html?src=google&pdp_npi=4%40dis!KRW!1727!1503!!!!!%40!12000022608822937!ppc!!!&src=google&albch=shopping&acnt=742-864-1166&isdl=y&slnk=&plac=&mtctp=&albbt=Google_7_shopping&aff_platform=google&aff_short_key=UneMJZVf&gclsrc=aw.ds&&albagn=888888&&ds_e_adid=735403424294&ds_e_matchtype=search&ds_e_device=c&ds_e_network=g&ds_e_product_group_id=297546631617&ds_e_product_id=ko1005002883995270&ds_e_product_merchant_id=109387757&ds_e_product_country=KR&ds_e_product_language=ko&ds_e_product_channel=online&ds_e_product_store_id=&ds_url_v=2&albcp=22297473577&albag=175774105636&isSmbAutoCall=false&needSmbHouyi=false&gad_source=1&gclid=Cj0KCQiA8q--BhDiARIsAP9tKI1XBZGLk8kr70jaNOpcxBD2pWlaqqW0dRJZc2TWa1pAUkdWirfV4ZEaAtl_EALw_wcB
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https://onechips.rpicube.com/product/big-fnd-%EC%BD%98%ED%8A%B8%EB%A1%A4%EB%B3%B4%EB%93%9C-ocs-018a/
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https://blog.naver.com/comfae/221361992394
enum 코드 있음
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https://www.devicemart.co.kr/goods/view?no=1289198&srsltid=AfmBOopuuFQGa5sCMC1ChBkbLmA-UHdZI5VnpkmE6qBbFc-P4GT8yye6
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https://forum.arduino.cc/t/need-a-simple-audio-amplifier/160669
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https://m.blog.naver.com/emperonics/222197590991
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https://www.etechnog.com/2023/09/2-digit-3-digit-and-4-digit12-pin-7.html
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https://forum.arduino.cc/t/3-digit-7seg/472368/7
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https://dronebotworkshop.com/led-displays/
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D1, D2 채널관련
https://920416.tistory.com/33?pidx=7
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https://forum.arduino.cc/t/12-volt-7-segment-display/330964
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https://www.mrelectrouino.com/2021/01/arduino-control-12v-led-with-tip120.html
TIP 달링톤의 Base는 Aruino의 신호선이 입력으로 들어간다.
이거에 따라서 Collector와 Emitter가 연결된다.
Power supply의 VCC는 Lamp의 +에 바로 연결되고
Lamp의 -는 TIP120의 collector를 거쳐서 emitter로 빠져나오고
빠져나온게 Power supply의 GND로 마무리 연결된다.
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달링톤 멀티미터로 테스트 하는 법
https://www.incbtech.com/articles/16-how-they-work/239-darlington-transistors-how-they-work-art067.html
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내블로그
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https://electronics.stackexchange.com/questions/345951/what-is-the-purpose-of-connecting-the-collector-of-an-npn-to-the-base-of-another
https://circuitglobe.com/common-base-connection-cb-configuration.html
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https://docs.sunfounder.com/projects/sf-components/en/latest/component_74hc595.html
5V 용 FND Driver
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https://www.indiamart.com/proddetail/12v-7-segment-led-display-driver-atmega8-based-21581351373.html
https://www.theengineeringprojects.com/2017/06/introduction-to-uln2003.html
https://pcb-copy.com/uln2003-pinout%EF%BC%9A-a-comprehensive-guide-on-uln2003-ic-datasheet/
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https://www.youtube.com/watch?v=jzBBAqE9wgQ
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UNL시리즈 칩
https://www.youtube.com/watch?v=7tSc-In9jpQ
왼쪽위 입력
오른쪽위 출력 >> 저항거쳐서 LED키고 GND로 빠짐
왼쪽아래 GND
오른쪽아래 외부전압
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8채널 용
1. Output current (single output): 500 mA (max)
2. High sustaining voltage output: 50 V (min)
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https://forum.arduino.cc/t/problems-with-74hc595-and-uln2003-to-drive-12v-7-segment/635719
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https://www.edaboard.com/threads/12v-5-digit-7-segment-led-driver-circuit.407612/
12V 5 digit 7 Segment LED driver circuit
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https://forum.arduino.cc/t/large-12v-7-segment-led-via-hef4543b/242006
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https://electronics.stackexchange.com/questions/56123/solution-for-driving-multiple-7-segment-led-display-from-3-volt-%C2%B5c
common Anode multi digit
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https://electronics.stackexchange.com/questions/93155/cheap-4-digit-7-segment-display-driver
common chathod
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https://forum.arduino.cc/t/two-digit-counter-with-tpic6b595n-and-12v-common-anode-7-segments-displays/306257
Two digit counter with TPIC6B595N and 12V Common Anode 7 segments displays