ไม่ต้องคิดมากครับนึกถึงนี่เลยครับถ้าหากต้องการ Power Supply ที่สามารถปรับแรงดันได้ตามต้องการ
LM317 Voltage
LM317 เป็นไอซีเรกูเรเตอร์รักษาระดับแรงดันตามที่ต้องการ เหมาะกับการสร้างพาวเวอร์ซัพพลายจ่ายแรงดัน 1.25-30V กระแสไม่เกิน 1.5A ( ใช้ไอซี LM317 ) วงจรง่ายๆ ไม่ยุ่งยาก แถมยังประหยัดตังค์อีกต่างหาก
ศึกษาจาก Data sheet ก่อนนะครับ
http://www.steveselectronics.com/files/LM317T_National.pdf
การต่อวงจรใช้งานก็ง่ายๆครับ
ส่วนนี่ก็เป็นวงจรป้องกันเมื่อเกิดการลัดวงจรครับ
หลายคนก็คงเกิดคำถามอีกว่าเราสามารถคำนวณหาค่า R1,R2 ได้อย่างไร
สูตร
และสุดท้าย เป็น ค่า R ที่ผ่านการคำนวณมาแล้ว เพื่อความสะดวกในการทำ Power supply สำหรับท่านครับ
1.43V R1 = 470, R2 = 68
1.47V R1 = 470, R2 = 82
1.48V R1 = 370, R2 = 68
1.51V R1 = 330, R2 = 68
1.51V R1 = 390, R2 = 82
1.52V R1 = 470, R2 = 100
1.53V R1 = 370, R2 = 82
1.56V R1 = 330, R2 = 82
1.57V R1 = 270, R2 = 68
1.57V R1 = 470, R2 = 120
1.57V R1 = 390, R2 = 100
1.59V R1 = 370, R2 = 100
1.60V R1 = 240, R2 = 68
1.63V R1 = 330, R2 = 100
1.63V R1 = 270, R2 = 82
1.64V R1 = 390, R2 = 120
1.64V R1 = 220, R2 = 68
1.65V R1 = 470, R2 = 150
1.66V R1 = 370, R2 = 120
1.68V R1 = 240, R2 = 82
1.71V R1 = 330, R2 = 120
1.71V R1 = 270, R2 = 100
1.72V R1 = 220, R2 = 82
1.72V R1 = 180, R2 = 68
1.73V R1 = 470, R2 = 180
1.73V R1 = 390, R2 = 150
1.76V R1 = 370, R2 = 150
1.77V R1 = 240, R2 = 100
1.81V R1 = 270, R2 = 120
1.82V R1 = 150, R2 = 68
1.82V R1 = 330, R2 = 150
1.82V R1 = 180, R2 = 82
1.83V R1 = 390, R2 = 180
1.84V R1 = 470, R2 = 220
1.86V R1 = 370, R2 = 180
1.88V R1 = 240, R2 = 120
1.89V R1 = 470, R2 = 240
1.93V R1 = 330, R2 = 180
1.93V R1 = 150, R2 = 82
1.94V R1 = 270, R2 = 150
1.96V R1 = 390, R2 = 220
1.97V R1 = 470, R2 = 270
1.99V R1 = 370, R2 = 220
2.02V R1 = 390, R2 = 240
2.03V R1 = 240, R2 = 150
2.06V R1 = 370, R2 = 240
2.08V R1 = 330, R2 = 220
2.10V R1 = 220, R2 = 150
2.12V R1 = 390, R2 = 270
2.13V R1 = 470, R2 = 330
2.16V R1 = 330, R2 = 240
2.16V R1 = 370, R2 = 270
2.19V R1 = 240, R2 = 180
2.23V R1 = 470, R2 = 370
2.25V R1 = 150, R2 = 120
2.27V R1 = 270, R2 = 220
2.27V R1 = 330, R2 = 270
2.29V R1 = 470, R2 = 390
2.29V R1 = 180, R2 = 150
2.31V R1 = 390, R2 = 330
2.36V R1 = 270, R2 = 240
2.37V R1 = 370, R2 = 330
2.40V R1 = 240, R2 = 220
2.44V R1 = 390, R2 = 370
2.50V R1 = 470, R2 = 470
2.57V R1 = 370, R2 = 390
2.61V R1 = 220, R2 = 240
2.65V R1 = 330, R2 = 370
2.66V R1 = 240, R2 = 270
2.73V R1 = 330, R2 = 390
2.74V R1 = 470, R2 = 560
2.75V R1 = 150, R2 = 180
2.76V R1 = 390, R2 = 470
2.78V R1 = 270, R2 = 330
2.78V R1 = 220, R2 = 270
2.84V R1 = 370, R2 = 470
2.92V R1 = 180, R2 = 240
2.96V R1 = 270, R2 = 370
2.97V R1 = 240, R2 = 330
3.03V R1 = 330, R2 = 470
3.05V R1 = 390, R2 = 560
3.06V R1 = 270, R2 = 390
3.06V R1 = 470, R2 = 680
3.08V R1 = 150, R2 = 220
3.13V R1 = 220, R2 = 330
3.14V R1 = 370, R2 = 560
3.18V R1 = 240, R2 = 370
3.25V R1 = 150, R2 = 240
3.28V R1 = 240, R2 = 390
3.35V R1 = 220, R2 = 370
3.37V R1 = 330, R2 = 560
3.43V R1 = 270, R2 = 470
3.43V R1 = 390, R2 = 680
3.43V R1 = 470, R2 = 820
3.47V R1 = 220, R2 = 390
3.50V R1 = 150, R2 = 270
3.54V R1 = 180, R2 = 330
3.55V R1 = 370, R2 = 680
3.70V R1 = 240, R2 = 470
3.82V R1 = 180, R2 = 370
3.83V R1 = 330, R2 = 680
3.84V R1 = 270, R2 = 560
3.88V R1 = 390, R2 = 820
3.91V R1 = 470, R2 = 1000
3.92V R1 = 220, R2 = 470
3.96V R1 = 180, R2 = 390
4.00V R1 = 150, R2 = 330
4.02V R1 = 370, R2 = 820
4.17V R1 = 240, R2 = 560
4.33V R1 = 150, R2 = 370
4.36V R1 = 330, R2 = 820
4.40V R1 = 270, R2 = 680
4.43V R1 = 220, R2 = 560
4.44V R1 = 470, R2 = 1200
4.46V R1 = 390, R2 = 1000
4.50V R1 = 150, R2 = 390
4.51V R1 = 180, R2 = 470
4.63V R1 = 370, R2 = 1000
4.79V R1 = 240, R2 = 680
5.04V R1 = 330, R2 = 1000
5.05V R1 = 270, R2 = 820
5.10V R1 = 390, R2 = 1200
5.11V R1 = 220, R2 = 680
5.14V R1 = 180, R2 = 560
5.17V R1 = 150, R2 = 470
5.24V R1 = 470, R2 = 1500
5.30V R1 = 370, R2 = 1200
5.52V R1 = 240, R2 = 820
5.80V R1 = 330, R2 = 1200
5.88V R1 = 270, R2 = 1000
5.91V R1 = 220, R2 = 820
5.92V R1 = 150, R2 = 560
5.97V R1 = 180, R2 = 680
6.04V R1 = 470, R2 = 1800
6.06V R1 = 390, R2 = 1500
6.32V R1 = 370, R2 = 1500
6.46V R1 = 240, R2 = 1000
6.81V R1 = 270, R2 = 1200
6.92V R1 = 150, R2 = 680
6.93V R1 = 330, R2 = 1500
6.94V R1 = 180, R2 = 820
7.02V R1 = 390, R2 = 1800
7.10V R1 = 470, R2 = 2200
7.33V R1 = 370, R2 = 1800
7.50V R1 = 240, R2 = 1200
8.07V R1 = 330, R2 = 1800
8.08V R1 = 150, R2 = 820
8.19V R1 = 270, R2 = 1500
8.30V R1 = 390, R2 = 2200
8.43V R1 = 470, R2 = 2700
8.68V R1 = 370, R2 = 2200
9.06V R1 = 240, R2 = 1500
9.58V R1 = 330, R2 = 2200
9.77V R1 = 220, R2 = 1500
9.90V R1 = 390, R2 = 2700
10.03V R1 = 470, R2 = 3300
10.37V R1 = 370, R2 = 2700
10.63V R1 = 240, R2 = 1800
11.25V R1 = 150, R2 = 1200
11.44V R1 = 270, R2 = 2200
11.48V R1 = 330, R2 = 2700
11.67V R1 = 180, R2 = 1500
11.83V R1 = 390, R2 = 3300
12.40V R1 = 370, R2 = 3300
12.71V R1 = 240, R2 = 2200
13.75V R1 = 330, R2 = 3300
15.31V R1 = 240, R2 = 2700
16.25V R1 = 150, R2 = 1800
16.53V R1 = 270, R2 = 3300
16.59V R1 = 220, R2 = 2700
18.44V R1 = 240, R2 = 3300
19.58V R1 = 150, R2 = 2200
20.00V R1 = 220, R2 = 3300
23.75V R1 = 150, R2 = 2700
24.17V R1 = 180, R2 = 3300
28.75V R1 = 150, R2 = 3300
