--_003_431654E85333431DBE715A030987F446ivp1_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Hi all, could I have suggestions for controlling an LM317 please In the attached diagram, the 10k pot is used to set the voltage of the HV PWM outputs What I need to add is a modulation control, which simulates the pot being rotated left and right. The pot will stay, modulation is just another mode The frequency will be 10Hz at most, sinusoidal. That's not a problem. Reading the LM317 datasheet, I see an example of a Power Follower, using an LM195, but I don't think it's going to be suitable IF I'm right assuming that ADJ can't be directly voltage-controlled (correct me if I'm wrong) then adding modulation will require either grounding the pot through a FET, so that it can be switched out, or paralleling it with some resistive element Such as - Digital pot PWM-ed 4066 switch (effective R =3D Ton/Toff) Linearly-driven FET The first two imply some additional logic, perhaps a 12F. The third seems simpler, if the FET could be is used as a resistor with R (simply) controlled between Ron and 10k ohms. If the pot is left in circuit, then R would be from Ron to Roff Any other ideas ? Joe= --_003_431654E85333431DBE715A030987F446ivp1_ Content-Type: image/gif; name="LM317_adjust.gif" Content-Description: LM317_adjust.gif Content-Disposition: attachment; filename="LM317_adjust.gif"; size=4411; creation-date="Mon, 21 Mar 2011 00:37:00 GMT"; modification-date="Mon, 21 Mar 2011 00:37:00 GMT" Content-Transfer-Encoding: base64 R0lGODlhhwJ5AYAAAAAAAP///ywAAAAAhwJ5AQAC/oyPqcvtD6OctNqLs968+w+G4kiW5omm6sq2 7gvH8kzX9o3n+s73/g8MCofEovGITCqXzKbzCY1Kp9Sq9YrNarfcrvcLDovH5LL5jE6r1+y2+w1/ ARCA+qE+X+QN+7j/DxgIZMd3F7DXZ6goyNjo+Hgyh2g4WUkHiZmpuSnRh1dYWIlHyFlqeso4GUrJ uoj6ChtrpnpYu3oLKqu7y3tFK9lq59lLXGyc5En6yQc8fPwMHS09TV1tfY2drb3N3e0do4wofpf4 bX4+nQdcq267Xo4eL6/rnGtrDz+vv0806v8PMKDAgQMvuap3iKDChaT4OXyYIZ8OhAhVSISIMaOC /ot+OGr8CNEjHJEgS84j6QalyZXfVLJxyTJmNphqaMq8mQ6TTZw8j+0887On0F1ByxQdihTV0TFL kzrV1DRM1KdUG039crWq1o46t3rtlbVL2K9k0YzdcrasWjFps7RdC5fLW19x63aFNNeuXil5q/Td C5jJ3ymDAxs2IjKZuMI2GB9+PAiCslb3xEK+bPbBunubHc/wjDl04wiKc11kiDq16oadRLsGk3hR ZwegJ8Cs/To3i9imOdMWclu3cCy8fdPSA9wC7uHMRxRPuFhz8grLm1v3MDd6jUTBr3tfkr33Z+7K v5tH4hKex3b25FR+T/q8/H4oN+NioJ0GeQrL/ub777GQbLIRJN5nCayGoEL/LfgBaxu9Z590vul3 oIEMXqjBc65IVqAM+4GDYYgXhMfMch/CUJ2IepEYmYcqvhhfCin+5iKMNuJn0XQg3sijQSjM2ABo QPboFYs/CEkkkUb6gGSSPC4JoIVO2gglD01OCWOV+jV0JZYqalnjhDt6+WWO0Dk4ZpdkYrhkise5 t6aIaIpwopTwtTBknEIlmKCPFNIRYAl56snTnCFUNOaGyAlKKJtm3inHKIo+yGijDLI4KKR+0mnp pY9mup4JmXa6Epg5hFopqfOZigOqJIyqKkis3uCqc7Gu+uhEmy766q3yzYoiopT26qt5wLpg/l+t nBb73bF4Vqbsocw2m+to0Gp2FqzTOuTsCv6Qo2Cq2zLX7bOTAirquNaVu9uuw9qqbnNvaavpudjF u+6POgaZLr7DzYujj/31Z1o4+QVMI7H+5lbOMt/ai/CB4xg3YG+WtFehhAovLFrDlLmTHn7jnHbL xbyeHPGyHIem3sfNUIfjy/lMxh47BBuK8ZkASbtyx8NKIinEKLPyMr/smVxnxon2fNmH7yjdGnIy //Yt0lC/K/HD2P2TNSHk7TcwlzgzfU49swmNtSJHU+aM1W9e7S3XftZcMy5nv022PL+IWe/QoNBt sNJhH+w3oFlpfVCBb0dIb95xcOe1wDAH/uEY4iUOfC3GQEfu+EPsoughmhQ96DHFnfOTF72eEZy4 oowL2PjpNbVLuZ1zu3uiKnjLvk3qO9wcrOXCn/zwzWPzjs3nkQgYJvIrVnsq2ss7v5fyPwpLO/V2 WS8juASKqz1c3OubM9wgxB6+T9D/yXfKPKcv/vpbYu9ug/DHNb63HIJ/f0uGt/cTTB0PdBqDV//M MZn7QGiAfbNf+6yVMAMesBsR+tuGdmc+eI0qWhALmvsm2LtFHSdpWevemTDgwffxSw8k2x8IvVE6 BUKOTzQMSIdsM72N2NBuDovaCyl4tdfVD1wmxOAK+4VC2LEubT9MHu54paFKGVFkDBxR/oaY18Em AvFy2FviBw3oRf5srDw3bKEWqZK/DHIggLDL4hnRKL/JNTCJLNyZ5P42NvS90RRphA7/mOjAPSal j+SLoMoEORRC5vCIEkRkT7JTw0imxoWNdCRO9KgmFW6rapKiX5EQYztNqmt0c6wKJpFVkPMtLHfl I8sp/bLKIOpRfUVgjB1FOa0YMiN+0oseLPGly7p9xZNWCt1YZmkbSSpzNVAhXiudUjxQ/pIKyETm qbQ2QrUQ83dWsGaMpGnJQJayVd0s5xG8Ccz9FW9OltsAOgvIF/SE84/oMgjewvJOQ0ahmvM83w4v ATa2jVOOhDEnOPupP7MJNIUdyCcj/uN5ToTSTqF2G6gYp1nQiGZinQlkWdAUajJcPqFhgesahLYj T068qYrPw0cwKngvjJrupBdEqUY3IUyYDvOfgivhLnW6RoNiDVFT1N9NN+q9IZblldRkYT2TesOl DcGhELxjS/sh1CAiDKjISilSoQgYpmYUZTP7WCj3hRerUlUWYoVoG10K16r6EIAlElgnCZrW//VS K23dpw7zow7WuImM5Cis7koXsicBFGp3PQgJbYrVKwKyqzL95i4vSzRKJfZCrBsGKzHbmXAUs5Y7 eV1twtiE7mR2YnR9ZuHOk0211bRk7khIYblJWtVgcTHL7K1vfztJvE7NqlHFFnCP/otcPuV1QB+d LTtoO1xdkRZmX2sVS2tJ2FUIMXOunSwVRXVd/oT3tZJJrnl729O3Gq4dloiuLyOL1+5StqnCteDe WofD+B6ykhGxImLGm7LYPler7X1unvoKhbV6l4rCsKAf8aszy851jPt1p37RGtS4cndXAa0tbuE7 1hCDeML8VaWJJYzdQwn2dmnrsDBpdVC3iniq2aWwSCVrRq+yNcakcRjn5OrXo5K4wjfOkKHeqWAm 8ZiSIWWfRVu0ZHiWWJwNYmdqYfG9I9XXnpB9spaFjGIin7jKonNCklVKHR9HzkRcHKmOh1zkhiJR vhjmo9zqHB9RwHiveIZyfuc8/mUjZxkZ27NigbusYH5eeMyBjki4lHDm3wF4azl1kErcNs7AqpnB Eok0naW76JjSM85vNklIBZxM7bzYqVzOWRQTXGo4i9rGYhbMIz2MRfd0eMC8/uud3QzmMDO61sO+ 8q0ruOp2UZTXm/M0JUcs4c4SMcJfpDKtIe3TBztbC4F9V+XiimmmxNqQv6DbhpUq50KauadN1pvL Fiyo5qqXq9wed7Vra+4uLnLUwa5psrdYUfIWEqQ/JcN5k7to9lqMoejO8L5tHeBel62xzdaluRY4 Mk0JJBVA9nC+n5kWgAVZq7a9NX0dUR2nNZbZDyW2tY3tXHprxNnbVjf7WjbT/k4/vNGEbq0CS0WX R6Tce2b7MaRCrl+OnJm3Fcc10IOO8o6T2sI4rK7IZOxKqFuly/xu6KPvq7Nfw3wtNF+uVK+d0Aol Zq01v8vJt+7krq+vPiMne1YFweadRxnbvHw7x7nO89rVfal3D0TeAW3vntu9soaXerHnq21h833x fse741+Op729Gjz4KzwgDi/35Wke5Fg3ZSqBHXXAu/xTmdUnxB3XdsQTUPbz1bOUz3l6NIodGbnn iuqnPvDWt1yiJ8FNW4zfRqWPdPemT/ItDX9whth89pHvW+yJ7xeSoNbPnDfzpEm1/ZFcNPHQxj46 Lj359Jvf3X/ud/nV9tHv/q//q7IWvOJZLdtPz5+P43c/jaWWMUW1f0rRf3tXfsmSawPIC+h3f+pX N2CngAtYgCk2dtGUgBG4Y+1ngO8nYNeHgZenRvanfsT1YB8IFvXHff5ngn9XV3cic5k2ghS4ghs1 evCmf96EZDOIVDXoWScUggL3Zd2ng8t1aMK3TTYYJa83hKlnHB5zNudSZg1IfksofhZzUk94QV6E g2NHhZZnhdV1T0THUxvYZ11YhS34gCwHReGngmVohrT0VKgXg2/4DNfnUB44Ztt1QhTxWNjngVSF h8qxYmZVdGwjWgqIh/K3Zy8BYeYmOQpnM7eFiHIRfZUYfTHGdI74Vk/j/l4DaId3aFzpNiKWyFAd CB/NVWBFE4EMOCkv6HpUx4VAqIEoOG2i2CHtZnUGposYyIqu5mUNV2NSKIuzeHvDJ1kbJiwWtza/ uEebpWqb5lO8BXxBWIz9RYs/OIqf5Yskt4yrKEcfp4k5x4zGKIOviGPmSI50SI2tMXqsNW/jeG// 92yUlo71qI6jJUbtSHIsdxX5pH3OYWX+dY/vV0CHZord1o+xGI/ZiHMCOZBuGGBrpml/ZVglh3nl aI/HqH9I+JAgCGtKiI6ONmjE2JH4SBwKOYxpNpLXWJK/N2NtuJF05HAtmYRugZIcqZGwSJMfdpIg mZEzmZM7+V6uNzjr/lFS62WLwpiSQemQJdhDQpk9QRJD/8ZuzpWUUxiTTdmU4QaV8bZxakc1WwmM EwiT8MiS6Wh1gehIJMNwV8dYbHiWSiZ5j0eWdOWKXYlCzGcvFhdBOgeUWGmWc0mMYKOWllRW3haQ 9XIU/hiX1giUThOYeEkbx9OQD5ReDbmYN4mNV+mYrFSYiORZ8bd2msY5cCmYELmRlbmUCcNJn0CV kvl5mjmWMqRxmQmbcDiHvvaVYpKJ7RSMtymBPtlfuTiZOgmcxMCYL0d3xnmcRCGbF8eUzYllzxmV jimd9ECdRsWc1/kKyemRp8mdzSScZ/eb4cl/40l91mmeBIiecLKd/uuJZu0JeeK1m/ApnkLokvZJ Dd6Zn+Xlm/opdNkZRwAqDfwZd9lIoKVgoGeVoAUqoCbUoNawoM0ToTkhn/NZodAwoQyaocj5oBDa oRr6oXoXoh56odpZoqinOiOKdimKe3xGoYAJoi6KbbqzjjI6ozSqeHdJngfYSSsXmTCqox+miDmK kYzVatM4pEQapKFXkxGXf3S5pPbHo+lJkFZpkRc5pVSaldXJJEWljFPxmVtqpQDympqTpH9pLK75 lg3mWJv5H43jprfXNlIqL5tSiDzkji3IWcAxQHeGamqaL+m1ifi2pwLIDaopl0eiLWNaDB60UsGA b7voc+5GnIv6/qUiiCs/h4qr1WszRIqhKqoHt1tiOKqnukya+itmdYWeioCzmQamqS+XOpRmqqrX Eaho2mo5JaSZsYiw6p6ZmoLeIW0tFoAOpldMCHeDUKQkSqarGatTxaPSWIJa+qxwyoh+SmcdZZnR ea04OTva2l1PQ4KC+q3YugbWpHykWVzeeq69ChS5+WJYyJnvCqzRynegmotiaq8h+QZIFpBWY6fv 6qjvSR+H6ZTNeq9TWrDuSjmyOn39Cq+zsG7f+a0Nq55KGawSu7DxyqItSrAB+rGBd7Eie6IDaq8Y K5P4yaH9qrJaiaPOmrImy7IxyrFN6gWgaLHX+rLlSYYoerNd/kqxI7t659qzoXal0Bm0OGsZ6NF7 Shu0R1uXNLu0UkuS0vqfXnqzVtuYj7O0HTu04KGwBuuyVEt/X8u14Nl4Xyu0RnGebJu28+h2aGu2 c1u1dWt2d6us90m3e3u2erusOMW2bWtwb9u3gcu3gMuCgju4cVuNfru1eCu5ZQu5eRu1k4u4l1u5 mBuym+u5M/u5i6u4Xsi4jcu5sTm4hCtuiQu3p+u1qTuxbpsKiEq5mdsRZxq5ofsSVQq6ulsTYzuk pwWtPdoGwBu8BkKrJnm7sMtpolqqXISq0Su9vsW8Wpa8v7q81YupsWuk/+q42ou0u/u94Ku2v8u0 5JuzVoG76uhbvOrLvewrFawLv2dot/P7r/E5vuybv51gvPY7eDrRv/4rhwAcwAJMtO1rwOl6CvtL vgzctQlsk4YLwWEbnxPssQpqwb6KwRlMwaXLwau7wR8MwhUswvErwSWcvieMwnIBFU+7wp73wpDh wJOZtTH8ki3Zhz0zw6EoHDm8MjvsKXY5OLX4lLuohQXcd125Upy4UAsVjt06qJKJbPYlmt1mhW2G pcR6m1M8qcT1ceWjr9MrxmNMxqm6xSJUUQj5UryJpzZcNmgMMhmXsJ9qae/rxk8BsXesx3vMx33s x38MyIEsyINcFwUAAAA7 --_003_431654E85333431DBE715A030987F446ivp1_ Content-Type: text/plain; name="ATT00001.txt" Content-Description: ATT00001.txt Content-Disposition: attachment; filename="ATT00001.txt"; size=208; creation-date="Mon, 21 Mar 2011 00:37:00 GMT"; modification-date="Mon, 21 Mar 2011 00:37:00 GMT" Content-Transfer-Encoding: base64 LS0gDQpodHRwOi8vd3d3LnBpY2xpc3QuY29tIFBJQy9TWCBGQVEgJiBsaXN0IGFyY2hpdmUNClZp ZXcvY2hhbmdlIHlvdXIgbWVtYmVyc2hpcCBvcHRpb25zIGF0DQpodHRwOi8vbWFpbG1hbi5taXQu ZWR1L21haWxtYW4vbGlzdGluZm8vcGljbGlzdA0K --_003_431654E85333431DBE715A030987F446ivp1_-- .