完善资料让更多小伙伴认识你,还能领取20积分哦, 立即完善>
我有一个PIC16F1764 CCT,我有一个外部精密电压基准提供我的ADC和DAC通过引脚连接VREF + RA1,这也是ICSP CLK。我不想在编程后或在原型过程中焊接电容器,所以阻抗需要保持在最低限度,以实现编程和正确的操作。一个愚蠢的引脚共享这样一个敏感的输入类型!我不能找到什么是最小的电阻值隔离在编程时,使用皮卡3和放大器3。可以有任何帮助,有任何其他更好的解决方案。VDD是3.0V。我有330R,但是当DAC被启用时,我可以看到电压有轻微的下降。
以上来自于百度翻译 以下为原文 I have a PIC16F1764 cct where I have an external precision voltage reference supplying my ADC & DAC via the pin connection Vref+ on RA1, which is also the ICSP CLK. I don't want to solder in capacitors after programming or during prototyping and so impedance needs to be kept to a minimum to enable both programming and correct operation. Bit of a daft pin to share such a sensitive input type! I cannot find what would be the minimum resistance value to isolate during programming using both the Pickit 3 & Promate 3. Can any one help of have any other better solution. Vdd is 3.0V. I have 330R, but I can see a slight dip in voltage when the DAC is enabled. Cheers |
|
相关推荐
6个回答
|
|
|
|
|
|
肖特基二极管将完成这项工作。来自IRR的V&U-VUT——PRGDAT1
以上来自于百度翻译 以下为原文 A Schottky diode will do the job. |<----VOUT from IRR | --------PRGDAT1 |
|
|
|
嗨,在14引脚的封装上,没有那么多引脚可供选择。也许有人已经猜到,在调试期间,您可能没有外部Vref。在我看来,至少对于一些芯片、模拟参考、AVdd、AVss和模拟外设可以位于一端,或者位于同一端。封装的rner,连同ICSP,假定在生产中是不活动的,而更嘈杂的电机控制外围设备在另一端有连接。我不知道如何安排编程工具的连接,因此这可能不实用:如果ICSP连接是5或6引脚SIP,PICkit 3样式,在ICSPCLK旁边放置一个Vref的管脚在L位置,当程序员断开连接时,在ICSPCLK和Vref管脚之间安装一个跳线。缺点可能是,如果这样做的轨迹更长,或者循环区域更多,那么可能会拾取更多的噪声。
以上来自于百度翻译 以下为原文 Hi, On a 14 pin package, there isn't that many pins to choose from. A guess may be that someone have figured that you may be able to go without external Vref during debugging. Seem to me, that at least for some chips, analog reference, AVdd, AVss and analog peripherals may be located in one end, or corner of the package, together with ICSP that presumably will be inactive in production, while more noisy motor control peripherals have connections at the other end. I do not know how you arrange connection of the programming tool, so this might not be practical: If ICSP connection is 5 or 6 pin SIP, PICkit 3 style, place a pin for Vref next to ICSPCLK in a L position, and mount a jumper between ICSPCLK and Vref pin when programmer have been disconnected. Disadvantage may be that if this make longer traces, or more loop area, it may pick up more noise. Regards, Mysil |
|
|
|
你不需要跳线。肖特基二极管将隔离电路并停止进入芯片的数据进入您使用的设备。我在PRGDATA上使用了红外器件。大约4V的下降。10BQ030.皮卡2页第31页。裁判。
以上来自于百度翻译 以下为原文 You don't need jumpers. A Schottky diode will isolate the circuit and stop data going into the chip from going into the device you are using. I've used infrared devices on prgdata. Roughly a .4v drop. 10BQ030. On page 31 of Pickit 2. ref. |
|
|
|
嗨,我不认为功率肖特基二极管的0.4V下降是无论如何可以接受的,当原始海报投资使用精确的电压基准为Vref+输入到ADC和DAC。如果基准电压是4.096V,10位ADC和10位DAC的分辨率是4毫伏。
以上来自于百度翻译 以下为原文 Hi, I don't think a 0.4 V drop in a power schottky diode will be anyway acceptable, when Original Poster invest in using a precision voltage reference for Vref+ input to ADC and DAC. Resolution of 10-bit ADC and 10-bit DAC is 4 millivolt if reference voltage is 4.096 V. Mysil |
|
|
|
谢谢你的想法,Mysil,我是相同或类似的。任何精密的电压基准都不再精确,如果它漂浮在电阻器的错误端。在这种情况下,唯一的解决办法是减少引脚到接地的电容器的潜在噪声,正如您建议的连接后编程。我茫然不知如何使用任何二极管作为解决方案。回到现在的问题-什么最小电阻值我可以摆脱使用?我知道电源3可以处理相当大的电流来拉压针高和低。精密电压基准源可以达到20mA。
以上来自于百度翻译 以下为原文 Thanks for your thoughts Mysil, I am of the same or similar in opinion. Any precision Voltage reference is no longer precision if it's left floating around at the wrong end of the resistor. In this case the only solution is to reduce potential noise with a capacitor at the pin to ground, as you suggest connected post programming. I'm at a loss to comprehend how to use any diode as solution. Back now to the question - What minimum resistor value could I get away with using? I know the Promate 3 can handle quite high currents to pull-push pins high and low. The precision voltage reference can source sink 20mA. |
|
|
|
只有小组成员才能发言,加入小组>>
5125 浏览 9 评论
1984 浏览 8 评论
1914 浏览 10 评论
请问是否能把一个ADC值转换成两个字节用来设置PWM占空比?
3148 浏览 3 评论
请问电源和晶体值之间有什么关系吗?PIC在正常条件下运行4MHz需要多少电压?
2211 浏览 5 评论
693浏览 1评论
579浏览 1评论
有偿咨询,关于MPLAB X IPE烧录PIC32MX所遇到的问题
461浏览 1评论
PIC Kit3出现目标设备ID(00000000)与预期的设备ID(02c20000)不匹配。是什么原因
598浏览 0评论
493浏览 0评论
小黑屋| 手机版| Archiver| 电子发烧友 ( 湘ICP备2023018690号 )
GMT+8, 2024-10-31 18:48 , Processed in 1.233513 second(s), Total 89, Slave 72 queries .
Powered by 电子发烧友网
© 2015 bbs.elecfans.com
关注我们的微信
下载发烧友APP
电子发烧友观察
版权所有 © 湖南华秋数字科技有限公司
电子发烧友 (电路图) 湘公网安备 43011202000918 号 电信与信息服务业务经营许可证:合字B2-20210191 工商网监 湘ICP备2023018690号