校准座主要测试各个pin脚是否正常提供的电压和在带载(75ma的负载)情况下电压是否在范围呢,要是自检座测试都通过了,这个测试不正常就说明零件有老化,需要更换相应驱动芯片了
主要检测以下项目
VPUmin = 1.80V (allowed voltage interval: from 1.44V to 2.30V *)
VPUmax = 5.00V (allowed voltage interval: from 4.00V to 5.50V *)
TTL H levels test:
VHmin = 1.80V (allowed voltage interval: from 1.44V to 2.30V)
VHmax = 5.00V (allowed voltage interval: from 4.00V to 5.50V)
VCCP voltage levels test:
VCCPmin = 1.80V (allowed voltage interval: from 1.71V to 1.89V **)
VCCPnom = 5.00V (allowed voltage interval: from 4.90V to 5.10V **)
VPP1 voltage levels test:
VPP1min = 1.80V (allowed voltage interval: from 1.64V to 1.91V **)
VPP1nom = 17.00V (allowed voltage interval: from 16.66V to 17.34V **)
VPP1max = 26.00V (allowed voltage interval: from 24.70V to 27.30V **)
VPP2 voltage levels test:
VPP2min = 1.80V (allowed voltage interval: from 1.64V to 1.91V **)
VPP2nom = 17.00V (allowed voltage interval: from 16.66V to 17.34V **)
VPP2max = 26.00V (allowed voltage interval: from 24.70V to 27.30V **)
Internal frequency test:
Frequency 25MHz = pass
Frequency 100kHz = pass
这些项目上只要通过了自检座的,一般非带载测试电压都没问题的,隐性问题主要就是在带载(默认负载电流75ma)时出现
主要体现是带载时电压过低或者电压上上下下跳动或者电压慢慢降,也有表现比较少的电压会上升一点点,而最主要出问题的就是VCCP,vpp2
就是说带载能力差了
带载差的话就可能遇上芯片耗电大的烧写电压不正常导致问题
官方建议是75ma带载能力,我这都还没到呢,60多70ma这样,电压都跳了
烧录时电流不够会导致烧录深度不够,一般烧录芯片都有个最基本的烧录电流
低于这个电流就有可能当时烧录没问题了,但是用了段时间可能固件出错
一般出现这类问题主要是经常烧录某类芯片导致用到的那些脚相关的零件老化或者相关的电源供电模块性能下降,一般后者的话会出现整个功能性问题,例如vccp,基本就是全灭的
有些表现在某几个脚的电压降的很厉害,这类一般都是驱动相关pin脚的零件老化,可以针对更换
下面是日志: