感谢您的回复。
检查后、VREF 很好、芯片和 电路 跟数据表一样。
我的 DCKL 频率为9MHz、由 stm32F1 SPI 外设创建、并在72MHz 至9MHz 之间预分频8倍。
3.我 的 DDC112 范围设置为 RANGE 1 (12.5pF)。
使用测试模式的数据结果如下所示
测试条件:(1.双通道、单位为 fA; 2.积分时间为1000ms;3. RANGE1;):
CH1:13628.01 CH2:13628.11fA
CH1:13397.00 CH2:13402.51fA
CH1:13628.44 CH2:13629.47fA
CH1:13397.80 CH2:13402.84fA
CH1:13627.92 CH2:13628.95fA
CH1:13396.72 CH2:13403.21fA
CH1:13628.53 CH2:13628.15fA
CH1:13396.58 CH2:13402.18fA
CH1:13627.97 CH2:13629.75fA
CH1:13397.10 CH2:13403.12fA
CH1:13628.58 CH2:13629.90fA
CH1:13397.85 CH2:13402.22fA
CH1:13627.50 CH2:13628.86fA
CH1:13397.00 CH2:13401.33fA
CH1:13627.97 CH2:13629.24fA
CH1:13397.52 CH2:13402.93fA
测试条件:(1.双通道、单位为 PA; 2.积分时间为10ms;3. RANGE1;):
CH1:1341.40 CH2:1341.93pA
CH1:1364.61 CH2:1364.79pA
CH1:1341.51 CH2:1341.89pA
CH1:1341.47 CH2:1341.97pA
CH1:1364.60 CH2:1364.68pA
CH1:1341.44 CH2:1341.88pA
CH1:1364.60 CH2:1364.67pA
CH1:1341.49 CH2:1341.97pA
CH1:1341.52 CH2:1341.98pA
CH1:1364.53 CH2:1364.69pA
CH1:1364.58 CH2:1364.67pA
CH1:1364.59 CH2:1364.79pA
CH1:1341.46 CH2:1341.97pA
CH1:1341.42 CH2:1341.89pA
CH1:1341.46 CH2:1341.97pA
CH1:1364.54 CH2:1364.80pA
CH1:1364.62 CH2:1364.69pA
CH1:1341.42 CH2:1341.98pA
CH1:1364.65 CH2:1364.80pA
CH1:1341.44 CH2:1341.99pA
CH1:1364.63 CH2:1364.79pA
CH1:1364.58 CH2:1364.68pA
CH1:1341.48 CH2:1342.00pA
CH1:1364.62 CH2:1364.67pA
CH1:1341.39 CH2:1341.97pA
CH1:1364.61 CH2:1364.67pA
CH1:1341.44 CH2:1341.98pA
CH1:1341.38 CH2:1341.99pA
CH1:1364.56 CH2:1364.78pA
CH1:1341.42 CH2:1341.98pA
CH1:1364.58 CH2:1364.71pA
CH1:1341.46 CH2:1341.94pA
CH1:1341.45 CH2:1341.94pA
仍有磁通、为什么?
有人告诉我、这是因为50Hz 电源噪声。 但我认为 1000ms 的积分时间应该会将该噪声平均。
正在等待您的帮助。
谢谢