Читать книгу Accelerated Life Testing of One-shot Devices - Narayanaswamy Balakrishnan - Страница 17

Lau et al. (1988) considered data on 90 solder joints under three types of printed circuit boards (PCBs) at different temperatures. The lifetime was measured as the number of cycles until the solder joint failed, while the failure of a solder joint is defined as a 10% increase in measured resistance. A simplified dataset is derived from the original one and presented in Table 1.3, where two stress factors considered are temperature and a dichotomous variable indicating if the PCB type is “copper‐nickel‐tin” or not.

Table 1.2 Failure records on glass capacitors under CSALTs with two stress factors: temperature (K) and voltage (V).

Source: Zelen (1959).

Test group	Inspection time	Temperature	Voltage	Number of samples	Number of failures
1	450	443	200	8	1
2	400	453	200	8	0
3	350	443	250	8	0
4	300	453	250	8	1
5	450	443	300	8	3
6	400	453	300	8	4
7	350	443	350	8	3
8	300	453	350	8	2

Table 1.3 Failure records on solder joints under CSALTs with temperature (K) and a dichotomous variable indicating if the PCB type is “copper‐nickel‐tin (CNT)” or not.

Source: Lau et al. (1988).

Test group	Inspection time	Temperature	CNT	Number of samples	Number of failures
1	300	293	Yes	10	4
2	300	333	Yes	10	4
3	100	373	Yes	10	6
4	1300	293	No	20	10
5	800	333	No	20	3
6	200	373	No	20	4