Folks,
Let's see how Monica and Guy are doing in solving the too-high temperature reflow concern.....
Patty was sitting in her office, and, typical to her dynamic personality, was excited and annoyed at the same time. The excitement was because Monica Reese and Guy D’Argent were stopping by her office to discuss how they were doing in solving Monica’s low temperature soldering challenge.
She was annoyed, however, because of a mistake that a supposedly-prestigious guest professor made in a lecture she attended. He was discussing the growth rate of sales of an electronic device. The sales had doubled in 8 years, so he said, ”Since the sales doubled in 8 years, that is a 100% growth, so 100%/8 = 12.5%. So the growth rate was 12.5% per year.”
The lecturer treated the data as linear, when it was not. If he used “The Rule of 72,” he would have seen that the growth rate was 72/8 = 9%, not 12.5%. Patty worried a bit that she was becoming cranky, getting annoyed at things like this. But, she reasoned with herself, a professor should know these things.
She focued on her excitement at meeting with Guy and Monica. Just as she had this thought, they showed up at her door. As they walked in Patty said, “Bonjour, ca va tres bien?” (Hello, things are good?)
Monica and Guy were, once again, taken aback, as they had forgotten Patty’s French was so good. After exchanging pleasantries in French, they reverted to English.
“So, how did you make out with the low temperature assembly challenge?” Patty asked.
“It worked out really well!” Monica shared excitedly. “Guy recommended a reflow profile using Durafuse®LT solder paste that worked perfectly for my application. The profile has a peak temperature of 210°C, so the components that can only be exposed to 220°C or less are fine.”
Figure 1. Monica and Guy settled on the light green profile shown in this image, as it peaked below the 220°C concern at 210°C.
"We performed a few quick drop shock tests and there were no fails,” Guy added.
“My bosses are ecstatic, as am I,” Monica shared.
They continued to chat about this success. Patty noticed that Monica and Guy were holding hands.
The meeting was wrapped up a few minutes later. As Patty watched the young couple leaving her office, she was in a wistful mood. Could it be that she was now middle age? She was always the young superstar. She hoped she was still a superstar, but she no longer felt young knowing her twin boys were freshmen in college. A slight tear welled up in her eye. Despite its appearance, it was a tear of gratefulness, as life has worked out quite well so far for Professor Patty Coleman, PhD. PE.
Cheers,
Dr. Ron