The motivation for this question comes from the fact that some time ago I created a simple proof of concept (PoC) IoT edge device using a microcontroller and a CC3100 Wifi network processor. One of the problems with this prototype was that the configuration required a considerable amount power. Thus, it could not overcome the benefits of the existing lower power device which could last for over 2 to 10 years depending on choice of battery and usage frequency.
Depending on the application, the current product uses a 6V DC battery with a capacity between 1400 mAh and 2400 mAh. The device has a low power sensing element and an actuating mechanism. The payload most likely will be around 100 bytes. The frequency of communication will be about every two minutes during peak activity. With the advances in the IoT and market demands, this PoC has gained some attention.
Per the suggestion of few IOT platform providers I am looking at CC3200 wireless MCU from Texas Instrument primarily because it is the successor to the CC3100. At a system level when not in use the CC3100 power can be completely switched off. This is a significant advantage for low power at a systems level. When activity is detected the sensing element wakes up the microcontroller via an interrupt. There are other integrated wifi MCU’s such as ESP8266, BCM43362, ATWINC1500B, 88MC200 and many more. I use ULPBench Scores to do a first order analysis of low power microcontrollers followed by analysis such as described in How to select a micro controller for a low power application? to help select a low power microcontroller. I have used parameters such as active mode current draw per frequency, and current draw a different low power modes to make an informed selection. So in order to maintain the low power option and to add IoT capability, what are critical parameters (may related to wireless communication) that I should I pay close attention to when selecting an integrated wifi MCU?