example when the supply voltage to the module experiences a Brown- Out (momentary dip in the supply voltage level), or a rapid power cycle i.e. the power is switched off and then on within 1second, there is a possibility that the module can enter an unknown state of operation.

It is strongly recommended that the application hardware onto which the module is mounted provides a Power-On-Reset circuit with a Brown-Out detection capability. This will guarantee that under all circumstances the module will operate in a known state.

A device such as the Maxim MAX6382XR26D3-T would be a suitable part to perform the reset – it has an active high push-pull output, a 2.63V detection threshold, and an active reset period of 140ms. This inexpensive device is available in a SC70-3 package (2.2mm x 2.4mm) and requires no additional components to operate. The device is used to monitor the output of the voltage regulator on the module (through pin 27), and drives the Reset line (pin13) high when the supply voltage falls out of tolerance. The schematic below illustrates its use.

Please note that this 3V3 is the output of the 3V3 regulator on the blu2i Module and should not be connected to any other supplies on the application hardware.

blu2i Module

BC02 3V3 Pin27

 

 

 

 

 

 

 

 

 

 

 

 

3

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Vcc

 

 

 

MAX6382

 

Gnd

 

 

 

Reset

 

 

 

 

 

 

 

 

 

 

 

1

 

 

2

 

 

 

 

 

 

 

 

 

 

 

BC02 MRESET Pin13

10K

GND

GND

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