Pre-requisites

Powering up the FlexCase E/G and S models.

Intro

When the FlexCase is not in use, it enters a sleep mode to reduce power consumption. During this time, most of the FlexCase’s functions are turned off, but a minimal circuit remains active to monitor the CAN / LIN bus.

In general, there are four methods that can be used to control power on the FlexCase. Ignition pin, Keep alive from MCU, wake signal from CAN, and wake signal from LIN are the four methods. These methods are connected with an “OR” logic. It means that a high logic on any of these four signals can turn/keep the FlexCase ON. Also, in order to turn OFF the FlexCase, you need to have low logic on all of the mentioned signals.

The following table gives a brief on the available power up features available in the various FlexCase units.

All the FlexCases can be powered up through the Ignition switch. Wake on CAN and LIN are available only on specific models as listed above.

Powering up the unit:

• Ignition Pin: The active HIGH power-up feature is typically accessible via an external switch included in all prototyping FlexCase kits. This switch serves as the primary wake signal for the MCU. When the switch is pressed and held, VBATT connects to the IGNITION input pin, delivering the wake signal to the FlexCase.
• Wake on CAN: When a CAN message comes in, the unit wakes from sleep mode and processes the CAN message. This wake signal will also be enabled when power is initially applied.
• Wake on LIN: When a LIN message comes in, the unit wakes from sleep mode and processes the LIN message. This wake signal will also be enabled when power is initially applied.

Powering down the unit:

• Ignition Switch: The ignition pin can be released removed (Switch released), to power down the unit.
• To Disable Wake on CAN Signal:
  • Set “MCU CAN Enable” HIGH
  • Toggle “nSTB” to HIGH
  • Toggle “nSTB” to LOW
  • Note 1: Give every step at least 100ms.
  • Note 2: Every time that VBATT and GND connect to FlexCase, wake on CAN signal will be set high automatically.
• To Disable Wake on LIN Signal:
  • Toggle “LIN Enable” HIGH
  • Toggle “LIN Enable” LOW
  • Note 1: Give every step at least 100ms.
  • Note 2: Every time that VBATT and GND connect to FlexCase, wake on LIN signal will be set high automatically.
• Keep Alive: When the FlexCase is ON, MCU can keep the FlexCase ON by controlling the Keep On GPIO pin. Driving this GPIO high from the MCU, will provide the high logic wake signal. A low logic on the GPIO will remove the Keep Alive wake signal. This feature can be used for soft shutdown process.