Run; Saved; Sleep Mode; Wake-Up Sequences - Analog Devices MAX96752 User Manual

The device can enter the boot state from reset after external supplies have ramped up or the device has resumed
operation from sleep. In boot, all power switches are turned on, and all power manager sub-blocks are enabled.
When all post-switch supplies are valid, the chip enters run state. The power manager has an inrush current control
feature. In boot state, the core supply switches are turned on gradually.

RUN

The run state is the normal operating mode of the device. The device enters run when all power supplies to the chip
are valid. Once entering this state, the crystal begins to warm up, on-board calibration is initiated, and the GMSL
handshake begins the process of establishing link lock.

SAVED

Saved mode is initiated with an I
manager enters the saved state, the core saves the current device configuration and register values to retention
memory. In the saved state, all power switches are turned off and the power manager blocks are disabled. The
device enters the sleep state.

Sleep Mode

Sleep mode provides a low power state from which prior configuration information is automatically loaded upon
wakeup. This enables very fast recovery from low power sleep to full run operation by eliminating the need for the
user to reprogram configuration registers as is required after a full power cycle.
In Run mode (normal operation), writing (SLEEP=1) starts the process of saving device configuration and register
settings. The power manager shuts down all internal power supplies, the clocks are disabled, and the chip enters
the very low power consumption sleep state. V
retention memory, and it is recommended that all supplies be maintained in their nominal operating range.
All GPIO pins are Hi-Z in power-down and sleep states.

Wake-up Sequences

There are two ways to wake up from Sleep mode:
• Local Wake-Up: Local wake-up entails the local host processor initiating a dummy control channel
transaction, which briefly wakes up the device. In I2C mode, the initial temporary wake-up requires four
falling edges on SDA. Depending on the device address used, there may need to be multiple consecutive
dummy transactions issued by the host to achieve the required four SDA falling edges. The dummy
transaction(s) must immediately be followed by the host processor setting SLEEP=0 to permanently exit
Sleep mode. The device automatically returns to Sleep mode if SLEEP remains set to 1.
• Remote Wake-Up: All GMSL devices include wake-up detectors to observe GMSL link activity and briefly
turn on the device when activity is detected. The link can then lock, providing an opportunity for a remote
host to disable Sleep mode (setting SLEEP=0). The device automatically reverts to Sleep mode if SLEEP
remains set to 1.

Sleep Mode Limitations

Sleep mode should not be used in conjunction with RESET_ALL.
The GMSL2 family includes a global soft reset function called RESET_ALL. This is a self-clearing reset command that
is intended to reset all sub-systems to their default configurations. However, if a device has previously gone
through a sleep/wake cycle, issuing a
retention memory that had been stored when the most recent
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2 C/UART command (SLEEP = 1) while the device is in run. Before the power
must remain stable to provide continuous power to the data
DD18
RESET_ALL resets the device and erroneously loads the contents of the
SLEEP command was executed. As a result, the
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