SNAS668E August 2015 – September 2024 LMK03328
PRODUCTION DATA
Figure 8-1 shows the relationships between device states, the configuration pins, device initialization and configuration, and device operational modes.
In hard pin configuration mode, the state of the configuration pins determines the configuration of the device as selected from all device states programmed in the on-chip EEPROM. In soft pin configuration mode, the state of the configuration pins determines the initialized state of the device as programmed in the on-chip EEPROM.
In either mode, the host can update any device configuration after the device enables the host interface to write a sequence that updates the device registers. When the device configuration is set, the host can also write to the on-chip EEPROM for a new set of power-up defaults based on the configuration pin settings in the soft pin configuration mode. The engineer can change the state of the HW_SW_CTRL pin and trigger a device power cycle through the PDN pin to transition the device from hard pin mode to soft pin mode. In reset mode, the device disables the outputs so that unwanted sporadic activity associated with device initialization does not appear on the device outputs. Table 8-1 lists the functionality of the GPIO[5:0] pins during hard pin and soft pin modes.
PIN NAME | HARD PIN MODE | SOFT PIN MODE | ||
---|---|---|---|---|
FUNCTION | STATE | FUNCTION | STATE | |
GPIO0 | ROM page select for hard pin mode | 2 | Output synchronization (active low) | 2 |
GPIO1 | 2 | I2C target address LSB select | 3 | |
GPIO2 | 2 | EEPROM page select for soft pin mode or register default mode | 3 | |
GPIO3 | 2 | 3 | ||
GPIO4 | 2 | Frequency margining enable | 2 | |
GPIO5 | 2 | Frequency margining offset select | 8 |