Analog Devices EVAL-AD2428WD1BZ Manual page 39

LEDs
2
The A B Interrupt LED is driven by the AD2428 transceiver. The LED is turned on when the IRQ/IO0 pin drives
it high. Refer to the AD2420(W)/6(W)/7(W)/8(W)/9(W) Technical Reference for further information about using
interrupts.
ADAU1452 Status ( LED2 )
The ADAU1452 Status LED is lit when the ADAU1452 SigmaDSP has been successfully programmed.
USBi ( LED3 )
The USBi LED is lit when there is an active SigmaStudio session connected to the AD2428 transceiver.
Reset ( LED4 )
When ON (red), it indicates that the board is in reset. A master reset is asserted by pressing SW1 , which activates
the LED. For more information, see Reset Pushbutton ( SW1 ).
LTC4040 Charge ( LED5 )
The LTC4040 Charge LED is lit during a battery charging cycle. CHRG is pulled low until the charge current
drops below C/8, at which point the CHRG pin becomes high impedance.
LTC4040 Fault ( LED6 )
The LTC4040 Fault LED indicates charge cycle fault conditions during a battery charging cycle. A temperature fault
or a bad-battery fault causes this pin to be pulled low. If no fault conditions exist, the FAULT pin remains high
impedance.
LTC4040 PFO ( LED7 )
The LTC4040 PFO LED is pulled to ground by an internal N-channel MOSFET when the PFI input is below the
falling threshold of the power-fail comparator. Once the PFI input rises above the rising threshold, this pin becomes
high impedance.
LTC4040 Reset ( LED8 )
The LTC4040 Reset LED is pulled to ground by an internal N-channel MOSFET whenever the RSTFB pin falls
below 0.74V. Once the RSTFB pin voltage recovers, the pin becomes high impedance after a 232ms delay.
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EVAL-AD2428WD1BZ A B Evaluation Board Manual