Manual

CS5460A
DS487F5 49
allow the corresponding bit in the Status Register to activate the INT pin when the status bit becomes active.
IC
Invalid Command. Normally logic 1. Set to logic 0 when the part is given an invalid command.
Can be deactivated only by sending a port initialization sequence to the serial port (or by exe-
cuting a software/hardware reset). When writing to the Status Register, this bit is ignored.
LSD Low Supply Detect. Set when the voltage at the PFMON pin falls below the low-voltage thresh-
old (PMLO), with respect to VA- pin. For a given part, PMLO can be as low as 2.3 V. LSD bit
cannot be permanently reset until the voltage at PFMON pin rises back above the high-voltage
threshold (PMHI), which is typically 100mV above the device’s low-voltage threshold. PMHI will
never be greater than 2.7 V.
IOD Modulator oscillation detect on the current channel. Set when the modulator oscillates due to
an input above Full Scale. Note that the level at which the modulator oscillates is significantly
higher than the current channel’s Differential Input Voltage Range.
VOD Modulator oscillation detect on the voltage channel. Set when the modulator oscillates due to
an input above Full Scale. Note that the level at which the modulator oscillates is significantly
higher than the current channel’s Differential Input Voltage Range.
Note: The IOD and VOD bits may be ‘falsely’ triggered by very brief voltage spikes from the
power line. This event should not be confused with a DC overload situation at the
inputs, when the IOD and VOD bits will re-assert themselves even after being
cleared, multiple times.
WDT Watch-Dog Timer. Set when there has been no reading of the Energy Register for more than
5 seconds. (MCLK = 4.096 MHz, K = 1) To clear this bit, first read the Energy Register, then
write to the Status Register with this bit set to logic '1'. When MCLK/K is not 4.096 MHz, the
time duration is 5 * [4.096 MHz / (MCLK/K)] seconds.
ID3:0 Revision/Version Identification.
EOOR The internal EOUT
Energy Accumulation Register went out of range. Note that the EOUT En-
ergy Accumulation Register is different than the Energy Register available through the serial
port. This register cannot be read by the user. Assertion of this bit can be caused by having
an output rate that is too small for the power being measured. The problem can be corrected
by specifying a higher frequency in the Pulse-Rate Register.
EOR Energy Out of Range. Set when the Energy Register overflows, because the amount of energy
that has been accumulated during the pending computation cycle is greater than the register’s
highest allowable positive value or below the register’s lowest allowable negative value.
VROR RMS Voltage Out of Range. Set when the calibrated RMS voltage value is too large to fit in the
RMS Voltage Register.
IROR RMS Current Out of Range. Set when the calibrated RMS current value is too large to fit in the
RMS Current Register.
PWOR Power Calculation Out of Range. Set when the magnitude of the calculated power is too large
to fit in the Instantaneous Power Register.
VOR Voltage Out of Range.
IOR Current Out of Range. Set when the magnitude of the calibrated current value is too large or
too small to fit in the Instantaneous Current Register.
MATH General computation Indicates that a divide operation overflowed. This can happen normally
in the course of computation. If this bit is asserted but no other bits are asserted, then there is
no error, and this bit should be ignored.