Rainbow Electronics MAX6683 - Manual (Page 8)

MAX6683
The POR state of the T HOT register is 0101 0000 or
+80°C. The POR state of the T
HYST
register is 0100
0001 or +65°C.
High and low limits for the voltage inputs are stored in
registers 2Bh through 32h. If a measured voltage is less
than V
LOW or greater than V HIGH , an ALERT is asserted.
The POR states of the high and low voltage limits are
1.1 and 0.9 times the nominal voltage for each input.
Interrupt Status Byte Functions
The Interrupt Status Register records temperature or
voltage fault conditions whenever a limit is exceeded
(Table 5). Bits 0 through 3 correspond to the 2.5V, 1.8V,
5V, and V
CC voltage inputs and bit 4 corresponds to
the temperature. If a threshold has been crossed, the
appropriate bit contains a 1. In the default and one-time
interrupt modes, reading the status register clears the
register until a new out-of-range condition is detected.
Temperature Sensor and System Monitor
in a 10-Pin µMAX
8 _______________________________________________________________________________________
Table 4. Configuration Register (Address 40h, Power-On Default = 08h)
BIT NAME READ/WRITE DESCRIPTION
0 Start/Stop R/W
This bit controls the monitoring loop. Setting the bit to zero stops the
monitoring loop and puts the device into shutdown mode. The I
2 C/SMBus
interface is still active during the shutdown mode. Setting the bit to 1 starts the
monitoring cycle. All high/low limits should be set before setting this bit to 1.
1 ALERT Enable R/W
This bit is used to enable or disable the ALERT output. Setting the bit to 1
enables the ALERT output; setting the bit to 0 disables the ALERT output.
2 Reserved — —
3 ALERT Clear R/W
This bit is used to clear the ALERT output when it is set to high. It does not
affect the Interrupt Status Register. The monitoring loop does not start until the
bit is set to zero.
4
Line Frequency
Select
R/W
This bit controls the internal clock frequency. Setting the bit to 1 changes the
clock frequency to 51.2kHz from 61.4kHz. This can improve the measurement
accuracy when the power-line frequency is at 50Hz.
5 Short Cycle R/W This bit reduces the conversion time by a factor of 4 when it is set to 1.
6 Reserved — —
7 Reset R/W
This bit is used as a reset signal for the register initialization. The 1 of this bit
resets all the register values into the power-up default mode, including bit 7
itself.
Table 5. Interrupt Status Register (Address 41h, Power-Up Default = 00h)
BIT NAME READ/WRITE DESCRIPTION
0 2.5V IN -Error R A 1 i nd i cates ei ther a hi g h or l ow l i m i t has b een exceed ed at the 2.5V IN i np ut.
1 1.8V IN -Error R A 1 i nd i cates ei ther a hi g h or l ow l i m i t has b een exceed ed at the 1.8V IN i np ut.
2 5V IN -Error R A 1 i nd i cates ei ther a hi g h or l ow l i m i t has b een exceed ed at the 5V I N i np ut.
3 V CC -Error R A 1 i nd i cates ei ther a hi g h or l ow l i m i t has b een exceed ed at the V C C i np ut.
4 Temp-Error R
A 1 indicates either a high or low limit has been exceeded at the internal
temperature sensor. The conditions that generate and clear this bit depend
on the temperature interrupt mode selected by bits 0 and 1 in the
Temperature Configuration Register.
5, 6, 7 Reserved — —