Rainbow Electronics MAX6683 - Manual (Page 6)

MAX6683
Unless the fault is removed, the ALERT output only
remains cleared until the end of the next conversion
cycle where it is again asserted. The ALERT output can
also be masked by writing to the appropriate bits in the
Interrupt Mask Register (Table 6) or by setting bit 1 of
the Configuration Register (Table 4) to zero.
The 2-wire serial interface accepts both I 2 C and stan-
dard SMBus Write Byte, Read Byte, Read Word, Send
Byte, and Receive Byte commands to program the
alarm thresholds and to read voltage and temperature
data. Voltage data is scaled so that when the nominal
voltage is present at an input (e.g., 1.8V for the 1.8V
IN
input), the conversion result is equal to 3/4 of the ADC
full-scale range or a decimal count of 192 (Table 1).
When using the Read Byte command, the temperature
data format is 7 bits plus sign with the LSB equal to
1°C, in two's complement format. When using the Read
Word command, the temperature data format is 10 bits
plus sign, with the LSB equal to 0.125°C, in two’s com-
plement format. See Table 2 for the temperature data
format.
The MAX6683 has only one address input, ADD.
Connect ADD to GND, V
CC , SDA, or SCL to select one
of four different address codes. Whenever an
SMBus/I
2 C transaction is initiated, the 2LSBs of the
Slave Address Register are determined by connection,
setting the chip address to one of four possible values.
In addition, an address code can also be directly writ-
Temperature Sensor and System Monitor
in a 10-Pin µMAX
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Table 1. Register Map
ADDRESS READ/WRITE POWER-ON DEFAULT DESCRIPTION
20h R — Data register for 2.5 V IN measurement
21h R — Data register for 1.8V IN measurement
22h R — Data register for 5V IN measurement
23h R — Data register for V CC measurement
27h R — Data register for temperature measurement
2Bh R/W 1101 0011 (1.1 × 2.5V) High limit for 2.5V IN
2Ch R/W 1010 1101 (0.9 × 2.5V) Low limit for 2.5V IN
2Dh R/W 1101 0011 (1.1 × 1.8V) High limit for 1.8V IN
2Eh R/W 1010 1101 (0.9 × 1.8V) Low limit for 1.8V IN
2Fh R/W 1101 0011 (1.1 × 5V) High limit for 5V IN
30h R/W 1010 1101 (0.9 × 5V) Low limit for 5V IN
31h R/W 1101 0011 (1.1 × 3.3V) High limit for V CC
32h R/W 1010 1101 (0.9 × 3.3V) Low limit for V CC
39h R/W 0101 0000 (+80°C) Hot temperature limit
3Ah R/W 0100 0001 (+65°C) Hot temperature hysteresis
40h R/W 0000 1000 Configuration Register
41h R 0000 0000 Interrupt Status Register
43h R/W 0000 0000 Interrupt Mask Register
48h R/W 0010 1XXY
Device Address Register. The values of XX are
dependent on the status of the ADD pin.
Power-On Default ADD Connection
0010 100Y To GND
0010 101Y To V
CC
0010 110Y To SDA
0010 111Y To SCL
Y (bit 0) is the SMBus read/write bit. When the 7-bit chip
address is read back from the Serial Address Register,
an 8-bit word is presented with a zero in bit 0 (Y).
4Bh R/W 0000 0000 Temperature Configuration Register