Datasheet

MCP9600
DS20005426C-page 22  2015-2017 Microchip Technology Inc.
The MCP9600 device has several registers that are
user-accessible. These registers include the Thermo-
couple Temperature (cold-junction compensated),
Hot-Junction Temperature, Cold-Junction Temperature,
Raw ADC Data, user-programmable Alert Limit
registers, and STATUS and Configuration registers.
The Temperature and the Raw ADC Data registers are
read-only registers, used to access the thermocouple
and the ambient temperature data. In addition, the four
Alert Temperature registers are individually controlled,
and can be used to detect a rising and/or a falling
temperature change. If the ambient temperature drifts
beyond the user-specified limits, the MCP9600 device
outputs an alert flag at the corresponding pin (refer to
Section 5.3.3 “Alert Configuration Registers”). The
alert limits can also be used to detect critical
temperature events.
The MCP9600 also provides STATUS and Configura-
tion registers, which allow users to detect device sta-
tuses. The Configuration registers provide various
features, such as adjustable temperature measure-
ment resolution and Shutdown modes. The thermocou-
ple types can also be selected using the Configuration
registers.
The registers are accessed by sending a Register
Pointer to the MCP9600 using the serial interface. This
is an 8-bit write-only pointer. Register 5-1 describes the
pointer definitions.
REGISTER 5-1: REGISTER POINTER
U-0 U-0 U-0 U-0 W-0 W-0 W-0 W-0
— — — —P<3:0>
bit 7 bit 0
Legend:
R = Readable bit W = Writable bit U = Unimplemented bit, read as ‘0’
-n = Value at POR ‘1’ = Bit is set ‘0’ = Bit is cleared x = Bit is unknown
bit 7-4 Unimplemented: Read as ‘0’
bit 3-0 P<3:0>: Pointer bits
0000 0000 = Thermocouple Hot-Junction register, T
H
0000 0001 = Junctions Temperature Delta register, T
∆
0000 0010 = Cold-Junction Temperature register, T
C
0000 0011 = Raw ADC Data register
0000 0100 = STATUS register
0000 0101 = Thermocouple Sensor Configuration register
0000 0110 = Device Configuration register
0000 1000 = Alert 1 Configuration register
0000 1001 = Alert 2 Configuration register
0000 1010 = Alert 3 Configuration register
0000 1011 = Alert 4 Configuration register
0000 1100 = Alert 1 Hysteresis register, T
HYST1
0000 1101 = Alert 2 Hysteresis register, T
HYST2
0000 1110 = Alert 3 Hysteresis register, T
HYST3
0000 1111 = Alert 4 Hysteresis register, T
HYST4
0001 0000 = Temperature Alert 1 Limit register, T
ALERT1
0001 0001 = Temperature Alert 2 Limit register, T
ALERT2
0001 0010 = Temperature Alert 3 Limit register, T
ALERT3
0001 0011 = Temperature Alert 4 Limit register, T
ALERT4
0010 0000 = Device ID/Revision register