tc72-5.0mmf Microchip Technology Inc., tc72-5.0mmf Datasheet - Page 12

• Manufacturer Part Number: tc72-5.0mmf
• Description: Digital Temperature Sensor With Spi? Interface
• Manufacturer: Microchip Technology Inc.

TC72
4.0
The TC72 registers are listed below.
TABLE 4-1:
4.1
The Control register is both a read and a write register
that is used to select either the Shutdown, Continuous
or One-Shot Conversion operating mode. The Temper-
ature Conversion mode selection logic is shown in
Table 4-2. The Shutdown (SHDN) bit is stored in bit 0
of the Control register. If SHDN is equal to ‘1’, the TC72
will go into the power-saving shutdown mode. If SHDN
is equal to ‘0’, the TC72 will perform a temperature
conversion approximately every 150 ms.
At power-up, the SHDN bit is set to ‘1’. Thus, the TC72
is in the shutdown operating mode at startup. The Con-
tinuous Temperature Conversion mode is selected by
writing a ‘0’ to the SHDN bit of the Control register.
The Shutdown mode can be used to minimize the
power consumption of the TC72 when active tempera-
ture monitoring is not required. The shutdown mode
disables the temperature conversion circuitry; how-
ever, the serial I/O communication port remains active.
A temperature conversion will be initialized by a Write
operation to the Control register to select either the
Continuous Temperature Conversion or the One-Shot
operating mode. The temperature data will be available
in the MSB and LSB Temperature registers approxi-
mately 150 ms after the Control register Write
operation.
TABLE 4-2:
DS21743A-page 12
Control
LSB Temperature
MSB Temperature
Manufacturer ID
Continuous Temperature Conversion
Shutdown
Continuous Temperature Conversion
(One-Shot Command is ignored if SHDN = ‘0’)
One-Shot
Register
INTERNAL REGISTER
STRUCTURE
Control Register
Operational Mode
REGISTERS FOR TC72
CONTROL REGISTER TEMPERATURE CONVERSION MODE SELECTION
Address
00hex
01hex
02hex
03hex
Read
Address
80hex
Write
N/A
N/A
N/A
Bit
T1
T9
0
0
7
Bit
T0
T8
6
0
1
One-Shot (OS) Bit 4
T7
Bit
0
0
5
0
The One-Shot mode is selected by writing a ‘1’ into bit
4 of the Control register. The One-Shot mode performs
a single temperature measurement and returns to the
power-saving shutdown mode. After completion of the
temperature conversion, the One-Shot bit (OS) is reset
to ‘0’ (i.e. “OFF”). The user must set the One-Shot bit
to ‘1’ to initiate another temperature conversion.
Bits 1, 3, 5, 6 and 7 of the Control register are not used
by the TC72. Bit 2 is set to a logic ‘1’. Any write opera-
tion to these bit locations will have no affect on the
operation of the TC72.
4.2
The Temperature register is a read-only register and
contains a 10-bit two’s complement representation of
the temperature measurement. Bit 0 through Bit 5 of
the LSB Temperature register are always set to a logic
‘0’.
At Power-On Reset (POR) or a Brown-Out Reset
(BOR) low voltage occurrence, the temperature regis-
ter is reset to all zeroes, which corresponds to a tem-
perature value of 0°C. A V
1.6V is considered a reset event and will reset the
Temperature register to the power-up state.
4.3
The Manufacturer Identification (ID) register is a read-
only register used to identify the temperature sensor as
a Microchip component.
One-Shot
(OS)
0
0
1
1
Bit
T6
4
0
1
Temperature Register
Manufacturer ID Register
Bit
T5 T4 T3
3
0
0
0
Bit
2
1
0
1
Bit
1
0
0
0
Shutdown (SHDN) Bit 0
2002 Microchip Technology Inc.
Shutdown
DD
(SHDN)
Bit
T2
power supply less than
0
0
0
0
1
0
1
POR/BOR
Value on
05hex
00hex
00hex
54hex