Datasheet
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SBOS231G − JANUARY 2002 − REVISED NOVEMBER 2007
www.ti.com
6
equal to zero. Data format for temperature is summarized
in Table 5. Following power-up or reset, the Temperature
Register will read 0°C until the first conversion is complete.
Table 3. Byte 1 of Temperature Register
D7 D6 D5 D4 D3 D2 D1 D0
T11 T10 T9 T8 T7 T6 T5 T4
Table 4. Byte 2 of Temperature Register
D7 D6 D5 D4 D3 D2 D1 D0
T3 T2 T1 T0 0 0 0 0
Table 5. Temperature Data Format
TEMPERATURE
(°C)
DIGITAL OUTPUT
(BINARY)
HEX
128 0111 1111 1111 7FF
127.9375 0111 1111 1111 7FF
100 0110 0100 0000 640
80 0101 0000 0000 500
75 0100 1011 0000 4B0
50 0011 0010 0000 320
25 0001 1001 0000 190
0.25 0000 0000 0100 004
0.0 0000 0000 0000 000
−0.25 1111 1111 1100 FFC
−25 1110 0111 0000 E70
−55 1100 1001 0000 C90
−128 1000 0000 0000 800
The user can obtain 9, 10, 11, or 12 bits of resolution by
addressing the Configuration Register and setting the
resolution bits accordingly. For 9-, 10-, or 11-bit resolution,
the most significant bits in the Temperature Register are
used with the unused LSBs set to zero.
CONFIGURATION REGISTER
The Configuration Register is an 8-bit read/write register
used to store bits that control the operational modes of the
temperature sensor. Read/write operations are performed
MSB first. The format of the Configuration Register for the
TMP100 and TMP101 is shown in Table 6, followed by a
breakdown of the register bits. The power-up/reset value
of the Configuration Register is all bits equal to 0. The
OS/ALERT bit will read as 1 after power-up/reset.
Table 6. Configuration Register Format
BYTE D7 D6 D5 D4 D3 D2 D1 D0
1 OS/ALERT R1 R0 F1 F0 POL TM SD
SHUTDOWN MODE (SD)
The Shutdown Mode of the TMP100 and TMP101 allows
the user to save maximum power by shutting down all
device circuitry other than the serial interface, which
reduces current consumption to less than 1µA. For the
TMP100 and TMP101, Shutdown Mode is enabled when
the SD bit is 1. The device will shutdown once the current
conversion is completed. For SD equal to 0, the device will
maintain continuous conversion.
THERMOSTAT MODE (TM)
The Thermostat Mode bit of the TMP101 indicates to the
device whether to operate in Comparator Mode (TM = 0)
or Interrupt Mode (TM = 1). For more information on
comparator and interrupt modes, see the HIGH and LOW
Limit Registers section.
POLARITY (POL)
The Polarity Bit of the TMP101 allows the user to adjust the
polarity of the ALERT pin output. If POL = 0, the ALERT pin
will be active LOW, as shown in Figure 4. For POL = 1 the
ALERT pin will be active HIGH, and the state of the ALERT
pin is inverted.
Measured
Temperature
T
HIGH
T
LOW
TMP101 ALERT PIN
(Comparator Mode)
POL = 0
TMP101 ALERT PIN
(Interrupt Mode)
POL = 0
TMP101 ALERT PIN
(Comparator Mode)
POL = 1
TMP101 ALERT PIN
(Interrupt Mode)
POL = 1
Read Read
Time
Read
Figure 4. Output Transfer Function Diagrams
FAULT QUEUE (F1/F0)
A fault condition occurs when the measured temperature
exceeds the user-defined limits set in the T
HIGH
and T
LOW
Registers. Additionally, the number of fault conditions
required to generate an alert may be programmed using
the Fault Queue. The Fault Queue is provided to prevent
a false alert due to environmental noise. The Fault Queue
requires consecutive fault measurements in order to
trigger the alert function. If the temperature falls below
T
LOW
, prior to reaching the number of programmed
consecutive faults limit, the count is reset to 0. Table 7
defines the number of measured faults that may be
programmed to trigger an alert condition in the device.