Datasheet

TMP100−EP
DIGITAL TEMPERATURE SENSOR
WITH I
2
C INTERFACE
SGLS254B − JULY 2005 − REVISED OCTOBER 2013
7
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
APPLICATION INFORMATION
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.
Byte D7 D6 D5 D4 D3 D2 D1 D0
1 OS/ALERT R1 R0 F1 F0 POL TM SD
Table 6. Configuration Register Format
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 1 μA. For the
TMP100 and TMP101, shutdown mode is enabled when the SD bit is 1. The device shutdowns once the current
conversion is completed. For SD equal to 0, the device maintains 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 and SMBus alert function sections.
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 3. 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 3. Output Transfer Function Diagrams