LM99EVAL National Semiconductor, LM99EVAL Datasheet - Page 14

• Manufacturer Part Number: LM99EVAL
• Description: BOARD EVALUATION LM99
• Manufacturer: National Semiconductor
• Series: PowerWise®r

Specifications of LM99EVAL

• Sensor Type: Temperature
• Sensing Range: 0°C ~ 125°C
• Interface: SMBus (2-Wire/I²C)
• Sensitivity: ±1°C
• Voltage - Supply: 3 V ~ 3.6 V
• Embedded: No
• Utilized Ic / Part: LM99
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant

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1.0 Functional Description
1.12 FAULT QUEUE
In order to suppress erroneous ALERT or T_CRIT triggering
the LM99 incorporates a Fault Queue. The Fault Queue acts
to insure a remote temperature measurement is genuinely
beyond a HIGH, LOW or T_CRIT setpoint by not triggering
until three consecutive out of limit measurements have been
made, see Figure 10. The fault queue defaults off upon
power-on and may be activated by setting bit D0 in the
Configuration register (09h) to “1”.
2.0 LM99 Registers
2.1 COMMAND REGISTER
Selects which registers will be read from or written to. Data for this register should be transmitted during the Command Byte of
the SMBus write communication.
P0-P7: Command Select
Read Address
<
P7:P0
Command Select Address
00h
01h
02h
03h
04h
05h
06h
07h
08h
NA
>
hex
Write Address
<
P7:P0
0Ch
0Dh
09h
0Ah
0Bh
0Eh
0Fh
NA
NA
NA
>
FIGURE 10. Fault Queue Temperature Response Diagram
hex
P7
P6
<
D7:D0
(Continued)
Power On Default State
0000 0000
0000 0000
0000 0000
0000 0000
0000 1000
0100 0110
0000 0000
0100 0110
0000 0000
P5
>
Command Select
binary
P4
14
P3
conv./sec)
<
decimal
1.13 ONE-SHOT REGISTER
The One-Shot register is used to initiate a single conversion
and comparison cycle when the device is in standby mode,
after which the device returns to standby. This is not a data
register and it is the write operation that causes the one-shot
conversion. The data written to this address is irrelevant and
is not stored. A zero will always be read from this register.
D7:D0
8 (16
70
70
0
0
0
0
0
0
P2
>
20053830
One Shot Writing to this register will
Register
RHSHB
RLSHB
Name
RTHB
P1
LHS
LLS
CR
SR
LT
C
P0
Local Temperature
Remote Temperature High Byte
Status Register
Configuration
Conversion Rate
Local HIGH Setpoint
Local LOW Setpoint
Remote HIGH Setpoint High
Byte
Remote LOW Setpoint High
Byte
initiate a one shot conversion
Register Function