LM99-1EVAL/NOPB National Semiconductor, LM99-1EVAL/NOPB Datasheet
LM99-1EVAL/NOPB
Specifications of LM99-1EVAL/NOPB
Related parts for LM99-1EVAL/NOPB
LM99-1EVAL/NOPB Summary of contents
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... Contact hardware.monitor @ nsc.com for the latest details. The LM99 and LM99-1 have the same functions but different SMBus slave addresses. This allows for one of each the same bus at the same time. Activation of the ALERT output occurs when any tempera- ...
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... DC Voltage from 3 3 with a 0.1 µF capacitor in parallel with 100 pF to ground. The 100 pF capacitor should be placed as close as Positive Supply Voltage Input possible to the power supply pin. A bulk capacitance of approximately 10 µF needs the vicinity of the LM99 Diode Anode. Connected to the collector and base of Diode Current Source the remote discrete diode-connected transistor ...
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Typical Application 3 20053803 www.national.com ...
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... DD ± Operating Ratings ± (Notes Operating Temperature Range Electrical Characteristics Temperature Range 10 mA LM99 −65˚C to Supply Voltage Range (V +150˚C = +3.0 Vdc to +3.6 Vdc. Boldface limits apply for +25˚C, unless otherwise noted. Conditions T = +25˚C to +125˚C, (Note +30˚C to +50˚C and T ...
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... T A ing characteristics of the LM99 fully meet or exceed the published specifications of the SMBus version 2.0. The following pa- rameters are the timing relationships between SMBCLK and SMBData signals related to the LM99. They adhere to but are not necessarily the SMBus bus specifications. Symbol ...
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... I Parasitic components and or ESD protection circuitry are shown in the figure below for the LM99’s pins. The nominal breakdown voltage 6.5 V. Care should be taken not to forward bias the parasitic diode, D1, present on pins: D+, D−. Doing so by more than 50 mV may corrupt a temperature measurement. ...
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... ALERT mask bit in the Configuration register must be cleared to trigger an ALERT in all modes. 1.2.1 ALERT Output as a Temperature Comparator When the LM99 is implemented in a system in which it is not serviced by an interrupt routine, the ALERT output could be used as a temperature comparator. Under this method of use, once the condition that triggered the ALERT to go low is no longer present, the ALERT is de-asserted (Figure 3) ...
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... Under this method of operation, during a read of the STATUS REGISTER the LM99 will set the ALERT mask bit (D7 of the Configuration register) if any bit in the STATUS REGISTER is set, with the exception of Busy (D7) and OPEN (D2) ...
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... SMBCLK line is an input and the SMBData line is bi- directional. The LM99 never drives the SMBCLK line and it does not support clock stretching. According to SMBus specifications, the LM99 has a 7-bit slave address. All bits A6 through A0 are internally programmed and can not be changed by software or hardware. The LM99 and LM99-1 ...
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... Remote Temperature High Byte (RTHB) register is loaded with −128˚C (1000 0000) and the OPEN bit (D2) in the status register will not be set. Since operating the LM99 at −128˚C is beyond it’s operational limits, this temperature reading represents this shorted fault condition. If the value in the Remote Low Setpoint High Byte Register (RLSHB) is more than − ...
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... Register. At power-up the Command Register is set to “00”, the location for the Read Local Temperature Register. The Command Register latches the last location it was set to. Each data register in the LM99 falls into one of four types of user accessibility: 1. Read only 2. Write only 3 ...
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... Serial Bus Read from a Register with the Internal Command Register preset to desired value. 1.10 SERIAL INTERFACE RESET In the event that the SMBus Master is RESET while the LM99 is transmitting on the SMBData line, the LM99 must be returned to a known state in the communication protocol. This may be done in one of two ways: 1 ...
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... In order to suppress erroneous remote temperature readings due to noise, the LM99 incorporates a user-configured digital a) Step Response FIGURE 8. Filter Output Response to a Step Input FIGURE 9. Digital Filter Response in a Pentium 4 processor System. The filter on and off curves were purposely filter. The filter is accessed in the FILTER and ALERT CON- (Continued) FIGURE REGISTER at BFh ...
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... 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 ...
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... D7:D0 binary D7:D0 decimal 0000 0000 0 0000 0000 0 0000 0000 0 0000 0000 0 0000 0000 0 0110 1110 110 0101 0101 85 0000 1010 10 0000 0000 0 0000 0001 1 LM99 0011 0001 49 LM99-1 0011 0100 0.5 0.25 0.125 LLOW RHIGH RLOW 15 Register Register Function ...
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... LM99 Registers (Continued) 2.4 CONFIGURATION REGISTER (Read Address 03h / Write Address 09h ALERT mask RUN/STOP Power up default is with all bits “0” (zero) D7: ALERT mask: When set to “1” ALERT interrupts are masked. D6: RUN/STOP: When set to “1” SHUTDOWN is enabled. ...
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... Address FEh) Default value 01h. 2.13 DIE REVISION CODE REGISTER (Read Address FFh) The LM99 version has a default value 31h or 49 decimal. The LM99-1 version has a default value of 34h or 52 decimal. This register will increment by 1 every time there is a revision to the die by National Semiconductor. ...
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... Application Hints The LM99 can be applied easily in the same way as other integrated-circuit temperature sensors, and its remote diode sensing capability allows used in new ways as well. It can be soldered to a printed circuit board, and because the path of best thermal conductivity is between the die and the pins, its temperature will effectively be that of the printed circuit board lands and traces soldered to the LM99’ ...
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... necessary to cross high speed digital traces, the diode traces and the high speed digital traces should cross degree angle. 7. The ideal place to connect the LM99’s GND pin is as 20053817 close as possible to the Processors GND associated with the sense diode. ...
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... National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. inches (millimeters) unless otherwise noted JEDEC Registration Number MO-187 Order Number LM99CIMM or LM99CIMMX NS Package Number MUA08A 2. A critical component is any component of a life ...