SA56004X Datasheet, PDF (33/36 Pages) NXP Semiconductors – 1 Degrees Celcious accurate, SMBus-compatible, 8-pin, remote/local digital temperature sensor with over temperature alarms

NXP Semiconductors
SA56004X
Digital temperature sensor with overtemperature alarms
2. Route the D+ and D− lines parallel and close together with ground guards enclosing
them (see Figure 25).
3. Leakage currents due to printed-circuit board contamination must be considered.
Error can be introduced by these leakage currents.
4. Use wide traces to reduce inductance and noise pick-up. Narrow traces more readily
pick up noise. The minimum width of 10 mil and space of 10 mil are recommended.
5. Place a bypass capacitor of 10 nF close to the V_DD pin and an input filter capacitor of
2200 pF close to the D+ and D− pins.
6. A shielded twisted pair is recommended if remote sensor is located several feet away
from the temperature sensor. Under this circumstance, connect the shield of the cable
at the device side to the SA56004X GND pin and leave the shield at the remote end
unconnected to avoid ground loop currents. Also notice that the series resistance of
the cable may introduce measurement error; 1 Ω can introduce about 0.5 °C.
GND
D+
D−
GND
Fig 25. D+ and D− trace layout
002aad227
16. Abbreviations
Table 22. Abbreviations
Acronym
Description
A/D
Analog-to-Digital
ARA
Alert Response Address
ASIC
Application Specific Integrated Circuit
CRT
Cathode Ray Tube
ESD
ElectroStatic Discharge
HBM
Human Body Model
HVAC
Heating, Ventilating and Air Conditioning
I²C-bus
Inter-Integrated Circuit bus
LSB
Least Significant Bit
MM
Machine Model
MSB
Most Significant Bit
OTP
One-Time Programmable
POR
Power-On Reset
PTAT
Proportional To Absolute Temperature
SMBus
System Management Bus
UVL
Under Voltage Lockout
SA56004X_5
Product data sheet
Rev. 05 — 22 May 2008
© NXP B.V. 2008. All rights reserved.
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