11

V0.11P

F75367

a ground plane under the tracks if possible. Do not route D+ & D- lines next to the deflection coil of the

CRT. And also don’t route the trace across fast digital signals which can easily induce bigger error.

GND

GND

DXP

10MILS

10MILS

MINIMUM

10MILS

DXN

10MILS

Use wide tracks to minimize inductance and reduce noise pickup. 10 mil track minimum width and

spacing is recommended.

Try to minimize the number of copper/solder joints, which can cause thermocouple effects. Where

copper/solder joints are used, make sure that they are in both the D+ and D- path and at the same

temperature. Thermocouple effects should not be a major problem as 1

corresponds to about 200µV

℃

. It

means that a copper-solder thermocouple exhibits 3µV/℃, and takes about 200µV of the voltage error at

D+ & D- to cause a 1℃ measurement error. Adding a few thermocouples causes a negligible error.

Place a 0.1µF bypass capacitor close to the VCC pin. In very noisy environments, place an external

2200pF input filter capacitors across D+, D- close to the F75367.

If the distance to the remote sensor is more than 8 inches, the use of twisted pair cable is recommended.

It will work up to around 6 to 12 feet.

Because the measurement technique uses switched current sources, excessive cable and/or filter

capacitance will affect the measurement accuracy. When using long cables, the filter capacitor may be

reduced or removed. Cable resistance can also induce errors. 1 Ω series resistance introduces about

0.5

er

℃

ror.

7. Register Description

7.1.Configuration Register

 Index 01h

Bit

Name

R/W Default

Description

7-1

-

R/W

0

Reserved

0

T_START

R/W

1

Set one to enable startup of temperature monitoring operations; a zero

puts the part in standby mode.