TMP05 Analog Devices, TMP05 Datasheet - Page 15

• Manufacturer Part Number: TMP05
• Description: 0.5C Accurate PWM Temperature Sensor in 5-Lead SC-70
• Manufacturer: Analog Devices

The temperature equation for the high state conversion rate is
Table 9. Conversion Times Using Equation 3
Temperature (°C)
–40
–30
–20
–10
0
10
20
25
30
40
50
60
70
80
90
100
110
120
130
140
150
Daisy-Chain Mode
Setting the FUNC pin to a high state allows multiple TMP05/
TMP06s to be connected together and, therefore, allows one
input line of the microcontroller to be the sole receiver of all
temperature measurements. In this mode, the CONV/IN pin
operates as the input of the daisy chain, and conversions take
place at the nominal conversion rate of T
at 25°C.
Therefore, the temperature equation for the daisy-chain mode
of operation is
Temperature (°C) = 421 − (93.875 × (T
Temperature (°C) = 421 − (751 × (T
16.3
16.7
17
17.4
17.8
18.3
18.7
19
19.2
19.7
20.2
20.8
21.4
22
22.7
23.4
24.1
25
25.8
26.7
27.7
T
L
(ms)
H
H
/T
High Cycle Time (ms)
96.2
96.6
97.03
97.42
97.84
98.27
98.73
98.96
99.21
99.71
100.24
100.8
101.4
102.02
102.69
103.4
104.15
104.95
105.81
106.73
107.71
/T
H
L
/T
))
L
= 40 ms/ 76 ms
L
))
(3)
(4)
Rev. 0 | Page 15 of 28
A second microcontroller line is needed to generate the conver-
sion start pulse on the CONV/IN pin. The pulse width of the
start pulse should be less than 25 µs. The start pulse on the
CONV/IN pin lets the first TMP05/TMP06 part know that it
should start a conversion and output its own temperature now.
Once the part has output its own temperature, it then outputs a
start pulse for the next part on the daisy-chain link. The pulse
width of the start pulse from each TMP05/TMP06 part is
typically 17 µs.
Figure 26 shows the start pulse on the CONV/IN pin of the first
device on the daisy chain and Figure 27 shows the PWM output
by this first part.
MICRO
T
Figure 26. Start Pulse at CONV/IN Pin of First TMP05/TMP06 Device
OUT
0
IN
T
#1 TEMP MEASUREMENT
0
Figure 27. Daisy-Chain Temperature Measurement
CONV/IN
and Start Pulse Output from First TMP05/TMP06
TMP05/
TMP06
#1
OUT
Figure 25. Daisy-Chain Structure
MUST GO HIGH ONLY
AFTER START PULSE HAS
BEEN OUTPUT BY LAST
TMP05/TMP06 ON DAISY CHAIN.
CONV/IN
TMP05/
START
PULSE
TMP06
<25µs
on Daisy Chain
#2
TIME
OUT
TIME
CONVERSION
STARTS ON
THIS EDGE
PULSE
START
17µs
CONV/IN
TMP05/
TMP06
#3
OUT
TMP05/TMP06
CONV/IN
TMP05/
TMP06
#N
OUT