DATASHEET

Copyright

2017, EM Microelectronic-Marin SA

8900-DS, Version 4.1, 30-Mar-17

11

www.emmicroelectronic.com

420005-A01, 3.0

6.3.4. TEG SELECTION EXAMPLE 1

This example assumes an industrial application operated with a TEG element attached to a hot water pipe on the hot side and

connected to a cooling element of 10 [K/W] in ambient air on the cold side.

The electronic system requires an average power of 1 mW and must operate fully autonomously. The maximum output voltage

is 4.2V.

We arrive at the following selection of parameter values:

1.

The best transformer turn ratio in this power range is 1:20

2.

The ideal TEG thermal resistivity is 10 [K/W]

3.

4.

According to the Figure 5-13, the ideal TEG electrical resistivity is about 4

Ω at 1 mW.

The following TEG by Marlow offers characteristics close these values:

Part number:

NL1023T-01AC

Thermal resistivity:

11.30 [K/W]

Electrical resistivity:

3.50 [

Ω]

Seebeck coefficient: 27 [mV/K]

6.3.5. TEG SELECTION EXAMPLE 2

This application example assumes a wearable device in contact with the skin on the hot side and TEG with a cooling element of

100 [K/W] in ambient air. The electronic system requires an average power of 20

μW and operates fully autonomously. The

maximum output voltage is 2.0V.

1.

The best turn ratio for the transformer in this power range is 1:100

2.

The ideal TEG thermal resistivity is 100 [K/W]

3.

4.

According to the Figure 5-7, the ideal TEG electrical resistivity is about 2

Ω at 20μW.

The following TEG by Marlow offers characteristics close to these values when 2 elements are electrically connected in series

and thermally connected in parallel:

Part number:

1x NL1010T-01AC

2x NL1010T-01AC

Thermal resistivity:

191.40 [K/W]

95.7 [K/W]

Electrical resistivity:

0.64 [

Ω]

1.28 [

Ω]

Seebeck coefficient: 2.665 [mV/K]

5.33 [mV/K]

6.4. CAPACITOR SELECTION

that capacitor depends on the current amplitude in the primary side of the transformer, the input voltage average and the

Input power

range

Up to 100 μW

47 μF

100

μW to 1 mW

100 μF

Above 1 mW

470 μF