Wavecom G900 Instrukcja Użytkownika Pobierz pdf (Strona 37)

WM2C-G900/G1800 23/09/1999

This confidential document is the property of WAVECOM and may not be copied without a written authorization

3.3.10.3. Li-ion connection example

How to choose CTN :

To have a good stability on the GPIOx voltage, (CTN + R1) must be

always bigger than 40KΩ .

How to choose R1:

R1 is choosen to have a full range of BAT-TEMP (0V to 2.5V) when

the CTN value changes from the minimum to the maximum temperature

Ex : CTN(25°C) = 47K; CTN(55°C) = 10K ; CTN(-10°C) = 300K

CTN(-10°C) x VCC = ( CTN(-10°C) + R1 ) x BAT-TEMP (full range)

R1= 47K è BAT-TEMP(-10°C) = 2.42V ;BAT-TEMP(55°C) = 0.49V

Safety

Circuitry

CTN

GND

BAT_TEMP

+VBATT

(150mΩ max)

GPIOx

Internal Battery

Resistor

1 2 ... 32 33 34 35 36 37 38 39 40 41 42 ... 50 51

Brak uwag

Wavecom G900 Instrukcja Użytkownika Strona 37