Q2406B

Manufacturer Part NumberQ2406B
ManufacturerWAVECOM
Q2406B datasheet
 


Specifications of Q2406B

Date_code06+  
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
Page 31
32
Page 32
33
Page 33
34
Page 34
35
Page 35
36
Page 36
37
Page 37
38
Page 38
39
Page 39
40
Page 40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
Page 38/81

Download datasheet (903Kb)Embed
PrevNext
2.13.1 Li-ion charging procedure
A constant current source has to be provided through CHG_IN input in order to
charge the Li-ion battery, and BAT_TEMP input has to be connected to a
battery temperature sensor. During this procedure the voltage of the battery is
accurately monitored.
The Li-ion charging involves two phases. During the first phase, the battery is
charged with a constant current until its voltage reaches 4.1V*. During the
second phase the constant current is pulsed by the module. The width and the
frequency of the pulse change during this phase in order to ensure a safety
charge. The battery is considered as fully charged when, after a pulse, the
voltage remains at a 4.1V* during more than 10s.
The Li-ion battery must have an included safety circuit to avoid any discharge
or overcharge. This circuit is delivered by the manufacturer inside the battery
pack. The impedance of this safety circuit has to be the lowest possible in
order to reduce the drop-out of the voltage. This drop-out is due to the RF
Power Amplifier current (up to 2.0A). A maximum of 150mΩ is required.
(*) : To be parametrized as per battery manufacturer
2.13.2 How to define R1 and C1
How to choose R1
R1 has to be chosen to have a full range of BAT-TEMP (from 0V to 2.8V) when
the CTN value changes from the minimum to the maximum temperature
How to choose C1
C1 has to be chosen to have a RC filter with a time constant lower than 2ms.
Calculation examples
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 " BAT-TEMP(-20°C) = 2.42V
BAT-TEMP(55°C) = 0.49V
R(-20°C) = R1//CTN(-10°C) = 40K
R(+55°C) = 8K
With C= 10nF ::
RC(-20°C) = 400µs
RC(+55°C) = 80µs
confidential ©
This document is the sole and exclusive property of WAVECOM. Not to be distributed or divulged
without prior written agreement.
Ce document est la propriété exclusive de WAVECOM. Il ne peut être communiqué ou divulgué à
des tiers sans son autorisation préalable.
WM_PRJ_Q2400_PTS_002 - 002
24th January 2003
Page : 38 / 81