Specifications

WM_PRJ_Q2400_PTS_002 - 002
24th January 2003
confidential ©
Page :
34 / 81
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.
Nevertheless in a 32 Ohms speaker case, you should use a cheaper and
smaller solution : R1 = 82 Ohm et C2 = 4.7µF (ceramic)
The gain of SPK outputs is internally adjusted and can be tuned using an AT
command.
Speaker gain vs Max output voltage
Receive Gain (dB) (*) Max output level
(Vrms)
AT+VGR (**)
Max.speaker load (
Ω
)
+2 1.74 0 to 15 150
0 1.38 16 to 31 50
-2 1.099 32 to 47 32
-4 0.873 48 to 63 32
-6 0.693 64 to 79 32
-8 0.551 80 to 95 32
-10 0.437 96 to 111 32
-12 0.347 112 to 127 32
-14 0.276 128 to 143 32
-16 0.219 144 to 159 32
-18 0.174 160 to 175 32
-20 0.138 176 to 191 32
-22 0.110 192 to 207 32
-24 0.087 208 to 223 32
-26 0.069 224 to 239 32
-26 0.069 240 to 255 32
(*) analog gain : might not be significant
(**) control of the receive gain by AT commands (for WISMO Quik Q24x6
Series driven by AT commands)
Recommended characteristics for the speaker:
•
Type : 10 mW, electro-magnetic
•
Impedance : 32 to 150
Ω
•
Sensitivity : 110 dB SPL min. (0dB = 20µPa)
•
Frequency response compatible with the GSM specifications
For possible references, see chapter § 4.4.