DSB75 Development Support Board Rev. B1 Hardware Description
Confidential / Released
DSB75_hd_v12
Page 83 of 96
2008-08-26
Parameters
Condition
Min.
Typical
Max.
Unit
Differential output
voltage at full scale sine
1kHz
1.6
Vpp
Audio interface 1
(balanced input)
Handset Mode
(AT^SNFS=1)
Differential input
voltage for 0dBm0
(after settling)
30
mV
Maximum differential
output voltage, no load
6.0
Vpp
Differential output
resistance
15
Ω
Differential output load
0
Ω
Differential input
voltage
1.6
V
Input impedance
4.0
k
Ω
Microphone supply
voltage
5.0
V
Audio interface 1
(balanced input)
General Information
Microphone supply DC
resistance
4.6
k
Ω
Output voltage
3.4
Vpp
Differential output
resistance
15
Ω
Differential output load
16
Ω
Input voltage
1.6
V
Input impedance
2.0
k
Ω
Microphone supply
voltage
2.5
V
Audio interface 2
(single ended input)
General Information
Microphone supply DC
resistance
2.2
k
Ω
SPI interface
Digital audio interface
SIM interface
USB interface
SD card interface
The interface lines are
connected directly to
the GSM module
See module specification [1] for details.
Ignition (Key)
Emergency Restart
(Key)
Ignition via DTR line
@COM1
V
I
= ±3V…±9V:
V
I
>±9V:
signal
~~~
|________|
~~~~~~~~~~~~~~~
signal
~~~
|________|
~~~~~~~~~~~~~~~
|
≥
1s |
≥
0.5s |
|
≥
0.5s |
≥
0.5s |
Rise time
≤
1ms.
Low high transition of this signal switches the module on.
