
MC13109
7
MOTOROLA ANALOG IC DEVICE DATA
ELECTRICAL CHARACTERISTICS
(continued)
Pre–Amplifier/Expander/Rx Mute/Volume Control
(See Figure 4)
The Pre–Amplifier is an inverting rail–to–rail output swing
operational amplifier with the non–inverting input terminal
connected to the internal VB half supply reference. External
resistors and capacitors can be connected to set the gain and
frequency response. The expander analog ground is set to
the half supply reference so the input and output swing
capability will increase as the supply voltage increases. The
volume control can be adjusted through the MPU interface.
The “Rx Audio In” input signal is ac coupled.
(Test Conditions: VCC = 2.6 V, TA = 25
°
C, fin = 1.0 kHz, Set External Pre–Amplifier R’s for Gain of 1, Volume Control = (0111).)
Input
Pin
Characteristic
Condition
Measure
Pin
Symbol
Min
Typ
Max
Unit
Pre–Amp Open Loop
Gain
–
Rx Audio
In
Pre–Amp
AVOL
–
60
–
dB
Pre–Amp Gain
Bandwidth
–
Rx Audio
In
Pre–Amp
GBW
–
100
–
kHz
Pre–Amp Maximum
Output Swing
RL = 10 k
Rx Audio
In
Pre–Amp
VOmax
–
VCC – 0.3
–
Vpp
Expander 0 dB Gain
Level
Vin = –10 dBV
Rx Audio
In
E Out
G
–3.0
–0.11
3.0
dB
Expander Gain
Tracking
Vin = –20 dBV, Output
Relative to G
30 dBV O
Vin = –30 dBV, Output
Relative to G
Rx Audio
In
E Out
Gt
–21
–19.65
39 42
–39.42
–19
dB
–42
–37
Total Harmonic
Distortion
Vin = –10 dBV
Rx Audio
In
E Out
THD
–
0.5
–
%
Maximum Output
Voltage
Increase input voltage
until output voltage
THD = 5%, then
measure output
voltage. RL = 10 k
Ecap = 1.0
μ
F,
Rfilt = 20 k
(See Appendix B)
Rx Audio
In
E Out
VOmax
–
–5.0
–
dBV
Attack Time
Rx Audio
In
E Out
ta
–
3.0
–
ms
Release Time
Ecap = 1.0
μ
F,
Rfilt = 20 k
(See Appendix B)
Rx Audio
In
E Out
tr
–
13.5
–
ms
Compressor to
Expander Crosstalk
V (Rx Audio In)
= 0 Vrms,
Vin = –10 dBV
C In
E Out
CT
–
–
–70
dB
Rx Mute
Vin = –10 dBV
No popping
detectable during Rx
Mute transitions
Rx Audio
In
E Out
Me
–
–70
–
dB
Volume Control Range
Programmable through
MPU Interface
–
–
VCrange
–14
–
16
dB
Volume Control Steps
Programmable through
MPU Interface
–
–
VCn
–
16
–
–