Marine VHF Audio and Signalling Processor
CMX885
AC Parameters (continued)
Notes
Min.
Typ.
Max.
Unit
XTAL/CLK Input
‘High’ Pulse Width
‘Low’ Pulse Width
31
31
15
15
–
–
–
–
ns
ns
Input Impedance (measured at 6.144MHz)
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Resistance
Capacitance
Resistance
Capacitance
–
–
–
–
–
150
20
300
20
400
–
–
–
–
–
kΩ
pF
kΩ
pF
ms
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Xtal Start Up (from powersave)
VBIAS
Start up time (from powersave)
–
30
–
ms
Microphone, Alternative and Discriminator
Inputs
(MICN, ALTN, DISCN)
Input impedance
34
35
–
–
80
1
–
–
–
80%
–
MΩ
AVDD
kΩ
Maximum Input Level (pk-pk)
Load Resistance (feedback pins)
Amplifier Open Loop Voltage Gain
(I/P = 1mV rms at 100Hz)
Unity Gain Bandwidth
⎫
⎭
–
–
60
1.0
–
–
dB
MHz
36
37
Programmable Input Gain Stage
Gain (at 0dB)
Cumulative Gain Error
0
0
+0.5
+1.0
dB
dB
−0.5
−1.0
⎫
⎭
(wrt attenuation at 0dB)
37
31
34
35
Timing for an external input to the XTAL/CLK pin.
With no external components connected.
Centred about AVDD/2; after multiplying by the gain of input circuit (with external
components connected).
Notes:
36
37
Gain applied to signal at output of buffer amplifier: DISCFB, ALTFB OR MICFB
Design value for this block only in test mode. Overall attenuation input to output
has a tolerance of 0dB ±1.0dB.
© 2010 CML Microsystems Plc
62
D/885/3
CMLMICRO [ CML MICROCIRCUITS ]
