msm7557 Oki Semiconductor, msm7557 Datasheet - Page 9
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msm7557
Manufacturer Part Number
msm7557
Description
Single Chip Msk Modem With Compandor For Cordless Telephone
Manufacturer
Oki Semiconductor
Datasheet
1.MSM7557.pdf
(25 pages)
¡ Semiconductor
(Continued)
Name
PDN
X1
X2
ME
TVE
Power down control.
Power down state is controlled by PDN, ME, RVE, and TVE.
At the mode 4, all functions are powered on.
At the full power down mode(PDN = "1" and RVE = "0"), the demodulator circuit and FD pin are reset.
When V
Crystal connection.
3.6864 MHz crystal shall be connected.
When an external master clock is applied, the clock should be supplied to X2 pin via a 200 pF capacitor for
AC coupling and X1 should be opened.
MSK moudulator output.
When digital "1" is applied to this pin, MSK modulator is connected to the splatter filter.
Refer to TAO pin description.
Transmit side voice signal contorol.
Refer to TAO pin description.
Mode1
Mode2
Mode3
Mode4
DD
is turned ON, the demodulator circuit and FD pin should be reset by setting Mode1.
PDN
1
1
0
ME
X
X
1
others
RVE
0
1
0
TVE
X
X
0
Voice control
Function
path
OFF
OFF
OFF
ON
Transmit side
modem
OFF
OFF
ON
ON
Receive side
modem
X : Don't care
OFF
ON
ON
ON
MSM7557
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