PCD6001 Datasheet, PDF (72/96 Pages) NXP Semiconductors – Digital telephone answering machine chip

Philips Semiconductors
Digital telephone answering machine chip
Product specification
PCD6001
16.1.3 GENERAL PURPOSE DAC
The on-chip DAC is a single channel 8-bit converter. The control of this converter is done via the GPDAR register. The
value written in this register triggers the conversion which will be present at the output pin after the digital-to-analog
conversion cycle (<25 µs). The range from the digital-to-analog output is 0 to 2000 mV (V_REF).
The conversion principle for both analog-to-digital and digital-to-analog conversion is shown in Fig.34.
16.1.3.1 General Purpose DAC Register (GPDAR)
Table 67 General Purpose DC A Register (SFR address C4H); reset state 80H
7
D/A.7
6
D/A.6
5
D/A.5
4
D/A.4
3
D/A.3
2
D/A.2
1
D/A.1
0
D/A.0
handbook, full pagewidth
VBGP
RDAC
AVS
VACM
VADC
SYMOD.4 (MIC supply bit)
VMIC
Vref
DAOUT
AAD
GPADC
(channel
request bit)
AD0IN
AD1IN
DCA VREFR
GPADC
GPDAR
GPADR
MGM796
Fig.33 The architecture of the auxiliary DAC and ADC.
handbook, full pagewidth
GPADC SFR
has been changed
by the microcontroller
HW resets request bit.
Conversion finished.
Result in GPADR SFR
GPADC SFR
has been changed
by the micro
pin GPDAR
represents output
conversion cycle (<30 µs)
analog-to-digital conversion
conversion cycle (<10 µs)
digital-to-analog conversion
time
MGM797
2001 Apr 17
Fig.34 Analog-to-digital and digital-to-analog conversion principle.
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