MAX1102 Datasheet, PDF (12/16 Pages) Maxim Integrated Products – 8-Bit CODECs

8-Bit CODECs
Both the ADC and DAC can be addressed from the
same control word, allowing both converters to operate
simultaneously.
Configuring the ADC
When configuring the ADC immediately following
power-up, the first control word enables the ADC and
sets the T/H to track mode. Then wait 200µs for the
internal reference to stablize (3µs typical from standby
mode). Finally, the second control word sets the ADC
into either single or continuous mode and causes con-
version to take place.
Conversion Modes
The MAX1102/MAX1103/MAX1104 have two conver-
sion modes, single and continuous.
In single conversion mode (C0 = 0), a control word
must be written before an ADC conversion result can
be read, or DAC input data is accepted. Once a con-
version has occurred, the device will ignore any input
until a new control word is written. Figures 5 and 6
show the DAC and ADC single conversion mode timing
diagrams.
In continuous conversion mode (C0 = 1), the device
maintains its configuration from a single control word,
and continuously updates the ADC conversion result,
or accepts new DAC input data.
When operating the ADC and DAC simultaneously,
both converters must be in the same conversion mode.
ADC Single Conversion Mode
Set C0 = 0 to select single conversion mode. The
falling edge of SCLK after the eighth bit of each control
word causes the ADC to switch from track to hold
mode and begin conversion. To avoid corruption of the
conversion result, SCLK must be disabled for 36µs
(Figure 6). After completing the conversion, the ADC
CS
SCLK
DIN
DAC
S ADDR
DAC ON
DAC
DATA
DAC
S ADDR
DAC ON
DAC
DATA
DAC
S ADDR
DAC ON
DAC
DATA
DAC
S ADDR
DAC OFF
DAC
DATA
DAC
S ADDR
DAC ON
DAC
DATA
OUT
NOTE: "S" DENOTES THE BEGINNING OF A CONTROL WORD
Figure 5. DAC Single Conversion Mode Timing Diagram
CS
SCLK
DIN
S
ADC
ON
ADC
S ADDR
ADC ON
ADC
S ADDR
ADC ON
ADC
S ADDR
ADC OFF
tCONV
tCONV
1
AIN
2
ACQUISITION MODE
ACQUISITION MODE
DOUT
MSB LSB
CONVERSION
RESULT FOR 1
Figure 6. ADC Single Conversion Mode Timing Diagram
MSB LSB
CONVERSION
RESULT FOR 2
S
ADC
ON
ADC
ADC
S ADDR S ADDR
ADC ON ADC ON
3
4
ACQUISITION
MODE
MSB LSB MSB LSB
CONVERSION CONVERSION
RESULT FOR 3 RESULT FOR 4
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