st2032a Sitronix Technology Corporation, st2032a Datasheet - Page 31

• Manufacturer Part Number: st2032a
• Description: 8 Bit Microcontroller With 32k Bytes Rom
• Manufacturer: Sitronix Technology Corporation

14.3.2 Two-Pin Two Ended Mode (8-bit Accuracy)
Two-Pin Two-Ended mode is designed for use with a single
transistor amplifier. It requires two pin that PSGO and
PSGOB. When the DAC value is positive, PSGO goes high
with a duty cycle proportional to the output value, while
PSGOB stays high. When the DAC value is negative,
PSGOB goes low with a duty cycle proportional to the
output value, while PSGO stays low. This mode offers a
resolution of 8 bits.
Ver 2.4
PSGOB
PSGOB
PSGO
PSGO
High
High
High
High
Low
Low
Low
Low
Where X=0 to -128
Where X=0 to 127
|X|
X
DAC = X
DAC = X
FIGURE 14-6 Two-Pin Two Ended Mode Application Circuit
128+X
128-X
FIGURE 14-5 Two-Pin Two Ended Mode Wave-Form
ST2032A
PSGOB
PSGO
32
DAC = -48
48
DAC = 32
2.8K
2.5K
96
80
vdd
31/54
Figure 13-5 shows examples of DAC output waveforms with
different output values. Each pulse of the DAC is divided
into 128 segments per sample period. For a positive output
value x=0 to 127, PSGO goes high for X segments while
PSGOB stays high. For a negative output value x=0 to -127,
PSGOB goes low for |X| segments while PSGO stays low.
8050
SPK
DAC = 96
DAC = 0
96
4.7uf
32
DAC = 127
DAC = -128
127
1
ST2032A
9/13/07