PCA9691BS/1 NXP Semiconductors, PCA9691BS/1 Datasheet - Page 8

• Manufacturer Part Number: PCA9691BS/1
• Description: IC, ADC/DAC, 8-BIT, I2C, 16-HVQFN
• Manufacturer: NXP Semiconductors

Specifications of PCA9691BS/1

• Brief Features: 8bit Successive Approximation A/D Conversion, Low Standby Current
• Supply Voltage Range: 2.5V To 5.5V
• Operating Temperature Range: -40°C To +85°C
• Digital Ic Case Style: VQFN
• No. Of: RoHS Compliant
• Ic Function: 8-bit A/D & D/A Converter
• Rohs Compliant: Yes

NXP Semiconductors
PCA9691_2
Product data sheet
7.3 D/A conversion
The third byte sent to a PCA9691 is stored in the DAC data register and is converted to
the corresponding analog voltage using the on-chip DAC. This DAC consists of a resistor
divider chain connected to the external reference voltage (pin VREF) with 256 taps and
selection switches. The tap-decoder switches one of these taps to the DAC output line
(see
The analog output voltage is buffered by an auto-zeroed unity gain amplifier. Setting the
analog output enable flag of the control register switches this buffer amplifier on or off. In
the active state the output voltage is held until a further data byte is sent.
Fig 6.
Figure
MSB
Control byte
0
7).
X
X
X
Rev. 02 — 27 January 2010
0
X
X
LSB
X
CONTROL BYTE
A/D CHANNEL NUMBER:
00 channel 0
01 channel 1
10 channel 2
11 channel 3
AUTO-INCREMENT FLAG:
active if 1
INTERNAL OSCILLATOR
FREQUENCY:
00 full oscillator frequency OSC output disabled
01 full oscillator frequency OSC enabled with 1/4 frequency
10 reserved
11 1/2 oscillator frequency OSC output disabled
ANALOG INPUT PROGRAMMING:
00 four single-ended inputs
01 three differential inputs
10 single-ended and differential mixed
11 two differential inputs
ANALOG OUTPUT ENABLE FLAG:
analog output active if 1
AIN0 channel 0
AIN1 channel 1
AIN2 channel 2
AIN3 channel 3
AIN0
AIN1
AIN2
AIN3
AIN0 channel 0
AIN1 channel 1
AIN2
AIN3
AIN0
AIN1
AIN2
AIN3
channel 0
channel 1
channel 2
channel 2
channel 0
channel 1
8-bit A/D and D/A converter
001aag466
PCA9691
© NXP B.V. 2010. All rights reserved.
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