PCF8591P NXP Semiconductors, PCF8591P Datasheet - Page 7

• Manufacturer Part Number: PCF8591P
• Description: IC, A/D AND D/A CONVERTER, 8BIT, 16-DIP
• Manufacturer: NXP Semiconductors
• Type: General Purposer

Specifications of PCF8591P

• Number Of Channels: 1
• Number Of Adc's: 1
• Number Of Dac's: 1
• Adc/dac Resolution: 8b
• Interface Type: Serial (I2C)
• Operating Supply Voltage (typ): 3.3/5V
• Sample Rate: 11.1KSPS
• Number Of Adc Inputs: 4
• Number Of Dac Outputs: 1
• Operating Supply Voltage (max): 6V
• Operating Supply Voltage (min): 2.5V
• Operating Temperature (max): 85C
• Operating Temperature (min): -40C
• Pin Count: 16
• Mounting: Through Hole
• Supply Voltage Range: 2.5V To 6V
• Operating Temperature Range: -40°C To +85°C
• Digital Ic Case Style: DIP
• No. Of Pins: 16
• Linearity Error -: 1.5LSB
• Termination Type: DIP
• Supply Voltage Max: 8V
• Input Channels Per Adc: 1
• Rohs Compliant: Yes
• Filter Terminals: DIP
• Conversion Time: 90µs
• Data Interface: I2C, Serial
• Lead Free Status / RoHS Status: Compliant

Philips Semiconductors
7.3
The third byte sent to a PCF8591 device is stored in the
DAC data register and is converted to the corresponding
analog voltage using the on-chip D/A converter. This D/A
converter consists of a resistor divider chain connected to
the external reference voltage with 256 taps and selection
switches. The tap-decoder switches one of these taps to
the DAC output line (see Fig.6).
The analog output voltage is buffered by an auto-zeroed
unity gain amplifier. This buffer amplifier may be switched
on or off by setting the analog output enable flag of the
2003 Jan 27
handbook, full pagewidth
8-bit A/D and D/A converter
D/A conversion
AGND
V REF
Fig.6 DAC resistor divider chain.
R256
R255
R3
R2
R1
7
control register. In the active state the output voltage is
held until a further data byte is sent.
The on-chip D/A converter is also used for successive
approximation A/D conversion. In order to release the
DAC for an A/D conversion cycle the unity gain amplifier is
equipped with a track and hold circuit. This circuit holds the
output voltage while executing the A/D conversion.
The output voltage supplied to the analog output AOUT is
given by the formula shown in Fig.7. The waveforms of a
D/A conversion sequence are shown in Fig.8.
FF
02
01
00
DAC out
DECODER
TAP
MBL826
D7
D6
D0
Product specification
PCF8591