ST7FLITE02 STMICROELECTRONICS [STMicroelectronics], ST7FLITE02 Datasheet - Page 71

• Manufacturer Part Number: ST7FLITE02
• Description: 8-BIT MICROCONTROLLER WITH SINGLE VOLTAGE FLASH MEMORY, DATA EEPROM, ADC, TIMERS, SPI
• Manufacturer: STMICROELECTRONICS [STMicroelectronics]

11.4 8-BIT A/D CONVERTER (ADC)
11.4.1 Introduction
The on-chip Analog to Digital Converter (ADC) pe-
ripheral is a 8-bit, successive approximation con-
verter with internal sample and hold circuitry. This
peripheral has up to 5 multiplexed analog input
channels (refer to device pin out description) that
allow the peripheral to convert the analog voltage
levels from up to 5 different sources.
The result of the conversion is stored in a 8-bit
Data Register. The A/D converter is controlled
through a Control/Status Register.
11.4.2 Main Features
■
■
■
■
■
■
■
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8-bit conversion
Up to 5 channels with multiplexed input
Linear successive approximation
Dual input range
– 0 to V
– 0V to 250mV
Data register (DR) which contains the results
Conversion complete status flag
On/off bit (to reduce consumption)
Fixed gain operational amplifier (x8) (not
available on ST7LITES5 devices)
DD
or
11.4.3 Functional Description
11.4.3.1 Analog Power Supply
The block diagram is shown in
V
voltage pins.
Conversion accuracy may therefore be impacted
by voltage drops and noise in the event of heavily
loaded or badly decoupled power supply lines.
For more details, refer to the Electrical character-
istics section.
11.4.3.2 Input Voltage Amplifier
The input voltage can be amplified by a factor of 8
by enabling the AMPSEL bit in the ADAMP regis-
ter.
When the amplifier is enabled, the input range is
0V to 250 mV.
For example, if V
vert voltages in the range 0V to 250mV with an
ideal resolution of 2.4mV (equivalent to 11-bit res-
olution with reference to a V
For more details, refer to the Electrical character-
istics section.
Note: The amplifier is switched on by the ADON
bit in the ADCCSR register, so no additional start-
up time is required when the amplifier is selected
by the AMPSEL bit.
DD
and V
SS
are the high and low level reference
DD
= 5V, then the ADC can con-
ST7LITE0x, ST7LITESx
SS
Figure
to V
DD
43.
range).
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