ST92F120V1Q7 STMicroelectronics, ST92F120V1Q7 Datasheet - Page 279

• Manufacturer Part Number: ST92F120V1Q7
• Description: Microcontrollers (MCU) Flash 128K SPI/I2C
• Manufacturer: STMicroelectronics

Specifications of ST92F120V1Q7

• Data Bus Width: 8 bit, 16 bit
• Program Memory Type: Flash
• Program Memory Size: 128 KB
• Data Ram Size: 4 KB
• Interface Type: I2C, SPI
• Maximum Clock Frequency: 24 MHz
• Number Of Programmable I/os: 77
• Number Of Timers: 5
• Maximum Operating Temperature: + 105 C
• Mounting Style: SMD/SMT
• Package / Case: PQFP-100
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8 bit, 16 Channel
• Lead Free Status / Rohs Status: No

10.9 EIGHT-CHANNEL ANALOG TO DIGITAL CONVERTER (A/D)
10.9.1 Introduction
The 8-Channel Analog to Digital Converter (A/D)
comprises an input multiplex channel selector
feeding a successive approximation converter.
Conversion requires 138 INTCLK cycles (of which
84 are required for sampling), conversion time is
thus a function of the INTCLK frequency; for in-
stance, for a 20MHz clock rate, conversion of the
selected channel requires 6.9 s. This time in-
cludes the 4.2 s required by the built-in Sample
and Hold circuitry, which minimizes the need for
external components and allows quick sampling of
the signal to minimise warping and conversion er-
ror. Conversion resolution is 8 bits, with ±1 LSB
maximum error in the input range between V
and the analog V
The converter uses a fully differential analog input
configuration for the best noise immunity and pre-
cision performance. Two separate supply refer-
ences are provided to ensure the best possible
Figure 121. Block Diagram
n
EXTERNAL
INTERNAL
TRIGGER
TRIGGER
CONTROL REG.
DD
CONTROL
LOGIC
reference.
EIGHT-CHANNEL ANALOG TO DIGITAL CONVERTER (A/D)
DATA REGISTER 5
DATA REGISTER 4
DATA REGISTER 3
DATA REGISTER 2
DATA REGISTER 0
DATA REGISTER 7
DATA REGISTER 6
DATA REGISTER 1
COMPARE LOGIC
INTERRUPT UNIT
SS
supply noise rejection. In fact, the converted digital
value, is referred to the analog reference voltage
which determines the full scale converted value.
Naturally , Analog and Digital V
mon. If analog supplies are not present, input ref-
erence voltages are referred to the digital ground
and supply.
Up to 8 multiplexed Analog Inputs are available,
depending on the specific device type. A group of
signals can be converted sequentially by simply
programming the starting address of the first ana-
log channel to be converted and with the AUTO-
SCAN feature.
Two Analog Watchdogs are provided, allowing
continuous hardware monitoring of two input chan-
nels. An Interrupt request is generated whenever
the converted value of either of these two analog
inputs is outside the upper or lower programmed
threshold values. The comparison result is stored
in a dedicated register.
SUCCESSIVE APPROXIMATION
AUTOSCAN LOGIC
CONVERSION
A/D CONVERTER
RESULT
COMPARE RESULT REGISTER
THRESHOLD REGISTER
THRESHOLD REGISTER
THRESHOLD REGISTER
THRESHOLD REGISTER
INT. CONTROL REGISTER
INT. VECTOR POINTER
ANALOG
SS
MUX
7U
7L
6U
6L
MUST be com-
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