ST92T141K4M6 STMicroelectronics, ST92T141K4M6 Datasheet - Page 147

• Manufacturer Part Number: ST92T141K4M6
• Description: Microcontrollers (MCU) OTP EPROM 16K SPI
• Manufacturer: STMicroelectronics

Specifications of ST92T141K4M6

• Data Bus Width: 8 bit, 16 bit
• Program Memory Type: EPROM
• Program Memory Size: 16 KB
• Data Ram Size: 512 B
• Interface Type: SPI
• Maximum Clock Frequency: 25 MHz
• Number Of Programmable I/os: 15
• Number Of Timers: 2
• Operating Supply Voltage: 4.5 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• Package / Case: SO-34
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 8 bit, 6 Channel
• Lead Free Status / Rohs Status: No

7.6 ANALOG TO DIGITAL CONVERTER (ADC)
Important Note: This chapter is a generic descrip-
tion of the ADC peripheral. However depending on
the ST9 device, some or all of the interface signals
described may not be connected to external pins.
For the list of ADC pins present on the ST9 device,
refer to the device pinout description in the first
section of the data sheet.
7.6.1 Introduction
The Analog to Digital Converter (ADC) comprises
an input multiplex channel selector feeding a suc-
cessive approximation converter.
The conversion time depends on the INTCLK fre-
quency and the prescaler factor stored in the
PR[2:0] bits of the CRR register (R252).
The minimum conversion time is 138 INTCLK and
with the maximum prescaling factor it becomes
about 16 times longer.
For instance, with INTCLK at 20 MHz and PR[2:0]
equal to "111", conversion of the selected channel
requires 6.9µs.
equals "110" and so on. Refer to
list of conversion and sampling times.
The 6.9µs time includes the 4 s required by the
built-in Sample and Hold circuitry, which minimiz-
es the need for external components and allows
quick sampling of the signal to minimise warping
and conversion error.
Figure 78. Block Diagram
EXTERNAL
INTERNAL
TRIGGER
TRIGGER
CONTROL REG.
It requires 27.45µs if PR[2:0]
CONTROL
LOGIC
Table 30
DATA REGISTER 5
DATA REGISTER 4
DATA REGISTER 3
DATA REGISTER 2
DATA REGISTER 0
DATA REGISTER 7
DATA REGISTER 6
DATA REGISTER 1
ST92141 - ANALOG TO DIGITAL CONVERTER (ADC)
COMPARE LOGIC
for the
INTERRUPT UNIT
Conversion resolution is 8 bits, with ±1 LSB maxi-
mum error in the input range between V
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
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
DD
reference.
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-
SS
VA00223
and the
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