S912XEP768J5MAGR Freescale Semiconductor, S912XEP768J5MAGR Datasheet - Page 523

• Manufacturer Part Number: S912XEP768J5MAGR
• Description: 16-bit Microcontrollers - MCU 16-bit 768K Flash
• Manufacturer: Freescale Semiconductor

Specifications of S912XEP768J5MAGR

• Rohs: yes
• Core: HCS12X
• Processor Series: MC9S12
• Data Bus Width: 16 bit
• Maximum Clock Frequency: 50 MHz
• Program Memory Size: 768 KB
• Data Ram Size: 48 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 3.3 V to 5 V
• Operating Temperature Range: - 40 C to + 125 C
• Package / Case: LQFP-144
• Mounting Style: SMD/SMT

13.4
The ADC12B16C is structured into an analog sub-block and a digital sub-block.
13.4.1
The analog sub-block contains all analog electronics required to perform a single conversion. Separate
power supplies V
13.4.1.1
The Sample and Hold (S/H) Machine accepts analog signals from the external world and stores them as
capacitor charge on a storage node.
During the sample process the analog input connects directly to the storage node.
The input analog signals are unipolar and must fall within the potential range of V
During the hold process the analog input is disconnected from the storage node.
13.4.1.2
The analog input multiplexer connects one of the 16 external analog input channels to the sample and hold
machine.
13.4.1.3
The A/D Machine performs analog to digital conversions. The resolution is program selectable at either 8
or 10 or 12 bits. The A/D machine uses a successive approximation architecture. It functions by comparing
the stored analog sample potential with a series of digitally generated analog potentials. By following a
binary search algorithm, the A/D machine locates the approximating potential that is nearest to the
sampled potential.
When not converting the A/D machine is automatically powered down.
Freescale Semiconductor
Functional Description
Analog Sub-Block
Sample and Hold Machine
Analog Input Multiplexer
Analog-to-Digital (A/D) Machine
DDA
and V
Table 13-22. Conversion result mapping to ATDDRn
SSA
resolution
MC9S12XE-Family Reference Manual Rev. 1.25
10-bit data
10-bit data
12-bit data
8-bit data
8-bit data
allow to isolate noise of other MCU circuitry from the analog sub-block.
A/D
0
1
0
1
X
DJM
conversion result mapping to
Bit[11:4] = result, Bit[3:0]=0000
Bit[7:0] = result, Bit[11:8]=0000
Bit[11:2] = result, Bit[1:0]=00
Bit[9:0] = result, Bit[11:10]=00
Bit[11:0] = result
ATDDRn
Chapter 13 Analog-to-Digital Converter (ADC12B16CV1)
SSA
to V
DDA
.
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