MAC7101MAG40 Freescale Semiconductor, MAC7101MAG40 Datasheet - Page 25

• Manufacturer Part Number: MAC7101MAG40
• Description: IC MCU 32BIT FLASH 144-LQFP
• Manufacturer: Freescale Semiconductor
• Series: MAC7xxxr

Specifications of MAC7101MAG40

• Core Processor: ARM7
• Core Size: 32-Bit
• Speed: 40MHz
• Connectivity: CAN, I²C, SCI, SPI
• Peripherals: DMA, POR
• Number Of I /o: 112
• Program Memory Size: 544KB (544K x 8)
• Program Memory Type: FLASH
• Ram Size: 32K x 8
• Voltage - Supply (vcc/vdd): 2.35 V ~ 5.5 V
• Data Converters: A/D 32x8/10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 144-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -

3.10.1 Factors Influencing Accuracy
Three factors—source resistance, source capacitance and current injection—have an influence on the
accuracy of the ATD.
3.10.1.1 Source Resistance
Due to the input pin leakage current as specified in
will be a voltage drop from the signal source to the ATD input. The maximum specified source resistance
R
operating conditions are less than the worst case, or leakage-induced errors are acceptable, larger values
of source resistance are allowed.
3.10.1.2 Source Capacitance
When sampling, an additional internal capacitor is switched to the input. This can cause a voltage drop due
to charge sharing with the external capacitance and the pin capacitance. For a maximum sampling error of
the input voltage ≤ 1 LSB, then the external filter capacitor must be calculated as, C
3.10.1.3 Current Injection
There are two cases to consider:
Freescale Semiconductor
S
, results in an error of less than 1/2 LSB (2.5 mV) at the maximum leakage current. If the device or
1. A current is injected into the channel being converted. The channel being stressed has conversion
2. Current is injected into pins in the neighborhood of the channel being converted. A portion of this
Conditions are shown in
Num C
Q1
Q2
Q3
Q4
Q5
values of 0x3FF (0xFF in 8-bit mode) for analog inputs greater than V
than V
current is picked up by the channel (coupling ratio K), This additional current impacts the
accuracy of the conversion depending on the source resistance. The additional input voltage error
on the converted channel can be calculated as V
the currents injected into the two pins adjacent to the converted channel.
C Max input Source Resistance
C Total Input Capacitance
C Disruptive Analog Input Current
C Coupling Ratio positive current injection
C Coupling Ratio negative current injection
Non Sampling
Sampling
RL
unless the current is higher than specified as disruptive condition.
MAC7100 Microcontroller Family Hardware Specifications, Rev. 1.2
Table 7
Rating
unless otherwise noted
Table 28. ATD Electrical Characteristics
Preliminary
Table 8
Symbol
ERR
C
C
I
R
K
K
NA
INN
INS
in conjunction with the source resistance there
S
p
n
= K
×
R
–2.5
Min
—
—
—
—
—
S ×
I
INJ
, with I
RH
Typ
—
10
22
—
—
—
and 0x000 for values less
f
INJ
Electrical Characteristics
≥ 1024
being the sum of
Max
TBD
TBD
2.5
—
—
1
×
(C
INS
A / A
A / A
Unit
mA
kΩ
pF
pF
– C
INN
25
).