MCF51QM128VHS FREESCALE [Freescale Semiconductor, Inc], MCF51QM128VHS Datasheet - Page 38

• Manufacturer Part Number: MCF51QM128VHS
• Description: MCF51QM128
• Manufacturer: FREESCALE [Freescale Semiconductor, Inc]

Analog
1. Typical values assume V
2. DC potential difference.
3. This resistance is external to MCU. The analog source resistance should be kept as low as possible in order to achieve the
4. To use the maximum ADC conversion clock frequency, the ADHSC bit should be set and the ADLPC bit should be clear.
5. For guidelines and examples of conversion rate calculation, download the ADC calculator tool: http://cache.freescale.com/
38
Symbol
reference only and are not tested in production.
best results. The results in this datasheet were derived from a system which has <8 Ω analog source resistance. The R
C
files/soft_dev_tools/software/app_software/converters/ADC_CALCULATOR_CNV.zip?fpsp=1
C
C
AS
rate
rate
time constant should be kept to <1ns.
V
AS
ADC conversion
rate
ADC conversion
rate
Description
Table 23. 16-bit ADC operating conditions (continued)
R
AS
Figure 9. ADC input impedance equivalency diagram
DDA
≤ 13 bit modes
No ADC hardware
averaging
Continuous
conversions enabled,
subsequent conversion
time
16 bit modes
No ADC hardware
averaging
Continuous
conversions enabled,
subsequent conversion
time
Conditions
= 3.0 V, Temp = 25°C, f
C
AS
Z
AS
MCF51QM128 Data Sheet, Rev. 6, 01/2012.
V
ADIN
INPUT PIN EQUIVALENT
Pad
leakage
due to
input
protection
ADCK
INPUT PIN
INPUT PIN
INPUT PIN
INPUT PIN
SIMPLIFIED
20.000
37.037
CIRCUIT
Min.
= 1.0 MHz unless otherwise stated. Typical values are for
Typ.
—
—
1
Z
ADIN
818.330
461.467
CHANNEL SELECT
Max.
R
R
R
R
ADIN
ADIN
ADIN
ADIN
SIMPLIFIED
CIRCUIT
Freescale Semiconductor, Inc.
Ksps
Ksps
Unit
C
ADIN
ADC SAR
ENGINE
Notes
5
5
AS
/