MC68HC05B6_13 Datasheet, PDF (242/302 Pages) Freescale Semiconductor, Inc – Microcontrollers

Table F-10 A/D characteristics for 3.3V operation
(V_DD = 3.3 Vdc ± 10%, V_SS = 0 Vdc, T_A = T_L to T_H)
Characteristic
Parameter
Min
Max
Unit
Resolution
Number of bits resolved by the A/D
8
—
Bit
Non-linearity
Quantization error
Max deviation from the best straight line through the A/D
transfer characteristics
—
(V_RH = V_DD and V_RL = 0V)
Uncertainty due to converter resolution
—
±1
LSB
±1
LSB
Absolute accuracy
Difference between the actual input voltage and the
full-scale equivalent of the binary code output code for all
—
errors
±2
LSB
Conversion range
V_RH
V_RL
∆V_R
Conversion time
Analog input voltage range
V_RL
V_RH
V
Maximum analog reference voltage
V_RL
V_DD + 0.1
V
Minimum analog reference voltage
V_SS – 0.1
V_RH
V
Minimum difference between V_RH and V_RL
3
—
V
Total time to perform a single analog to digital conversion
Internal RC oscillator
—
32
µs
Monotonicity
Conversion result never decreases with an increase in
input voltage and has no missing codes
GUARANTEED
Zero input reading
Full scale reading
Sample acquisition time
Conversion result when V_IN = V_RL
Conversion result when V_IN = V_RH
Analog input acquisition sampling
Internal RC oscillator⁽¹⁾
00
—
Hex
—
FF
Hex
—
12
µs
Sample/hold capacitance Input capacitance on PD0/AN0–PD7/AN7
—
Input leakage⁽²⁾
Input leakage on A/D pins PD0/AN0–PD7/AN7, VRL, VRH —
12
pF
1
µA
(1) Source impedances greater than 10kΩ will adversely affect internal charging time during input sampling.
(2) The external system error caused by input leakage current is approximately equal to the product of R source and input
current. Input current to A/D channel will be dependent on external source impedance (see Figure 8-2).
14
Freescale
F-24
MC68HC705B16N
MC68HC05B6
Rev. 4.1