K20P120M100SF2 Datasheet, PDF (44/66 Pages) Freescale Semiconductor, Inc – K20 Data Sheet

Peripheral operating requirements and behaviors
Table 30. 16-bit ADC with PGA characteristics (continued)
Symbol
ENOB
Description
Effective number
of bits
Conditions
• Gain=1, Average=4
• Gain=64, Average=4
• Gain=1, Average=32
• Gain=2, Average=32
• Gain=4, Average=32
• Gain=8, Average=32
• Gain=16, Average=32
• Gain=32, Average=32
• Gain=64, Average=32
Min.
11.6
7.2
12.8
11.0
7.9
7.3
6.8
6.8
7.5
Typ.¹
13.4
9.6
14.5
14.3
13.8
13.1
12.5
11.5
10.6
Max.
—
—
—
—
—
—
—
—
—
Unit
Notes
bits
16-bit
bits
differential
mode,f_in=100Hz
bits
bits
bits
bits
bits
bits
bits
SINAD
Signal-to-noise
plus distortion
ratio
See ENOB
6.02 × ENOB + 1.76
dB
1. Typical values assume V_DDA =3.0V, Temp=25°C, f_ADCK=6MHz unless otherwise stated.
2. This current is a PGA module adder, in addition to ADC conversion currents.
3. Between IN+ and IN-. The PGA draws a DC current from the input terminals. The magnitude of the DC current is a strong
function of input common mode voltage (V_CM) and the PGA gain.
4. Gain = 2^PGAG
5. After changing the PGA gain setting, a minimum of 2 ADC+PGA conversions should be ignored.
6. Limit the input signal swing so that the PGA does not saturate during operation. Input signal swing is dependent on the
PGA reference voltage and gain setting.
6.6.2 CMP and 6-bit DAC electrical specifications
Table 31. Comparator and 6-bit DAC electrical specifications
Symbol Description
Min.
Typ.
Max.
Unit
V_DD
Supply voltage
1.71
—
I_DDHS Supply current, High-speed mode (EN=1, PMODE=1)
—
—
I_DDLS Supply current, low-speed mode (EN=1, PMODE=0)
—
—
V_AIN
Analog input voltage
V_SS – 0.3
—
V_AIO
V_H
Analog input offset voltage
Analog comparator hysteresis¹
—
—
• CR0[HYSTCTR] = 00
—
5
3.6
V
200
μA
20
μA
V_DD
V
20
mV
—
mV
• CR0[HYSTCTR] = 01
—
10
—
mV
• CR0[HYSTCTR] = 10
—
20
—
mV
• CR0[HYSTCTR] = 11
—
30
—
mV
V_CMPOh
V_CMPOl
t_DHS
Output high
Output low
Propagation delay, high-speed mode (EN=1,
PMODE=1)
V_DD – 0.5
—
—
V
—
—
0.5
V
20
50
200
ns
Table continues on the next page...
K20 Data Sheet Data Sheet, Rev. 6.1, 08/2012.
44
Freescale Semiconductor, Inc.