Datasheet

© 2007-2011 Microchip Technology Inc. DS70290J-page 249
dsPIC33FJ32GP202/204 and dsPIC33FJ16GP304
FIGURE 22-21: ADC CONVERSION (12-BIT MODE) TIMING CHARACTERISTICS
(ASAM = 0, SSRC<2:0> = 000)
TABLE 22-41: ADC CONVERSION (12-BIT MODE) TIMING REQUIREMENTS
AD55
TSAMP
Clear SAMPSet SAMP
AD61
ADCLK
Instruction
SAMP
AD60
DONE
AD1IF
1 2 3 4 5 6 87
1
– Software sets AD1CON. SAMP to start sampling.
2
– Sampling starts after discharge period. T
SAMP is described in
3
– Software clears AD1CON. SAMP to start conversion.
4
– Sampling ends, conversion sequence starts.
5
– Convert bit 11.
9
– One TAD for end of conversion.
AD50
9
6
– Convert bit 10.
7
– Convert bit 1.
8
– Convert bit 0.
Execution
Section 16. “Analog-to-Digital Converter (ADC)” (DS70183) in the
“dsPIC33F/PIC24H Family Reference Manual”.
AC CHARACTERISTICS
Standard Operating Conditions: 3.0V to 3.6V
(unless otherwise stated)
Operating temperature -40°C ≤ TA ≤ +85°C for Industrial
-40°C ≤ T
A ≤ +125°C for Extended
Param
No.
Symbol Characteristic Min. Typ Max. Units Conditions
Clock Parameters
AD50 TAD ADC Clock Period
(2)
117.6 — — ns —
AD51 tRC ADC Internal RC Oscillator
Period
(2)
— 250 — ns —
Conversion Rate
AD55 t
CONV Conversion Time
(2)
— 14 TAD —ns —
AD56 F
CNV Throughput Rate
(2)
——500Ksps —
AD57 T
SAMP Sample Time
(2)
3.0 TAD —— — —
Timing Parameters
AD60 t
PCS Conversion Start from Sample
Trigger
(2)
2.0 TAD — 3.0 TAD — Auto Convert Trigger
not selected
AD61 t
PSS Sample Start from Setting
Sample (SAMP) bit
(2)
2.0 TAD — 3.0 TAD ——
AD62 t
CSS Conversion Completion to
Sample Start (ASAM = 1)
(2)
— 0.5 TAD —— —
AD63 tDPU Time to Stabilize Analog Stage
from ADC Off to ADC On
(2)
——20μs—
Note 1: Because the sample caps will eventually lose charge, clock rates below 10 kHz can affect linearity
performance, especially at elevated temperatures.
2: These parameters are characterized but not tested in manufacturing.