Datasheet

PIC16F88X
DS80000302H-page 14  2007-2013 Microchip Technology Inc.
Data Sheet Clarifications
The following typographic corrections and clarifications
are to be noted for the latest version of the device data
sheet (DS41291G):
1. Module: ADC (Block Diagram)
Figure 9-1: ADC Block Diagram changes
references from AV
SS to VSS and AVDD to VDD.
2. Module: ADC
Acquisition Time Example calculation correction.
EQUATION 9-1: ACQUISITION TIME EXAMPLE
Note: Corrections are shown in bold. Where
possible, the original bold text formatting
has been removed for clarity.
TACQ Amplifier Settling Time Hold Capacitor Charging Time Temperature Coefficient++=
T
AMP TC TCOFF++=
2µs T
C Temperature - 25°C0.05µs/°C++=
TC CHOLD RIC RSS RS++ ln(1/2047)–=
10pF 1k
 7k  10k  ++– ln(0.0004885)=
1.37
= µs
T
ACQ 2µs 1.37µs 50°C- 25°C0.05µs/°C++=
4.67µs=
VAPPLIED 1e
Tc–
RC
---------
–



VAPPLIED 1
1
2
n1+
1–
--------------------------–


=
VAPPLIED 1
1
2
n1+
1–
--------------------------–


VCHOLD=
VAPPLIED 1e
TC–
RC
----------
–



VCHOLD=
;[1] VCHOLD charged to within 1/2 lsb
;[2] V
CHOLD charge response to VAPPLIED
;combining [1] and [2]
The value for T
C can be approximated with the following equations:
Solving for T
C:
Therefore:
Temperature 50°C and external impedance of 10k
 5.0V VDD=
Assumptions: