Microchip Technology MA240029 データシート
2010-2011 Microchip Technology Inc.
DS39996F-page 311
PIC24FJ128GA310 FAMILY
FIGURE 24-3:
10-BIT A/D CONVERTER ANALOG INPUT MODEL
EQUATION 24-1:
A/D CONVERSION CLOCK PERIOD
C
PIN
VA
Rs
ANx
I
LEAKAGE
R
IC
250
Sampling
Switch
R
SS
C
HOLD
V
SS
= 4.4 pF
500 nA
Legend:
C
PIN
V
T
I
LEAKAGE
R
IC
R
SS
C
HOLD
= Input Capacitance
= Threshold Voltage
= Leakage Current at the pin due to
= Threshold Voltage
= Leakage Current at the pin due to
= Interconnect Resistance
= Sampling Switch Resistance
= Sample/Hold Capacitance (from DAC)
= Sampling Switch Resistance
= Sample/Hold Capacitance (from DAC)
various junctions
Note:
The C
PIN
value depends on the device package and is not tested. The effect of C
PIN
is negligible if Rs
5 k.
R
SS
3 k
T
CY
(ADCS + 1)
ADCS =
– 1
T
AD
T
CY
Note:
Based on T
CY
= 2/F
OSC
; Doze mode and PLL are disabled.
T
AD
=