Information

PIC16C773
DS80061C-page 12  2001 Microchip Technology Inc.
TABLE 7: MAXIMUM DEVICE FREQUENCY vs. A/D CLOCK SOURCE
ADCS<1:0>
A/D Clock Source (T
AD)
Maximum Device
Frequency
When A/D Reference is
selected as External Reference
or Analog Supply
T
AD ≥ 1.6 µs
When A/D Reference is
selected as Internal
VRH or VRL
TAD ≥ 12.8 µs
00
2 TOSC 16 TOSC 1.25 MHz
01
8 TOSC 64 TOSC 5 MHz
10
32 TOSC 256 TOSC 20 MHz
11
A/D RC A/D RC —
(1,3)
Note 1: The A/D RC source has a typical TAD time of 4 µs for VDD > 3.0V, but can vary between 2 µs and 6 µs.
2: The A/D RC source has a typical T
AD time of 32 µs for VDD > 3.0V, but can vary between 16 µs and 48 µs.
3: When the device frequency is greater than 1 MHz, the A/D RC clock source is only recommended if the
conversion will be performed during SLEEP.