PIC17C752-08/CL MICROCHIP [Microchip Technology], PIC17C752-08/CL Datasheet - Page 183

• Manufacturer Part Number: PIC17C752-08/CL
• Description: High-Performance 8-Bit CMOS EPROM Microcontrollers with 10-bit A/D
• Manufacturer: MICROCHIP [Microchip Technology]

16.2
The A/D conversion time per bit is defined as T
A/D conversion requires a minimum 12T
conversion. The source of the A/D conversion clock is
software selected. The four possible options for T
are:
TABLE 16-1:
TABLE 16-2:
Operation
8T
32T
64T
RC
Legend: Shaded cells are are outside of recommended ranges.
Note 1: The RC source has a typical T
Operation
8T
32T
64T
RC
Legend: Shaded cells are are outside of recommended ranges.
Note 1: The RC source has a typical T
1998 Microchip Technology Inc.
OSC
OSC
• 8T
• 32T
• 64T
• Internal RC oscillator
OSC
OSC
OSC
OSC
2: These values violate the minimum required T
3: For faster conversion times, the selection of another clock source is recommended.
4: When the device frequencies is greater than 1 MHz, the RC A/D conversion clock source is only recom-
2: These values violate the minimum required T
3: For faster conversion times, the selection of another clock source is recommended.
4: When the device frequencies is greater than 1 MHz, the RC A/D conversion clock source is only recom-
AD Clock Source (T
AD Clock Source (T
Selecting the A/D Conversion Clock
OSC
mended for sleep operation.
mended for sleep operation.
OSC
OSC
T
T
ADCS1:ADCS0
ADCS1:ADCS0
AD
AD
vs. DEVICE OPERATING FREQUENCIES (EXTENDED VOLTAGE DEVICES (LC))
vs. DEVICE OPERATING FREQUENCIES (STANDARD DEVICES (C))
00
01
10
11
00
01
10
11
AD
AD
)
)
2 - 6 s
3 - 9 s
AD
AD
AD
242 ns
970 ns
1.0 s
33 MHz
1.94 s
8 MHz
4.0 s
8.0 s
time of 4 s.
time of 6 s.
per 10-bit
AD
(1, 4)
(1, 4)
(2)
(2)
(2)
. The
AD
AD
AD
2 - 6 s
3 - 9 s
time.
time.
400 ns
2.0 s
20 MHz
1.6 s
3.2 s
4 MHz
16 s
8 s
For correct A/D conversions, the A/D conversion clock
(T
of 1.6 s.
Table 16-1
times derived from the device operating frequencies
and the A/D clock source selected. These times are for
standard voltage range devices.
(1, 4)
(1, 4)
(2)
(2)
AD
Device Frequency
Device Frequency
) must be selected to ensure a minimum T
2 - 6 s
3 - 9 s
12.8 s
32 s
and
5 MHz
2 MHz
1.6 s
6.4 s
16 s
4 s
(1, 4)
(3)
(1, 4)
Table 16-2
(3)
PIC17C7XX
2 - 6 s
1.25 MHz
3 - 9 s
25.6 s
51.2 s
32 s
64 s
6.4 s
1 MHz
8 s
show the resultant T
(1, 4)
(3)
(3)
(3)
(3)
(1)
DS30289A-page 183
333.33 kHz
333.33 kHz
2 - 6 s
3 - 9 s
192 s
192 s
96 s
96 s
24 s
24 s
AD
(3)
(3)
(3)
(3)
(1)
(1)
time
AD