PIC16F77-E/PT Microchip Technology, PIC16F77-E/PT Datasheet - Page 88

• Manufacturer Part Number: PIC16F77-E/PT
• Description: IC MCU FLASH 8KX14 A/D 44TQFP
• Manufacturer: Microchip Technology
• Series: PIC® 16Fr

Specifications of PIC16F77-E/PT

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 33
• Program Memory Size: 14KB (8K x 14)
• Program Memory Type: FLASH
• Ram Size: 368 x 8
• Voltage - Supply (vcc/vdd): 4 V ~ 5.5 V
• Data Converters: A/D 8x8b
• Oscillator Type: External
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 44-TQFP, 44-VQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Other names: PIC16F77E/PT

PIC16F7X
11.1
For the A/D converter to meet its specified accuracy,
the charge holding capacitor (C
to fully charge to the input channel voltage level. The
analog input model is shown in Figure 11-2. The source
impedance (R
impedance directly affect the time required to charge
the capacitor C
impedance varies over the device voltage (V
Figure 11-2. The source impedance affects the offset
voltage at the analog input (due to pin leakage current).
FIGURE 11-2:
TABLE 11-1:
DS30325B-page 86
Note 1: The RC source has a typical T
2: When the device frequencies are greater than 1 MHz, the RC A/D conversion clock source is only
3: For extended voltage devices (LC), please refer to the Electrical Specifications section.
A/D Acquisition Requirements
recommended for SLEEP operation.
Operation
S
RC
) and the internal sampling switch (R
32T
2T
8T
HOLD
(1, 2, 3)
T
OSC
OSC
OSC
Legend C
AD
VA
. The sampling switch (R
ANALOG INPUT MODEL
vs. MAXIMUM DEVICE OPERATING FREQUENCIES (STANDARD DEVICES (C))
R
V
I leakage
R
SS
C
S
T
PIN
IC
HOLD
AD Clock Source (T
ANx
C
5 pF
HOLD
PIN
= input capacitance
= threshold voltage
= leakage current at the pin due to
= interconnect resistance
= sampling switch
= sample/hold capacitance (from DAC)
various junctions
) must be allowed
AD
time of 4 µs but can vary between 2-6 µs.
V
DD
DD
), see
V
V
AD
T
T
SS
SS
= 0.6V
= 0.6V
ADCS1:ADCS0
)
)
)
00
01
10
11
I leakage
± 500 nA
The maximum recommended impedance for ana-
log sources is 10 kΩ. After the analog input channel is
selected (changed), the acquisition period must pass
before the conversion can be started.
To calculate the minimum acquisition time, T
the PICmicro™ Mid-Range MCU Family Reference
Manual (DS33023). In general, however, given a max-
imum source impedance of 10 kΩ and at a temperature
of 100°C, T
R
IC
≤ 1k
V
SS R
DD
Sampling
Switch
ACQ
6V
5V
4V
3V
2V
will be no more than 16 µsec.
SS
Sampling Switch
5 6 7 8 9 10 11
Maximum Device Frequency
V
 2002 Microchip Technology Inc.
SS
C
= DAC Capacitance
= 51.2 pF
(k Ω )
HOLD
1.25 MHz
(Note 1)
20 MHz
5 MHz
Max.
ACQ
, see