PIC16F1946-E/PT Microchip Technology, PIC16F1946-E/PT Datasheet - Page 170

• Manufacturer Part Number: PIC16F1946-E/PT
• Description: MCU 8BIT 8K FLASH 64TQFP
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 16Fr

Specifications of PIC16F1946-E/PT

• Core Size: 8-Bit
• Program Memory Size: 14KB (8K x 14)
• Core Processor: PIC
• Speed: 32MHz
• Connectivity: I²C, LIN, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 54
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 17x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Package / Case: 64-TFQFP
• Controller Family/series: PIC16F
• Eeprom Memory Size: 256Byte
• Ram Memory Size: 512Byte
• Cpu Speed: 32MHz
• No. Of Timers: 5
• Interface: EUSART, I2C, SPI
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

PIC16F/LF1946/47
16.3
For the ADC to meet its specified accuracy, the charge
holding capacitor (C
charge to the input channel voltage level. The Analog
Input model is shown in
impedance (R
impedance directly affect the time required to charge
the capacitor C
impedance varies over the device voltage (V
to
impedance for analog sources is 10 k. As the
EQUATION 16-1:
DS41414B-page 170
The value for T
Solving for T
Therefore:
Note 1: The reference voltage (V
Assumptions:
Figure
V
V
V
Note: Where n = number of bits of the ADC.
2: The charge holding capacitor (C
3: The maximum recommended impedance for analog sources is 10 k. This is required to meet the pin
A/D Acquisition Requirements
AP P LI ED
AP P LI ED
AP P LI ED
16-4.
leakage specification.
T
S
T
A CQ
) and the internal sampling switch (R
C
ACQ
T
:
HOLD
C
C
The








Temperature
can be approximated with the following equations:
=
=
=
=
=
1
1 e
1 e
HOLD
=
=
=
. The sampling switch (R
ACQUISITION TIME EXAMPLE
–
–
–
1.12
–
4.42µs
–
2µs
Amplifier Settling Time
T
2µs
C
10pF 1k
--------------------------

maximum
AMP
) must be allowed to fully
2
–
--------- -
–
-------- -
HOLD
RC
RC
µs
T
Tc
+
n
Figure
+
C
+



1.12µs




+
1
T
1

C
 1
=
R
=
T

+
IC
C
–
16-4. The source
=
V
V
+
+

REF
+
+

A PP LIE D


CHOLD
recommended
7k
50°C and external impedance of 10k
Temperature - 25°C
T
R

) has no effect on the equation, since it cancels itself out.
COFF


=
SS
50°C- 25°C
+
+
HOLD
DD
V
10k
CHOLD
R
), refer


S
1
+
 ln(1/511)
) is not discharged after each conversion.

Preliminary
SS
SS
–
Hold Capacitor Charging Time

)
)
--------------------------

ln(0.001957)

2

0.05
n
+
 0.05µs/°C
1
µs/°C
1

 1
source impedance is decreased, the acquisition time
may be decreased. After the analog input channel is
selected (or changed), an A/D acquisition must be
done before the conversion can be started. To calculate
the minimum acquisition time,
used. This equation assumes that 1/2 LSb error is used
(1,024 steps for the ADC). The 1/2 LSb error is the
maximum error allowed for the ADC to meet its
specified resolution.
–




;[1] V
;[2] V
;combining [1] and [2]



CHOLD
CHOLD
5.0V V
+
charged to within 1/2 lsb
charge response to V
DD
Temperature Coefficient
 2010 Microchip Technology Inc.
Equation 16-1
APPLIED
may be