PIC16F1937-E/MV Microchip Technology, PIC16F1937-E/MV Datasheet - Page 167

• Manufacturer Part Number: PIC16F1937-E/MV
• Description: 14KB Flash, 512B RAM, 256B EEPROM, LCD, 1.8-5.5V 40 UQFN 5x5x0.5mm TUBE
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 16Fr

Specifications of PIC16F1937-E/MV

• Processor Series: PIC16F
• Core: PIC
• Program Memory Type: Flash
• Program Memory Size: 14 KB
• Data Ram Size: 256 B
• Interface Type: MI2C, SPI, EUSART
• Number Of Timers: 5
• Operating Supply Voltage: 1.8 V to 5.5 V
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• Package / Case: UQFN-40
• Development Tools By Supplier: MPLAB IDE Software
• Minimum Operating Temperature: - 40 C
• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 32MHz
• Connectivity: I²C, LIN, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 36
• Eeprom Size: 256 x 8
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 14x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 125°C
• Lead Free Status / Rohs Status: Details

15.3
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 15-1:
 2008-2011 Microchip Technology Inc.
The value for T
Solving for T
Assumptions:
Therefore:
Note 1: The reference voltage (V
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
15-4.
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




+
T
1
1

C
 1
=
R
=
T

+
–
IC
C
15-4. The source
=
V
V
+
+

REF
+
+

A PP LIE D
CHOLD
recommended


7k
50°C and external impedance of 10k
Temperature - 25°C
T
R

COFF
) has no effect on the equation, since it cancels itself out.


=
SS
50°C- 25°C
+
+
HOLD
DD
V
10k
R
CHOLD
), refer


S
+
1
) is not discharged after each conversion.
 ln(1/511)

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.
–




PIC16(L)F1934/6/7
;[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
Equation 15-1
DS41364E-page 167
APPLIED
may be