PIC18LF2539T-I/SO Microchip Technology, PIC18LF2539T-I/SO Datasheet - Page 187

• Manufacturer Part Number: PIC18LF2539T-I/SO
• Description: IC MCU FLASH 12KX16 EE AD 28SOIC
• Manufacturer: Microchip Technology
• Series: PIC® 18Fr

Specifications of PIC18LF2539T-I/SO

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 40MHz
• Connectivity: I²C, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LVD, POR, PWM, WDT
• Number Of I /o: 21
• Program Memory Size: 24KB (12K x 16)
• Program Memory Type: FLASH
• Eeprom Size: 256 x 8
• Ram Size: 1408 x 8
• Voltage - Supply (vcc/vdd): 2 V ~ 5.5 V
• Data Converters: A/D 5x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-SOIC (7.5mm Width)
• Processor Series: PIC18LF
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 1408 B
• Interface Type: I2C, SPI, AUSART
• Maximum Clock Frequency: 40 MHz
• Number Of Programmable I/os: 21
• Number Of Timers: 16 bit
• Operating Supply Voltage: 2 V to 5.5 V
• Maximum Operating Temperature: + 85 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734, 52712-325, EWPIC18
• Development Tools By Supplier: DV164005, DV164136
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 5 bit
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

To
Equation 18-1 may be used. This equation assumes
that 1/2 LSb error is used (1024 steps for the A/D). The
1/2 LSb error is the maximum error allowed for the A/D
to meet its specified resolution.
EQUATION 18-1:
EQUATION 18-2:
Example 18-1 shows the calculation of the minimum
required acquisition time, T
based
assumptions:
• C
• Rs
• Conversion Error ≤
• V
• Temperature
• V
EXAMPLE 18-1:
 2002 Microchip Technology Inc.
T
V
or
T
T
Temperature coefficient is only required for temperatures > 25°C.
T
T
T
ACQ
C
ACQ
ACQ
C
ACQ
HOLD
DD
HOLD
HOLD
calculate
=
=
=
=
=
=
=
=
on
T
2 µs + T
-C
-120 pF (1 kΩ + 7 kΩ + 2.5 kΩ) ln(0.0004883)
-120 pF (10.5 kΩ) ln(0.0004883)
-1.26 µs (-7.6246)
9.61 µs
2 µs + 9.61 µs + [(50°C – 25°C)(0.05 µs/°C)]
11.61 µs + 1.25 µs
12.86 µs
AMP
Amplifier Settling Time + Holding Capacitor Charging Time + Temperature Coefficient
(V
-(120 pF)(1 kΩ + R
T
HOLD
AMP
the
REF
the
+ T
+ T
C
– (V
(R
C
following
+ [(Temp – 25°C)(0.05 µs/°C)]
=
=
=
=
=
IC
ACQUISITION TIME
C
A/D MINIMUM CHARGING TIME
+ T
CALCULATING THE MINIMUM REQUIRED ACQUISITION TIME
minimum
REF
+ T
+ R
COFF
120 pF
2.5 kΩ
1/2 LSb
5V → Rss = 7 kΩ
50°C (system max.)
0V @ time = 0
/2048)) • (1 – e
COFF
SS
ACQ
+ R
SS
. This calculation is
application
S
+ R
) ln(1/2048)
acquisition
S
) ln(1/2048)
(-Tc/C
HOLD
system
time,
(R
Preliminary
IC
+ R
SS
+ R
S
))
)
PIC18FXX39
DS30485A-page 185