PIC18F442-I/PT Microchip Technology Inc., PIC18F442-I/PT Datasheet - Page 28
![no-image](/images/manufacturer_photos/0/4/440/microchip_technology_inc__sml.jpg)
PIC18F442-I/PT
Manufacturer Part Number
PIC18F442-I/PT
Description
Microcontroller; 16 KB Flash; 768 RAM; 256 EEPROM; 36 I/O; 40-Pin-TQFP
Manufacturer
Microchip Technology Inc.
Datasheet
1.PIC18F442-IPT.pdf
(332 pages)
Specifications of PIC18F442-I/PT
A/d Inputs
8-Channel, 10-Bit
Comparators
2
Cpu Speed
10 MIPS
Eeprom Memory
256 Bytes
Input Output
36
Interface
I2C/SPI/USART
Memory Type
Flash
Number Of Bits
8
Package Type
44-pin TQFP
Programmable Memory
16K Bytes
Ram Size
768 Bytes
Speed
40 MHz
Timers
1-8-bit, 3-16-bit
Voltage, Range
2-5.5 V
Lead Free Status / Rohs Status
RoHS Compliant part
Available stocks
Company
Part Number
Manufacturer
Quantity
Price
Company:
Part Number:
PIC18F442-I/PT
Manufacturer:
Microchip Technology
Quantity:
10 000
- Current page: 28 of 332
- Download datasheet (6Mb)
PIC18FXX2
3.1
A Power-on Reset pulse is generated on-chip when
V
cuitry, just tie the MCLR pin directly (or through a resis-
tor) to V
usually needed to create a Power-on Reset delay. A
minimum
(parameter D004). For a slow rise time, see Figure 3-2.
When the device starts normal operation (i.e., exits the
RESET condition), device operating parameters (volt-
age, frequency, temperature, etc.) must be met to
ensure operation. If these conditions are not met, the
device must be held in RESET until the operating
conditions are met.
FIGURE 3-2:
3.2
The Power-up Timer provides a fixed nominal time-out
(parameter 33) only on power-up from the POR. The
Power-up Timer operates on an internal RC oscillator.
The chip is kept in RESET as long as the PWRT is
active. The PWRT’s time delay allows V
acceptable level. A configuration bit is provided to
enable/disable the PWRT.
The power-up time delay will vary from chip-to-chip due
to V
parameter D033 for details.
DS39564C-page 26
DD
Note 1: External Power-on Reset circuit is required
DD
rise is detected. To take advantage of the POR cir-
, temperature and process variation. See DC
DD
Power-On Reset (POR)
Power-up Timer (PWRT)
2: R < 40 k is recommended to make sure that
3: R1 = 100
. This will eliminate external RC components
D
rise
only if the V
The diode D helps discharge the capacitor
quickly when V
the voltage drop across R does not violate
the device’s electrical specification.
ing into MCLR from external capacitor C, in
the event of MCLR/V
Electrostatic Discharge (ESD) or Electrical
Overstress (EOS).
V
DD
R
rate
C
EXTERNAL POWER-ON
RESET CIRCUIT (FOR
SLOW V
to 1 k will limit any current flow-
DD
DD
for
R1
power-up slope is too slow.
powers down.
PP
DD
V
PIC18FXXX
pin breakdown due to
DD
MCLR
POWER-UP)
DD
is
to rise to an
specified
3.3
The Oscillator Start-up Timer (OST) provides a 1024
oscillator cycle (from OSC1 input) delay after the
PWRT delay is over (parameter 32). This ensures that
the crystal oscillator or resonator has started and
stabilized.
The OST time-out is invoked only for XT, LP and HS
modes and only on Power-on Reset or wake-up from
SLEEP.
3.4
With the PLL enabled, the time-out sequence following
a Power-on Reset is different from other Oscillator
modes. A portion of the Power-up Timer is used to pro-
vide a fixed time-out that is sufficient for the PLL to lock
to the main oscillator frequency. This PLL lock time-out
(T
start-up time-out (OST).
3.5
A configuration bit, BOREN, can disable (if clear/
programmed), or enable (if set) the Brown-out Reset
circuitry. If V
than parameter 35, the brown-out situation will reset
the chip. A RESET may not occur if V
parameter D005 for less than parameter 35. The chip
will remain in Brown-out Reset until V
BV
invoked after V
the chip in RESET for an additional time delay
(parameter 33). If V
Power-up Timer is running, the chip will go back into a
Brown-out Reset and the Power-up Timer will be initial-
ized. Once V
will execute the additional time delay.
3.6
On power-up, the time-out sequence is as follows:
First, PWRT time-out is invoked after the POR time
delay has expired. Then, OST is activated. The total
time-out will vary based on oscillator configuration and
the status of the PWRT. For example, in RC mode with
the PWRT disabled, there will be no time-out at all.
Figure 3-3, Figure 3-4, Figure 3-5, Figure 3-6 and
Figure 3-7 depict time-out sequences on power-up.
Since the time-outs occur from the POR pulse, if MCLR
is kept low long enough, the time-outs will expire.
Bringing MCLR high will begin execution immediately
(Figure 3-5). This is useful for testing purposes or to
synchronize more than one PIC18FXXX device operat-
ing in parallel.
Table 3-2 shows the RESET conditions for some
Special Function Registers, while Table 3-3 shows the
RESET conditions for all the registers.
PLL
DD
) is typically 2 ms and follows the oscillator
. If the Power-up Timer is enabled, it will be
Oscillator Start-up Timer (OST)
PLL Lock Time-out
Brown-out Reset (BOR)
Time-out Sequence
DD
DD
DD
falls below parameter D005 for greater
rises above BV
rises above BV
DD
© 2006 Microchip Technology Inc.
drops below BV
DD
, the Power-up Timer
DD
; it then will keep
DD
DD
DD
rises above
falls below
while the
Related parts for PIC18F442-I/PT
Image
Part Number
Description
Manufacturer
Datasheet
Request
R
![PIC18F-LF1XK50](/images/no-image3.png)
Part Number:
Description:
20-Pin USB Flash Microcontrollers
Manufacturer:
MICROCHIP [Microchip Technology]
Datasheet:
![PIC18F6393T-I/PT](/photos/6/81/68123/c04-066_pf_tmb.jpg)
Part Number:
Description:
PIC18F With 128-segment LCD Driver And 12-bit ADC, 8KB Flash, 768B RAM, CCP, MSS
Manufacturer:
Microchip Technology
Datasheet:
![PIC18F6493T-I/PT](/photos/6/81/68123/c04-066_pf_tmb.jpg)
Part Number:
Description:
PIC18F With 128-segment LCD Driver And 12-bit ADC, 16KB Flash, 768B RAM, CCP, MS
Manufacturer:
Microchip Technology
Datasheet:
![PIC18F8393T-I/PT](/images/manufacturer_photos/0/4/439/microchip_technology_tmb.jpg)
Part Number:
Description:
PIC18F With 192-segment LCD Driver And 12-bit ADC, 8KB Flash, 768B RAM, CCP, MSS
Manufacturer:
Microchip Technology
Datasheet:
![PIC18F8493T-I/PT](/images/manufacturer_photos/0/4/439/microchip_technology_tmb.jpg)
Part Number:
Description:
PIC18F With 192-segment LCD Driver And 12-bit ADC, 16KB Flash, 768B RAM, CCP, MS
Manufacturer:
Microchip Technology
Datasheet:
![PIC18F6585-I/L](/photos/16/12/161282/68-plcc-large-300dpi-lyrd_tmb.jpg)
Part Number:
Description:
Microcontrollers (MCU) 48KB 3328 RAM 52 I/O
Manufacturer:
Microchip Technology
Datasheet:
![PIC18F6680-I/L](/photos/16/12/161282/68-plcc-large-300dpi-lyrd_tmb.jpg)
Part Number:
Description:
Microcontrollers (MCU) 64KB 3328 RAM 52 I/O
Manufacturer:
Microchip Technology
Datasheet:
![PIC18F65K90T-I/MR](/photos/16/3/160368/qfn64_tmb.jpg)
Part Number:
Description:
32kB Flash, 2kB RAM, 1kB EE, NanoWatt XLP, LCD 64 QFN 9x9x0.9mm T/R
Manufacturer:
Microchip Technology
Datasheet:
![PIC18F65K90T-I/PT](/photos/16/3/160367/tqfp-64_tmb.jpg)
Part Number:
Description:
32kB Flash, 2kB RAM, 1kB EE, NanoWatt XLP, LCD 64 TQFP 10x10x1mm T/R
Manufacturer:
Microchip Technology
Datasheet:
![PIC18F87K90T-I/PT](/photos/40/31/403173/tqfp-80_tmb.jpg)
Part Number:
Description:
128kB Flash, 4kB RAM, 1kB EE, 16MIPS, NanoWatt XLP, LCD, 5V 80 TQFP 12x12x1mm T/
Manufacturer:
Microchip Technology
Datasheet:
![PIC18F65K90-I/MR](/photos/16/3/160368/qfn64_tmb.jpg)
Part Number:
Description:
32kB Flash, 2kB RAM, 1kB EE, NanoWatt XLP, LCD 64 QFN 9x9x0.9mm TUBE
Manufacturer:
Microchip Technology
Datasheet:
![PIC18F65K90-I/PT](/photos/16/3/160367/tqfp-64_tmb.jpg)
Part Number:
Description:
32kB Flash, 2kB RAM, 1kB EE, NanoWatt XLP, LCD 64 TQFP 10x10x1mm TRAY
Manufacturer:
Microchip Technology
![PIC18F87K90-I/PT](/photos/40/31/403173/tqfp-80_tmb.jpg)
Part Number:
Description:
128kB Flash, 4kB RAM, 1kB EE, 16MIPS, NanoWatt XLP, LCD, 5V 80 TQFP 12x12x1mm TR
Manufacturer:
Microchip Technology