PIC18F87K90-I/PTRSL Microchip Technology, PIC18F87K90-I/PTRSL Datasheet - Page 281

• Manufacturer Part Number: PIC18F87K90-I/PTRSL
• Description: MCU PIC 128K FLASH XLP 80TQFP
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 18Fr

Specifications of PIC18F87K90-I/PTRSL

• Core Size: 8-Bit
• Program Memory Size: 128KB (64K x 16)
• Core Processor: PIC
• Speed: 64MHz
• Connectivity: I²C, LIN, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 69
• Program Memory Type: FLASH
• Eeprom Size: 1K x 8
• Ram Size: 4K x 8
• Voltage - Supply (vcc/vdd): 1.8 V ~ 5.5 V
• Data Converters: A/D 24x12b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 80-TFQFP
• Controller Family/series: PIC18
• Eeprom Memory Size: 1024Byte
• Ram Memory Size: 4096Byte
• Cpu Speed: 16MIPS
• No. Of Timers: 11
• Processor Series: PIC18F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 4 KB
• Interface Type: I2C, SPI
• Maximum Clock Frequency: 64 MHz
• Number Of Timers: 11
• Operating Supply Voltage: 1.8 V to 5.5 V
• Maximum Operating Temperature: + 125 C
• Mounting Style: SMD/SMT
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734, 52712-325, EWPIC18
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 12 bit, 24 Channel
• A/d Bit Size: 12 bit
• A/d Channels Available: 24
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

There are two power modes designated as “Mode A”
and “Mode B”. Mode A is set by the bits, LRLAP<1:0>
and Mode B by LRLB<1:0>. The resistor ladder to use
for Modes A and B are selected by the bits,
LRLAP<1:0> and LRLBP<1:0>, respectively
Each ladder has a matching contrast control ladder,
tuned to the nominal resistance of the reference ladder.
This contrast control resistor can be controlled by
LCDREF<5:3> (LCDCST<2:0>). Disabling the internal
reference ladder results in all of the ladders being
disconnected, allowing external voltages to be
supplied.
To get additional current in High-Power mode, when
LCDRL<7:6> (LRLAP<1:0>) = 11, both the medium
and high-power resistor ladders are activated.
Whenever the LCD module is inactive (LCDA
(LCDPS<5>) = 0), the reference ladder will be turned
off.
FIGURE 20-5:
 2010 Microchip Technology Inc.
Segment Data
LRLAT<2:0>
Power Mode
lcd_32x_clk
cnt<4:0>
lcd_clk
'H00
LCD REFERENCE LADDER POWER MODE SWITCHING DIAGRAM
Power Mode A
LRLAT<2:0>
'H01
'H02
'H03
Single Segment Time
'H04
Preliminary
'H05
PIC18F87K90 FAMILY
20.3.2.1
As an LCD segment is electrically only a capacitor, cur-
rent is drawn only during the interval when the voltage
is switching. To minimize total device current, the LCD
reference ladder can be operated in a different power
mode for the transition portion of the duration. This is
controlled by the LCDRL register.
Mode A Power mode is active for a programmable time,
beginning at the time when the LCD segment waveform
is transitioning. The LCDRL<2:1> (LRLAT<2:0>) bits
select how long, or if the Mode A is active. Mode B
Power mode is active for the remaining time before the
segments or commons change again.
As shown in Figure 20-5, there are 32 counts in a single
segment time. Type-A can be chosen during the time
when the wave form is in transition. Type-B can be
used when the clock is stable or not in transition.
By using this feature of automatic power switching,
using Type-A/Type-B, the power consumption can be
optimized for a given contrast.
'H3
Power Mode B
'H06
'H07
Automatic Power Mode Switching
'H1E
'H1F
DS39957B-page 281
'H00
Mode A
'H01