PIC18F86K90-I/PT Microchip Technology, PIC18F86K90-I/PT Datasheet - Page 279

• Manufacturer Part Number: PIC18F86K90-I/PT
• Description: 64kB Flash, 4kB RAM, 1kB EE, 16MIPS, NanoWatt XLP, LCD, 5V 80 TQFP 12x12x1mm TRA
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 18Fr

Specifications of PIC18F86K90-I/PT

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 64MHz
• Connectivity: I²C, LIN, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, LCD, POR, PWM, WDT
• Number Of I /o: 69
• Program Memory Size: 64KB (32K x 16)
• 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-TQFP
• Lead Free Status / Rohs Status: Lead free / RoHS Compliant

20.3
The LCD module can be configured in one of three bias
types:
• Static bias (two voltage levels: V
• 1/2 bias (three voltage levels: V
• 1/3 bias (four voltage levels: V
LCD bias voltages can be generated with an internal or
external resistor ladder. The internal resistor ladder
eliminates the external solution’s use of up to three
pins.
FIGURE 20-3:
 2010 Microchip Technology Inc.
V
2/3 V
* These values are provided for design guidance only and should be optimized for the application by the designer.
AV
AV
AV
DD
DD
DD
DD
)
DD
*
*
*
LCD Bias Types
and V
LCD Bias 3
DD
10 k*
10 k*
)
LCD BIAS EXTERNAL RESISTOR LADDER CONNECTION DIAGRAM
LCD Bias 2
SS
10 k*
SS
SS
, 1/3 V
, 1/2 V
and V
DD
DD
DD
,
LCD Bias 1
and
)
10 k*
10 k*
Preliminary
VLCD3
VLCD2
VLCD1
VLCD0
PIC18F87K90 FAMILY
If the internal reference ladder is used to generate bias
voltages, it also can provide software contrast control
(using LCDCST<2:0>). An external resistor ladder can
not do this.
20.3.1
The external resistor ladder should be connected to the
VLCD1 pin (Bias 1), VLCD2 pin (Bias 2), VLCD3 pin
(Bias 3) and V
highest voltage to the LCD glass and can be connected
to V
Figure 20-3 shows the proper way to connect the
resistor ladder to the Bias pins.
Connections for External R-ladder
To
LCD
Driver
DD
AV
AV
or a lower voltage.
SS
SS
EXTERNAL RESISTOR BIASING
VLCD0
VLCD1
VLCD2
VLCD3
Static Bias
1/2 Bias
1/3 Bias
SS
. The VLCD3 pin is used to set the
Static
AV
AV
Bias
—
—
SS
DD
1/2 AV
1/2 AV
1/2 Bias 1/3 Bias
AV
AV
DS39957B-page 279
SS
DD
DD
DD
1/3 AV
2/3 AV
AV
AV
SS
DD
DD
DD