PIC16F1937-I/P Microchip Technology, PIC16F1937-I/P Datasheet - Page 252

• Manufacturer Part Number: PIC16F1937-I/P
• Description: IC PIC MCU FLASH 512KX14 40-PDIP
• Manufacturer: Microchip Technology
• Series: PIC® XLP™ 16Fr

Specifications of PIC16F1937-I/P

• Program Memory Type: FLASH
• Program Memory Size: 14KB (8K x 14)
• Package / Case: 40-DIP (0.600", 15.24mm)
• 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 ~ 85°C
• Processor Series: PIC16F
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 512 B
• Interface Type: EUSART/MI2C/SPI
• Maximum Clock Frequency: 32 MHz
• Number Of Programmable I/os: 36
• Number Of Timers: 5
• Maximum Operating Temperature: + 85 C
• Mounting Style: Through Hole
• 3rd Party Development Tools: 52715-96, 52716-328, 52717-734
• Development Tools By Supplier: PG164130, DV164035, DV244005, DV164005
• Minimum Operating Temperature: - 40 C
• On-chip Adc: 14-ch x 10-bit
• A/d Bit Size: 10 bit
• A/d Channels Available: 14
• Height: 4.95 mm
• Length: 53.21 mm
• Supply Voltage (max): 5.5 V
• Supply Voltage (min): 1.8 V
• Width: 14.73 mm
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

PIC16F193X/LF193X
21.4
The internal reference ladder can be used to divide the
LCD bias voltage two or three equally spaced voltages
that will be supplied to the LCD segment pins. To create
this, the reference ladder consists of three matched
resistors. Refer to Figure 21-3.
21.4.1
When in 1/2 Bias mode (BIASMD = 1), then the middle
resistor of the ladder is shorted out so that only two
voltages are generated. The current consumption of the
ladder is higher in this mode, with the one resistor
removed.
TABLE 21-3:
DS41364A-page 250
Low
Medium
High
Power
Mode
LCD Bias Internal Reference
Ladder
BIAS MODE INTERACTION
Nominal Resistance of
LCD INTERNAL LADDER
POWER MODES (1/3 BIAS)
Entire Ladder
300 kohm
30 kohm
3 Mohm
Nominal
100 µA
10 µA
1 µA
I
DD
Preliminary
21.4.2
The internal reference ladder may be operated in one of
three power modes. This allows the user to trade off LCD
contrast for power in the specific application. The larger
the LCD glass, the more capacitance is present on a
physical LCD segment, requiring more current to
maintain the same contrast level.
Three different power modes are available, LP, MP and
HP. The internal reference ladder can also be turned off
for applications that wish to provide an external ladder
or to minimize power consumption. Disabling the
internal reference ladder results in all of the ladders
being disconnected, allowing external voltages to be
supplied.
Whenever the LCD module is inactive (LCDA = 0), the
internal reference ladder will be turned off.
POWER MODES
© 2008 Microchip Technology Inc.