PIC16F737-I/SP Microchip Technology Inc., PIC16F737-I/SP Datasheet - Page 169

• Manufacturer Part Number: PIC16F737-I/SP
• Description: 28 PIN, 7 KB FLASH, 368 RAM, 25 I/O
• Manufacturer: Microchip Technology Inc.

Specifications of PIC16F737-I/SP

• A/d Inputs: 5-Channel, 8-Bit
• Cpu Speed: 5 MIPS
• Eeprom Memory: 0 Bytes
• Input Output: 25
• Interface: I2C/SPI/USART
• Memory Type: Flash
• Number Of Bits: 8
• Package Type: 28-pin SPDIP
• Programmable Memory: 7K Bytes
• Ram Size: 192 Bytes
• Speed: 20 MHz
• Timers: 2-8-bit, 1-16-bit
• Voltage, Range: 2-5.5 V
• Lead Free Status / Rohs Status: RoHS Compliant part Electrostatic Device

14.0
The comparator voltage reference generator is a 16-tap
resistor ladder network that provides a fixed voltage
reference when the comparators are in mode ‘110’. A
programmable register controls the function of the
reference generator. Register 14-1 lists the bit functions
of the CVRCON register.
As shown in Figure 14-1, the resistor ladder is seg-
mented to provide two ranges of CV
a power-down function to conserve power when the
reference is not being used. The comparator reference
REGISTER 14-1:
 2004 Microchip Technology Inc.
COMPARATOR VOLTAGE
REFERENCE MODULE
bit 7
bit 6
bit 5
bit 4
bit 3-0
CVRCON: COMPARATOR VOLTAGE REFERENCE CONTROL REGISTER
(ADDRESS 9Dh)
bit 7
CVREN: Comparator Voltage Reference Enable bit
1 = CV
0 = CV
CVROE: Comparator V
1 = CV
0 = CV
CVRR: Comparator V
1 = 0 to 0.625 CV
0 = 0.25 CV
Unimplemented: Read as ‘0’
CVR3:CVR0: Comparator V
When CVRR = 1:
CV
When CVRR = 0:
CV
Legend:
R = Readable bit
-n = Value at POR
CVREN
R/W-0
REF
REF
REF
REF
REF
REF
= (CVR<3:0>/24) (CV
= 1/4 (CV
circuit powered on
circuit powered down
voltage level is output on RA2/AN2/V
voltage level is disconnected from RA2/AN2/V
REF
RSRC
CVROE
R/W-0
values and has
RSRC
to 0.72 CV
RSRC
REF
, with CV
REF
) + (CVR3:CVR0/32) (CV
R/W-0
CVRR
Range Selection bit
Output Enable bit
REF
W = Writable bit
‘1’ = Bit is set
RSRC
RSRC
RSRC
Value Selection bits 0
, with CV
)
/24 step size
U-0
—
supply voltage (also referred to as CV
directly from V
voltage at the top of the ladder is CV
where V
switch transistor. This reference will only be as
accurate as the values of CV
The output of the reference generator may be
connected to the RA2/AN2/V
be used as a simple D/A function by the user if a very
high-impedance load is used. The primary purpose of
this function is to provide a test path for testing the
reference generator function.
RSRC
/32 step size
REF
SAT
R/W-0
CVR3
U = Unimplemented bit, read as ‘0’
‘0’ = Bit is cleared
RSRC
-/CV
is the saturation voltage of the power
DD
)
REF
CVR3:CVR0
. It should be noted, however, that the
REF
pin
-/CV
R/W-0
CVR2
REF
PIC16F7X7
RSRC
REF
pin
15
x = Bit is unknown
-/CV
R/W-0
CVR1
and V
DS30498C-page 167
REF
RSRC
SAT
RSRC
pin. This can
.
R/W-0
CVR0
) comes
– V
bit 0
SAT
,