PIC14000-04/SS Microchip Technology, PIC14000-04/SS Datasheet - Page 61

• Manufacturer Part Number: PIC14000-04/SS
• Description: IC MCU OTP 4KX14 A/D 28SSOP
• Manufacturer: Microchip Technology
• Series: PIC® 14r

Specifications of PIC14000-04/SS

• Core Processor: PIC
• Core Size: 8-Bit
• Speed: 4MHz
• Connectivity: I²C
• Peripherals: POR, Temp Sensor, WDT
• Number Of I /o: 20
• Program Memory Size: 7KB (4K x 14)
• Program Memory Type: OTP
• Ram Size: 192 x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 6 V
• Data Converters: Slope A/D
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 28-SSOP
• Processor Series: PIC14000
• Core: PIC
• Data Bus Width: 8 bit
• Data Ram Size: 192 B
• Interface Type: SPI, UART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 22
• Number Of Timers: 1
• Operating Supply Voltage: 2.7 V to 6 V
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Development Tools By Supplier: ICE2000
• Minimum Operating Temperature: 0 C
• On-chip Adc: 14 bit
• For Use With: 309-1025 - ADAPTER 28-SSOP TO 28-DIPXLT28SS-1 - SOCKET TRANSITION ICE 28SSOP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Lead Free Status / Rohs Status: Details

8.6
Four configuration bits (ADCON1<7:4>) are used to
control a programmable current source for generating
the ramp voltage to the A/D comparator. It allows com-
pensation for full-scale input voltage, clock frequency
and CDAC capacitor tolerance variations. The current
values range from 0 to 33.75 A (nominal) in 2.25 A
increments. The intermediate values of the current
source are as follows:
TABLE 8-2:
1996 Microchip Technology Inc.
0
0
0
0
0
0
0
0
1
1
1
1
1
1
1
1
ADCON1<7:4>
Programmable Current Source
0
1
0
0
0
1
1
1
0
0
0
0
1
1
1
1
0
0
1
1
0
0
1
1
0
0
1
1
0
0
1
1
PROGRAMMABLE CURRENT
SOURCE SELECTION
0
1
0
1
0
1
0
1
0
1
0
1
0
1
0
1
OFF - all current
sources disabled
2.25 A
4.5 A
6.75 A
9 A
11.25 A
13.5 A
15.75 A
18 A
20.25 A
22.5 A
24.75 A
27 A
29.25 A
31.5 A
33.75 A
Current Source
Output
Preliminary
The programmable current source output is tied to the
CDAC pin and is used to charge an external capacitor
to generate the ramp voltage for the A/D comparator.
(Refer to Figure 8-1.) This capacitor should have a low
voltage-coefficient as found in teflon, polypropylene, or
polystyrene capacitors, for optimum results. The
capacitor must be discharged at the beginning of each
conversion cycle by asserting ADRST (ADCON0<1>)
for at least 200
Asserting ADRST disables the current sources inter-
nally. Current flow begins when ADRST is cleared.
s to allow a complete discharge.
PIC14000
DS40122B-page 61