DSPIC30F2020-30I/MM Microchip Technology, DSPIC30F2020-30I/MM Datasheet - Page 21

• Manufacturer Part Number: DSPIC30F2020-30I/MM
• Description: IC DSPIC MCU/DSP 12K 28QFN
• Manufacturer: Microchip Technology
• Series: dsPIC™ 30Fr

Specifications of DSPIC30F2020-30I/MM

• Core Processor: dsPIC
• Core Size: 16-Bit
• Speed: 30 MIPs
• Connectivity: I²C, IrDA, LIN, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 21
• Program Memory Size: 12KB (4K x 24)
• Program Memory Type: FLASH
• Ram Size: 512 x 8
• Voltage - Supply (vcc/vdd): 3 V ~ 5.5 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: -40°C ~ 85°C
• Package / Case: 28-QFN
• Core Frequency: 15MHz
• Core Supply Voltage: 3.3V
• Embedded Interface Type: I2C, SPI, UART
• No. Of I/o's: 21
• Flash Memory Size: 12KB
• Supply Voltage Range: 3V To 3.6V
• Package: 28QFN-S EP
• Device Core: dsPIC
• Family Name: dsPIC30
• Maximum Speed: 30 MHz
• Operating Supply Voltage: 3.3|5 V
• Data Bus Width: 16 Bit
• Number Of Programmable I/os: 21
• Interface Type: I2C/SPI/UART
• On-chip Adc: 8-chx10-bit
• Number Of Timers: 3
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• For Use With: DM300023 - KIT DEMO DSPICDEM SMPS BUCKAC164322 - MODULE SOCKET MPLAB PM3 28/44QFNDV164005 - KIT ICD2 SIMPLE SUIT W/USB CABLE
• Eeprom Size: -
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant

48. Module: EXTREF Pin
TABLE 6:
FIGURE 2:
© 2010 Microchip Technology Inc.
Digital Input
Comparator Input
Comparator Reference
Analog Input
External Timer Input
Input Change Notification
The EXTREF pin is susceptible to voltage spikes
below V
into the pin. A voltage below V
outside the operating specification of the device;
however, the device is designed to tolerate small
voltage and current transients without experiencing
detrimental effects. The EXTREF pin is more
susceptible to negative current spikes than the
other pins on the dsPIC30F1010/202X A3 devices.
The addition of the 100 ohms resistor effectively
makes the EXTREF pin as robust as the other pins
on the device with respect to tolerating voltage and
current transients. In most of the configurations
shown in Table 6, the 100 ohms resistor will have
little effect on the operation of the pin. An
exception to this is when the pin is configured as
the comparator reference, EXTREF. Adding a
resistor in series with the reference voltage will
cause a slight offset in the gain of the comparator
DAC. This gain offset is related to the voltage drop
across the 100 ohms resistor.
The voltage seen at the EXTREF pin is given by
Equation 4.
Pin Configuration
SS
, which induces negative current flow
EXTREF PIN CONFIGURATIONS SUSCEPTIBLE TO NEGATIVE CURRENT
TRANSIENTS
dsPIC30F2020
ADDITION OF 100 OHMS RESISTOR ON EXTREF PIN
EXTREF
SS
dsPIC30F1010
on any I/O pin is
EXTREF
T1CK
CN0
RE6
N/A
N/A
100Ω
R1
EQUATION 4:
dsPIC30F1010/202X
dsPIC30F2020
V
EXTREF
Work around
If the EXTREF pin is used in any of the
configurations
recommended that a 100 ohms 1/8W resistor be
added in series with the EXTREF pin (see
Figure 2).
Where:
• V
• V
• R is the resistor in series on the pin (100 ohms
Affected Silicon Revisions
EXTREF
A1
voltage.
recommended).
X
T1CK
CN0
RE6
EXTREF
REF
N/A
N/A
=
To Application Circuit
is the supplied comparator reference
A2
V
is the voltage seen at the EXTREF pin.
REF
A3
- R
EXTREF VOLTAGE
shown
·
(No of Comparators)
40,000 ohm + R
in
dsPIC30F2023
EXTREF
CMP4D
DS80445D-page 21
Table 6,
RB9
AN9
N/A
N/A
·
V
REF
it
is