Specifications

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the dsPIC33FJ256GP710A. The cost of the microcontroller itself is a very small
percentage of our overall costs, but we kept in mind that should this system be
mass produced, even the cheapest of components amounts to a significant
amount of money and therefore cost should be considered for ever component.
During development, we must stay within the specified Absolute Maximum
Electrical values. We must avoid subjecting the chip to extreme temperatures,
input voltages it is not designed to handle, and drawing or sending too much
voltage or current from the I/O pins. The parameters that must be taken into
consideration are listed below.
 Ambient temperature under bias: -40˚C to +125˚C
 Storage temperature: -65˚C to +150˚C
 Voltage on V
DD
with respect to V
SS
: -0.3V to +4.0V
 Voltage on any pin that is not 5V tolerant with respect to
V
SS
: -0.3V (V
DD
+ 0.3V)
 Voltage on any 5V tolerant pin with respect to V
SS
when V
DD
≥ 3.0V:
-0.3V to +5.6V
 Voltage on any 5V tolerant pin with respect to V
SS
when V
DD
< 3.0V:
-0.3V to (V
DD
+ 0.3V)
 Voltage on V
CAP
/V
DDCORE
with respect to V
SS
: 2.25V to 2.75V
 Maximum current out of V
SS
pin: 300mA
 Maximum current into V
DD
pin: 250mA
 Maximum output current sunk by any I/O pin: 4mA
 Maximum output current sourced by any I/O pin: 4mA
 Maximum current sunk by all ports: 200mA
 Maximum current sourced by all ports: 200mA
Note: Exposure to maximum rating conditions for extended periods of time may
affect device reliability.
2.2.2 Pins
The dsPIC33FJ256GP710A main microcontroller has a total of 100 pins on the
chip. Some pins are required to be connected at all times, some will be
connected depending on our final main control unit design, and some will be left
unconnected or “floating.” Pins that are required to be connected at all times are
shown in Table 3 below. The Pin Name, Pin Type, and Description are included
in the table.