ELM327
Absolute Maximum Ratings
Storage Temperature....................... -65°C to +150°C
Note:
Stresses beyond those listed here will likely damage
the device. These values are given as a design
guideline only. The ability to operate to these levels
is neither inferred nor recommended.
Ambient Temperature with
Power Applied....................................-40°C to +85°C
Voltage on VDD with respect to VSS............0 to +7.5V
Voltage on any other pin with
respect to VSS........................... -0.3V to (VDD + 0.3V)
Electrical Characteristics
All values are for operation at 25°C and a 5V supply, unless otherwise noted. For further information, refer to note 1 below.
Characteristic
Minimum Typical
Maximum Units
Conditions
Supply voltage, VDD
VDD rate of rise
4.5
5.0
5.5
V
see note 2
see note 3
0.05
V/ms
mA
Average supply current, IDD
9
all except Schmitt inputs
see note 4
Input threshold voltage
1.0
1.0
1.3
4.0
V
Schmitt trigger
input thresholds
rising
falling
2.9
1.5
0.3
4.6
4.2
V
V
V
V
V
Output low voltage
current (sink) = 10 mA
Output high voltage
Brown-out reset voltage
current (source) = 10 mA
4.07
4.59
see note 5
A/D conversion time
7
msec
Notes:
1. This integrated circuit is produced with one of Microchip Technology Inc.’s PIC18F2x8x family of devices as
the core embedded microcontroller. For further device specifications, and possibly clarification of those
given, please refer to the appropriate Microchip documentation (available at http://www.microchip.com/).
2. This spec must be met in order to ensure that a correct power on reset occurs. It is quite easily achieved
using most common types of supplies, but may be violated if one uses a slowly varying supply voltage, as
may be obtained through direct connection to solar cells or some charge pump circuits.
3. Device only. Does not include any load currents.
4. Pins 1, 11, 12, 13, 15 and 18 (only) have internal Schmitt trigger waveshaping circuitry. All other inputs use
standard CMOS circuitry.
5. The typical width of the Busy output pulse while the ELM327 interprets the command, measures the voltage,
scales it and then transmits the result of a mid-range measurement, with the RS232 rate at 38400 baud.
ELM327DSC
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