ELM622
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........................... -0.6V to (VDD + 0.6V)
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
1.0
2.4
Input low voltage
VSS
0.15 VDD
VDD
V
V
Input high voltage
0.85 VDD
Output low voltage
Output high voltage
Reset Output Pulse Width
Transmit Baud Rate
0.6
V
Current (sink) = 8.7mA
Current (source) = 5.4mA
see note 4
VDD - 0.7
V
90
100
110
msec
baud
9300
9600
9900
see notes 4 and 5
Notes:
1. This integrated circuit is produced with a Microchip Technology Inc.’s PIC12C5XX as the core embedded
microcontroller. For further device specifications, and possibly clarification of those given, please refer to the
appropriate Microchip documentation.
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 LED or drive currents.
4. Pulse timing is internally generated, and affected by both temperature and supply voltage. Times shown are
the widest variation that can normally be expected.
5. Data is sent at this rate with eight data bits, no parity bit, and one stop bit. Process and temperature
variatons could typically result in as much as 3% error in this rate, but most UARTs would be tolerant of this.
In high reliability applications, one might use the fact that the eighth data bit is always ‘0’ to calibrate a timing
loop to the ELM622’s speed. The receiver could then compensate for variations in the data rate.
3 of 5
ELM622DSA
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