Electrical characteristics
ST7L34, ST7L35, ST7L38, ST7L39
Doc ID 11928 Rev 7
13.2.1
Voltage characteristics
13.2.2
Current characteristics
Table 97.
Voltage characteristics
Symbol
Ratings
Maximum value
Unit
VDD - VSS
Supply voltage
7.0
V
VIN
Input voltage on any pin(1)(2)
1.
Directly connecting the RESET and I/O pins to VDD or VSS could damage the device if an unintentional
internal reset is generated or an unexpected change of the I/O configuration occurs (for example, due to a
corrupted program counter). To guarantee safe operation, this connection must be made through a pull-up
or pull-down resistor (typical: 4.7 k
Ω for RESET, 10 kΩ for I/Os). Unused I/O pins must be tied in the same
way to VDD or VSS according to their reset configuration.
2.
IINJ(PIN) must never be exceeded. This is implicitly insured if VIN maximum is respected. If VIN maximum
cannot be respected, the injection current must be limited externally to the IINJ(PIN) value. A positive
injection is induced by VIN >VDD while a negative injection is induced by VIN <VSS. For true open-drain
pads, there is no positive injection current and the corresponding VIN maximum must always be respected
VSS - 0.3 to VDD + 0.3
VESD(HBM)
Electrostatic discharge voltage (human body model)
VESD(MM)
Electrostatic discharge voltage (machine model)
Table 98.
Current characteristics
Symbol
Ratings
Maximum value
Unit
IVDD
Total current into VDD power lines (source)
(1)
1.
All power (VDD) and ground (VSS) lines must always be connected to the external supply.
150
mA
IVSS
Total current out of VSS ground lines (sink) 150
IIO
Output current sunk by any standard I/O and control pin
20
Output current sunk by any high sink I/O pin
40
Output current source by any I/Os and control pin
- 25
IINJ(PIN)
(2)(3)
2.
IINJ(PIN) must never be exceeded. This is implicitly insured if VIN maximum is respected. If VIN maximum
cannot be respected, the injection current must be limited externally to the IINJ(PIN) value. A positive
injection is induced by VIN >VDD while a negative injection is induced by VIN <VSS.
3.
Negative injection disturbs the analog performance of the device. In particular, it induces leakage currents
throughout the device including the analog inputs. To avoid undesirable effects on the analog functions,
care must be taken:
- Analog input pins must have a negative injection less than 0.8 mA (assuming that the impedance of the
analog voltage is lower than the specified limits)
- Pure digital pins must have a negative injection less than 1.6 mA. In addition, it is recommended to inject
the current as far as possible from the analog input pins.
Injected current on RESET pin
± 5
mA
Injected current on OSC1 and OSC2 pins
± 5
Injected current on any other pin(4)
4.
When several inputs are submitted to a current injection, the maximum
ΣIINJ(PIN) is the absolute sum of the
positive and negative injected currents (instantaneous values). These results are based on
characterization with
ΣIINJ(PIN) maximum current injection on four I/O port pins of the device.
± 5
Total injected current (sum of all I/O and control pins)
(4)± 20
mA