TTL Input/Output
Specification of the TTL GPIO input/output ports
Simplified schematic
The receiver is LVTTL and 5 V TTL compliant. The driver is a 3.3 V TTL driver
DC characteristics
Parameter | Conditions | Min. | Typ. | Max. | Units |
---|---|---|---|---|---|
Common mode input voltage | 0 | 5 | V | ||
Low-level output current | 64 | mA | |||
Low-level output voltage | @ 16 mA | 0.64 | V | ||
@ 32 mA | 0.98 | V | |||
@ 64 mA | 1.51 | V | |||
High-level output current | -32 | mA | |||
High-level output voltage | @-8 mA | 2.28 | V | ||
@-32 mA | 1.52 | V | |||
ESD protection | Human Body Model (HBM) | 2 | kV |
Note: The I/O port includes a latch-up protection.
AC characteritics
Parameter | Min. | Typ. | Max. | Units |
---|---|---|---|---|
Pulse width | 100 | ns | ||
Pulse rate | 0 | 5 | MHz | |
10%-90% rise/fall time | 1 | µs |
Logical Map
The state of the port is reported as follows:
Input voltage | Logical State |
---|---|
VIN > 2.0 V | HIGH |
VIN < 0.8 V | LOW |
Unconnected input port | Undetermined |
Compatible drivers and receivers
The following drivers are compatible:
- Totem-pole LVTTL, TTL, 5 V CMOS drivers
The following receivers are compatible:
- LVTTL, TTL, 3-Volt CMOS receivers