ROBUSTNESS FEATURES
The PALCE22V10X-X/5 devices have some unique features that make them extremely robust,
especially when operating in high-speed design environments. Pull-up resistors on inputs and I/O
pins cause unconnected pins to default to a known state. Input clamping circuitry limits negative
overshoot, eliminating the possibility of false clocking caused by subsequent ringing. A special
noise filter makes the programming circuitry completely insensitive to any positive overshoot that
has a pulse width of less than about 100 ns for the /5 version.
INPUT/OUTPUT EQUIVALENT SCHEMATICS FOR /5 VERSION DEVICES
V
V
CC
CC
> 50 kΩ
Programming
Pins only
Positive
Overshoot
Filter
Programming
Voltage
Detection
Programming
Circuitry
ESD
Protection
and
Clamping
Typical Input
V
V
CC
CC
> 50 kΩ
Provides ESD
Protection and
Clamping
Preload
Circuitry
Feedback
Input
16564-16
Typical Output
PALCE22V10 and PALCE22V10Z Families
29
LATTICE [ LATTICE SEMICONDUCTOR ]
