Owner manual

13
ATF1508AS(L)
0784O–PLD–09/02
Power-down
Mode
The ATF1508AS includes two pins for optional pin-controlled power-down feature. When this
mode is enabled, the PD pin acts as the power-down pin. When the PD1 and PD2 pin is high,
the device supply current is reduced to less than 10 mA. During power-down, all output data
and internal logic states are latched and held. Therefore, all registered and combinatorial out-
put data remain valid. Any outputs that were in a high-Z state at the onset will remain at high-
Z. During power-down, all input signals except the power-down pin are blocked. Input and I/O
hold latches remain active to ensure that pins do not float to indeterminate levels, further
reducing system power. The power-down pin feature is enabled in the logic design file.
Designs using either power-down pin may not use the PD pin logic array input. However, bur-
ied logic resources in this macrocell may still be used.
Notes: 1. For slow slew outputs, add t
SSO
.
2. Pin or product term.
Power-down AC Characteristics
(1)(2)
Symbol Parameter
-7 -10 -15 -20 -25
UnitsMin Max Min Max Min Max Min Max Min Max
t
IVDH
Valid I, I/O before PD High 7 10 15 20 25 ns
t
GVDH
Valid OE
(2)
before PD High 7 10 15 20 25 ns
t
CVDH
Valid Clock
(2)
before PD High 7 10 15 20 25 ns
t
DHIX
I, I/O Don’t Care after PD High 12 15 25 30 35 ns
t
DHGX
OE
(2)
Don’t Care after PD High 12 15 25 30 35 ns
t
DHCX
Clock
(2)
Don’t Care after PD High 12 15 25 30 35 ns
t
DLIV
PD Low to Valid I, I/O 1 1 1 1 1 µs
t
DLGV
PD Low to Valid OE (Pin or Term) 1 1 1 1 1 µs
t
DLCV
PD Low to Valid Clock (Pin or Term) 1 1 1 1 1 µs
t
DLOV
PD Low to Valid Output 1 1 1 1 1 µs
Absolute Maximum Ratings*
Temperature Under Bias .................................. -40°C to +85°C
*NOTICE: Stresses beyond those listed under “Absolute
Maximum Ratings” may cause permanent dam-
age to the device. This is a stress rating only and
functional operation of the device at these or any
other conditions beyond those indicated in the
operational sections of this specification is not
implied. Exposure to absolute maximum rating
conditions for extended periods may affect device
reliability.
Note: 1. Minimum voltage is -0.6V DC, which may under-
shoot to -2.0V for pulses of less than 20 ns.
Maximum output pin voltage is V
CC
+ 0.75V DC,
which may overshoot to 7.0V for pulses of less
than 20 ns.
Storage Temperature ..................................... -65°C to +150°C
Voltage on Any Pin with
Respect to Ground .........................................-2.0V to +7.0V
(1)
Voltage on Input Pins
with Respect to Ground
During Programming.....................................-2.0V to +14.0V
(1)
Programming Voltage with
Respect to Ground .......................................-2.0V to +14.0V
(1)