13

ATF1508AS(L)

0784P–PLD–7/05

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:

2. Pin or product term.

Power-down AC Characteristics(1)(2)

Symbol

Parameter

-7

-10

-15

-20

-25

Units

Min

Max

Min

Max

Min

Max

Min

Max

Min

Max

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

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

1215253035

ns

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

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.

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

Voltage on Input Pins

with Respect to Ground

Programming Voltage with