Rainbow Electronics ATF1516ASL - Manual (Page 6)

ATF1516AS(L)
6
process users may configure the device with the Power-up
Reset hysteresis set to Large or Small. Atmel POF2JED
users may select the Large option by including the flag
“-power_reset” on the command line after “filename.POF”.
To allow the registers to be properly reinitialized with the
Large hysteresis option selected, the following condition is
added:
4. If V
CC
falls below 2.0V, it must shut off com-
pletely before the device is turned on again.
When the Large hysteresis option is active, I
CC
is reduced
by several hundred microamps as well.
Security Fuse Usage
A single fuse is provided to prevent unauthorized copying
of the ATF1516AS fuse patterns. Once programmed, fuse
verify is inhibited. However, User Signature and device ID
remains accessible.
Programming
ATF1516AS devices are in-system programmable (ISP)
devices utilizing the 4-pin JTAG protocol. This capability
eliminates package handling normally required for pro-
gramming and facilitates rapid design iterations and field
changes.
Atmel provides ISP hardware and software to allow pro-
gramming of the ATF1516AS via the PC. ISP is perfomed
by using either a download cable or a comparable board
tester or a simple microprocessor interface.
To facilitate ISP programming by the Automated Test
Equipment (ATE) vendors. Serial Vector Format (SVF)
files can be created by Atmel provided software utilities.
ATF1516AS devices can also be programmed using stan-
d a r d t h i r d - p a r t y p r o g r a m m e r s . W i t h t h i r d - p a r t y
programmer, the JTAG ISP port can be disabled thereby
allowing four additional I/O pins to be used for logic.
Contact your local Atmel representatives or Atmel PLD
applications for details.
ISP Programming Protection
The ATF1516AS has a special feature that locks the device
and prevents the inputs and I/O from driving if the program-
ming process is interrupted for any reason. The inputs and
I/O default to high-Z state during such a condition. In addi-
tion the pin-keeper option preserves the former state during
device programming.
All ATF1516AS devices are initially shipped in the erased
state thereby making them ready to use for ISP.
Note: For more information refer to the “Desigining for
In-System Programmability with Atmel CPLDs”
application note.
Timing Model
U