1
Features
EE Programmable 65,536 x 1, 131,072 x 1 and 262,144 x 1 bit Serial Memories Designed
to Store Configuration Programs for Programmable Gate Arrays
Simple Interface to SRAM FPGAs Requires Only One User I/O Pin
Able to Configure with EPF6000 and EPF8000, Flex 10K FPGAs
Cascadable To Support Additional Configurations or Future Higher-Density Arrays
(17C128/256 only)
Low-Power CMOS EEPROM Process
Programmable Reset Polarity
Available in Industry-Standard Pin-Compatible PLCC Package
In-System Programmable via 2-Wire Bus
Emulation of 24CXX Serial EEPROMs
Available in 3.3V and 5V Versions
Description
The AT17C65/128/256A and AT17LV65/128/256A (AT17A Series) FPGA Configura-
tion EEPROMS (Configurator) provide an easy-to-use, cost-effective configuration
memory for Field Programmable Gate Arrays. The AT17A Series is packaged in the
popular 20-pin PLCC. The AT17A Series family uses a simple serial-access provides
to configure one or more FPGA devices. The AT17A Series organization supplies
enough memory to configure one or multiple smaller FPGAs. Using a special feature
of the AT17A Series, the user can select the polarity of the reset function by program-
ming a special EEPROM bit.
The AT17A Series is pin compatible with the industry standard configurator, and can
be programmed with industry standard programmers.
Pin Configurations
20-Pin PLCC
4
5
6
7
8
18
17
16
15
14
CLK (DCLK)
NC
NC
NC
RESET/OE (RESET/OE)
SER_EN
NC
NC
NC
NC
3
2
1
20
19
9
10
11
12
13
CE (nCS)
GND
NC
CEO (nCASC)
NC
NC
DATA
NC
VCC
NC
Rev. 0996A07/98
FPGA
Configuration
EEPROM
65K, 128K and 256K
AT17CxxxA
AT17LVxxxA
AT17A Series
2
Controlling The AT17A Series Serial EEPROMs
Most connections between the FPGA device and the serial
EEPROM are simple and self-explanatory.
The DATA output of the AT17A Series drives DIN of the
FPGA devices.
The master FPGA CCLK output drives the CLK input of
the AT17A Series.
The CEO output of any AT17C/LV128/256A drives the
CE input of the next AT17C/LV65/128/256 in a cascade
chain of PROMs.
SER_EN must be connected to V
CC
.
There are, however, two different ways to use the inputs
CE and OE, as shown in the AC Characteristics wave-
forms.
Condition 1
The simplest connection is to have the FPGA D/P output
drive both CE and RESET/OE in parallel (Figure 1). Due to
its simplicity, however, this method will fail if the FPGA
receives an external reset condition during the configura-
tion cycle. If a system reset is applied to the FPGA, it will
abort the original configuration and then reset itself for a
new configuration, as intended. Of course, the AT17A
Series does not see the external reset signal and will not
reset its internal address counters and, consequently, will
remain out of sync with the FPGA for the remainder of the
configuration cycle.
Condition 2
The FPGA D/P output drives only the CE input of the
AT17A Series, while its OE input is driven by the inversion
of the input to the FPGA RESET input pin. This connection
works under all normal circumstances, even when the user
aborts a configuration before D/P has gone high. A high
level on the RESET/OE input to the AT17C/LVxxxA dur-
ing FPGA reset clears the Configurator's internal address
pointer, so that the reconfiguration starts at the beginning.
The AT17A Series does not require an inverter since the
RESET polarity is programmable.
Block Diagram
AT17A Series
3
Pin Configurations
PLCC/S
OIC
DIP
Pin
Pin
Name
I/O
Description
2
1
DATA
I/O
Three-state DATA output for reading. Input/Output pin for programming.
4
2
CLK
I
Clock input. Used to increment the internal address and bit counter for reading and
programming.
8
3
RESET/OE
RESET/Output Enable input (when SER_EN is High). A low level on both the CE and
RESET/OE inputs enables the data output driver. A high level on RESET/OE resets both
the address and bit counters. A logic polarity of this input is programmable as either
RESET/OE or RESET/OE. This document describes the pin as RESET/OE.
9
4
CE
I
Chip Enable input. Used for device selection. A low level on both CE and OE enables the
data output driver. A high level on CE disables both the address and bit counters and
forces te device into a low-power mode. Note this pin will not enable/disable the device in
2-wire serial mode (ie; when SER_EN is low).
10
5
GND
Ground pin
12
6
CEO
O
Chip Enable Out output. This signal is asserted low on the clock cycle following the last
bit read from the memory. It will stay low as long as CE and OE are both low. It will then
follow CE until OE goes high. Thereafter, CEO will stay high until the entire PROM is
read again and senses the status of RESET polarity.
A2
I
Device selection input, A2. This is used to enable (or select) the device during
programming and when SER_EN is low (see Programming Guide for more details).
18
7
SER_EN
I
Serial enable is normally high during FPGA loading operations. Bringing SER_EN low,
enables the 2-wire serial interface for programming.
20
8
V
CC
+3.3V/+5V power supply pin.
Absolute Maximum Ratings*
Operating Temperature .................................. -55C to +125 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.
Storage Temperature ..................................... -65 C to +150C
Voltage on Any Pin
with Respect to Ground ............................. -0.1V to V
CC
+
0.5V
Supply Voltage (V
CC
) .......................................-0.5 V to + 7.0V
Maximum Soldering Temp. (10 sec. @ 1/16 in.) .............260
C
ESD (R
ZAP
= 1.5K, C
ZAP
= 100 pF)................................. 2000V
AT17A Series
4
FPGA Master Serial Mode Summary
The I/O and logic functions of the FPGA and their associ-
ated interconnections are established by a configuration
program. The program is loaded either automatically upon
power up, or on command, depending on the state of the
three FPGA mode pins. In Master Mode, the FPGA auto-
matically loads the configuration program from an external
memory. The Serial Configuration EEPROM has been
designed for compatibility with the Master Serial Mode.
Cascading Serial Configuration
EEPROMs (AT17C/LV256A)
For multiple FPGAs configured as a daisy-chain, or for
future FPGAs requiring larger configuration memories, cas-
c a d e d C o n f i g u r a t o r s p r o v i d e a d d i t i o n a l m e m o r y
(17C/LV128/256A only).
After the last bit from the first Configurator is read, the next
clock signal to the Configurator asserts its CEO output Low
and disables its DATA line. The second Configurator rec-
ognizes the low level on its CE input and enables its DATA
output.
Figure 1. Condition 1 Connection
After configuration is complete, the address counters of all
cascaded Configurators are reset if the reset signal drives
the RESET/OE on each Configurator Active.
If the address counters are not to be reset upon comple-
tion, then the RESET/OE inputs can be tied to ground. For
more details, please reference the AT17C Series Program-
ming Guide
Programming Mode
The programming mode is entered by bringing SER_EN
low. In this mode the chip can be programmed by the 2-
wire interface. The programming is done at V
CC
supply
only. Programming super voltages are generated inside the
chip. See the Programming Specification for Atmel's Con-
figuration Memories Application Note for further informa-
tion. The AT17C Series parts are read/write at 5V nominal.
The AT17LV parts are read/write at 3.0V nominal.
AT17C/LVxxx Reset Polarity
The AT17C/LVxxxA lets the user choose the reset polarity
as either RESET/OE or RESET/OE.
Standby Mode
The AT17C/LVxxxA enters a low-power standby mode
whenever CE is asserted high. In this mode, the Configura-
tor consumes less than 1.0 mA of current. The output
remains in a high-impedance state regardless of the state
of the OE input.
CS
REBOOT
M2
M1
M0
FPGA
D0
CCLK
CON
FLEX DEVICE
SERIAL
EEPROM
DATA
CLK
CE
SER_EN
RESET/OE
AT17CXX
V
CC
FLEX 10K, FLEX 16K
(CLK REQUIRED)
Operating Conditions
Symbol
Description
AT17Cxxx
AT17LVxxx
Units
Min/Max
Min/Max
V
CC
Commercial
Supply voltage relative to GND
-0
C to +70
C
4.75/5.25
3.0/3.6
V
Industrial
Supply voltage relative to GND
-40
C to +85C
4.5/5.5
3.0/3.6
V
Military
Supply voltage relative to GND
-55
C to +125C
4.5/5.5
3.0/3.6
V
AT17A Series
5
.
DC Characteristics
V
CC
= 5V
5% Commercial / 5V
10% Ind./Mil.
Symbol
Description
Min
Max
Units
V
IH
High-level input voltage
2.0
V
CC
V
V
IL
Low-level input voltage
0
0.8
V
V
OH
High-level output voltage (I
OH
= -4 mA)
Commercial
3.7
V
V
OL
Low-level output voltage (I
OL
= +4 mA)
0.32
V
V
OH
High-level output voltage (I
OH
= -4 mA)
Industrial
3.6
V
V
OL
Low-level output voltage (I
OL
= +4 mA)
0.37
V
V
OH
High-level output voltage (I
OH
= -4 mA)
Military
3.5
V
V
OL
Low-level output voltage (I
OL
= +4 mA)
0.4
V
I
CCA
Supply current, active mode
10
mA
I
L
Input or output leakage current (V
IN
= V
CC
or GND)
-10
10
A
I
CCS
Supply current, standby mode AT17C256
Commercial
75
A
Industrial/Military
150
A
Supply current, standby mode AT17C128/65
Commercial
1
mA
Industrial/Military
2
mA
DC Characteristics
V
CC
= 3.3V
10%
Symbol
Description
Min
Max
Units
V
IH
High-level input voltage
2.0
V
CC
V
V
IL
Low-level input voltage
0
0.8
V
V
OH
High-level output voltage (I
OH
= -2.5 mA)
Commercial
2.4
V
V
OL
Low-level output voltage (I
OL
= +3 mA)
0.4
V
V
OH
High-level output voltage (I
OH
= -2 mA)
Industrial
2.4
V
V
OL
Low-level output voltage (I
OL
= +3 mA)
0.4
V
V
OH
High-level output voltage (I
OH
= -2 mA)
Military
2.4
V
V
OL
Low-level output voltage (I
OL
= +2.5 mA)
0.4
V
I
CCA
Supply current, active mode
5
mA
I
L
Input or output leakage current (V
IN
= V
CC
or GND)
-10
10
A
I
CCS
Supply current, standby mode
Commercial
50
A
Industrial/Military
100
A
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