Features
•Fast Read Access Time - 70 ns
•Low Power CMOS Operation 100 μA max. Standby
30 mA max. Active at 5 MHz
•JEDEC Standard Packages
32-Lead 600-mil PDIP
32-Lead 450-mil SOIC (SOP)
32-Lead PLCC
32-Lead TSOP
•5V ± 10% Supply
•High Reliability CMOS Technology 2000V ESD Protection
200 mA Latchup Immunity
•Rapid™ Programming Algorithm - 100 μs/byte (typical)
•CMOS and TTL Compatible Inputs and Outputs
•Integrated Product Identification Code
•Commercial and Industrial Temperature Ranges
Description
The AT27C040 chip is a low-power, high-performance, 4,194,304-bit one-time programmable read only memory (OTP EPROM) organized as 512K by 8 bits. The AT27C040 requires only one 5V power supply in normal read mode operation. Any byte can be accessed in less than 70 ns, eliminating the need for speed reducing WAIT states on high-performance microprocessor systems.
Atmel's scaled CMOS technology provides low active power consumption, and fast programming. Power consumption is typically 8 mA in active mode and less than 10
μA in standby mode.
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Pin Configurations
PDIP, SOIC Top View
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Pin Name |
Function |
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A0 - A18 |
Addresses |
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O0 - O7 |
Outputs |
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Chip Enable |
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CE |
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Output Enable |
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OE |
PLCC Top View
TSOP Top View
AT27C040
4-Megabit
(512K x 8) OTP EPROM
AT27C040
0189E-A–7/97
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The AT27C040 is available in a choice of industry standard JEDEC-approved one-time programmable (OTP) plastic PDIP, PLCC, SOIC (SOP), and TSOP packages. The device features two-line control (CE, OE) to eliminate bus contention in high-speed systems.
Atmel's AT27C040 has additional features to ensure high quality and efficient production use. The Rapid™ Programming Algorithm reduces the time required to program the part and guarantees reliable programming. Programming time is typically only 100 μs/byte. The Integrated Product Identification Code electronically identifies the device and manufacturer. This feature is used by industry standard programming equipment to select the proper programming algorithms and voltages.
Switching Considerations
Switching between active and standby conditions via the Chip Enable pin may produce transient voltage excursions. Unless accommodated by the system design, these transients may exceed data sheet limits, resulting in device non-conformance. At a minimum, a 0.1 μF high frequency, low inherent inductance, ceramic capacitor should be utilized for each device. This capacitor should be connected between the VCC and Ground terminals of the device, as close to the device as possible. Additionally, to stabilize the supply voltage level on printed circuit boards with large EPROM arrays, a 4.7 μF bulk electrolytic capacitor should be utilized, again connected between the VCC and Ground terminals. This capacitor should be positioned as close as possible to the point where the power supply is connected to the array.
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AT27C040 |
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AT27C040
Block Diagram
Operating Modes
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Mode/Pin |
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CE |
OE |
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Ai |
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VPP |
Outputs |
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Read |
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V |
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V |
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Ai |
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X(1) |
D |
OUT |
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IL |
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IL |
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Output Disable |
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X |
VIH |
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X |
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X |
High Z |
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Standby |
VIH |
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X |
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X |
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X |
High Z |
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Rapid Program(2) |
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V |
V |
IH |
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Ai |
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V |
D |
IN |
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IL |
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PP |
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PGM Verify |
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X |
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VIL |
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Ai |
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VPP |
DOUT |
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PGM Inhibit |
VIH |
VIH |
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X |
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VPP |
High Z |
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Product Identification(4) |
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A9 = VH(3) |
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V |
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V |
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A0 = V or V |
IL |
X |
Identification Code |
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IL |
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IL |
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IH |
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A1 - A18 = VIL |
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Notes: 1. X can be VIL or VIH.
2.Refer to Programming Characteristics
3.VH = 12.0 ± 0.5V.
4.Two identifier bytes may be selected. All Ai inputs are held low (VIL), except A9 which is set to VH and A0 which is toggled low (VIL) to select the Manufacturer’s Identificaton byte and high (VIH) to select the Device Code byte.
Absolute Maximum Ratings*
Temperature Under Bias |
......................-55°C to +125°C |
Storage Temperature............................ |
-65°C to +150°C |
Voltage on Any Pin with |
-2.0V to +7.0V (1) |
Respect to Ground .............................. |
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Voltage on A9 with |
- 2.0V to +14.0V (1) |
Respect to Ground ........................... |
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VPP Supply Voltage with |
- 2.0V to +14.0V (1) |
Respect to Ground ............................ |
*NOTICE: Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage 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.
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