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Part Number AT27C256R-12RC
Manufacturer Microchip Technology
Description IC OTP 256KBIT 120NS 28SOIC
Datasheet AT27C256R-12RC Datasheet
Package 28-SOIC (0.342", 8.69mm Width)
In Stock 392 piece(s)
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Lead Time Can Ship Immediately
Estimated Delivery Time Jun 3 - Jun 8 (Choose Expedited Shipping)
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Part Number # AT27C256R-12RC (Memory) is manufactured by Microchip Technology and distributed by Heisener. Being one of the leading electronics distributors, we carry many kinds of electronic components from some of the world’s top class manufacturers. Their quality is guaranteed by its stringent quality control to meet all required standards.

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AT27C256R-12RC Specifications

ManufacturerMicrochip Technology
CategoryIntegrated Circuits (ICs) - Memory
Datasheet AT27C256R-12RCDatasheet
Package28-SOIC (0.342", 8.69mm Width)
Memory TypeNon-Volatile
Memory FormatEPROM
TechnologyEPROM - OTP
Memory Size256Kb (32K x 8)
Memory InterfaceParallel
Clock Frequency-
Write Cycle Time - Word, Page-
Access Time120ns
Voltage - Supply4.5 V ~ 5.5 V
Operating Temperature0°C ~ 70°C (TC)
Mounting TypeSurface Mount
Package / Case28-SOIC (0.342", 8.69mm Width)
Supplier Device Package28-SOIC

AT27C256R-12RC Datasheet

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Page 2

1 Features • Fast Read Access Time - 45 ns • Low-Power CMOS Operation – 100 µA max. Standby – 20 mA max. Active at 5 MHz • JEDEC Standard Packages – 28-Lead 600-mil PDIP – 32-Lead PLCC – 28-Lead TSOP and SOIC • 5V ± 10% Supply • High Reliability CMOS Technology – 2,000V 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, Industrial and Automotive Temperature Ranges Description The AT27C256R is a low-power, high-performance 262,144-bit one-time programma- ble read only memory (OTP EPROM) organized 32K by 8 bits. It requires only one 5V power supply in normal read mode operation. Any byte can be accessed in less than 45 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 only 8 mA in Active Mode and less than 10 µA in Standby. 256K (32K x 8) OTP EPROM AT27C256R Rev. 0014H–07/98 256K EPROM Pin Configurations Pin Name Function A0 - A14 Addresses O0 - O7 Outputs CE Chip Enable OE Output Enable NC No Connect TSOP Top View Type 1 1 2 3 4 5 6 7 21 20 19 18 17 16 15 14 13 12 11 10 9 8 VPP A12 A7 A6 A5 A4 A3 A10 CE O7 O6 O5 O4 O3 GND O2 O1 O0 A0 A1 A2 OE A11 A9 A8 A13 A14 VCC 22 23 24 25 26 27 28 PLCC Top View Note: PLCC Package Pins 1 and 17 are DON’T CONNECT. 5 6 7 8 9 10 11 12 13 29 28 27 26 25 24 23 22 21 A6 A5 A4 A3 A2 A1 A0 NC O0 A8 A9 A11 NC OE A10 CE O7 O6 4 3 2 1 3 2 3 1 3 0 1 4 1 5 1 6 1 7 1 8 1 9 2 0 O 1 O 2 G N D N C O 3 O 4 O 5 A 7 A 1 2 V P P N C V C C A 1 4 A 1 3 (continued) PDIP, SOIC Top View 1 2 3 4 5 6 7 8 9 10 11 12 13 14 28 27 26 25 24 23 22 21 20 19 18 17 16 15 VPP A12 A7 A6 A5 A4 A3 A2 A1 A0 O0 O1 O2 GND VCC A14 A13 A8 A9 A11 OE A10 CE O7 O6 O5 O4 O3

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AT27C256R2 The AT27C256R is available in a choice of industry stan- dard JEDEC-approved one time programmable (OTP) plastic DIP, PLCC, SOIC, and TSOP packages. All devices feature two-line control (CE, OE) to give designers the flex- ibility to prevent bus contention. With 32K byte storage capability, the AT27C256R allows firmware to be stored reliably and to be accessed by the system without the delays of mass storage media. Atmel’s 27C256R has additional features to ensure high quality and efficient production use. The Rapid™ Program- ming 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. System Considerations Switching between active and standby conditions via the Chip Enable pin may produce transient voltage excursions. Unless accommodated by the system design, these tran- sients 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 uti- lized 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. Block Diagram

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AT27C256R 3 Note: 1. Minimum voltage is -0.6V dc which may undershoot to -2.0V for pulses of less than 20 ns.Maximum output pin voltage is VCC + 0.75V dc which may overshoot to +7.0 volts for pulses of less than 20 ns. 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 Identification byte and high (VIH) to select the Device Code byte. Absolute Maximum Ratings* Temperature Under Bias................................ -55°C to +125°C *NOTICE: Stresses beyond those listed under “Absolute Maxi- mum Ratings” may cause permanent damage to the device. This is a stress rating only and func- tional operation of the device at these or any other conditions beyond those indicated in the opera- tional 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 +150°C Voltage on Any Pin with Respect to Ground .........................................-2.0V to +7.0V(1) Voltage on A9 with Respect to Ground ......................................-2.0V to +14.0V(1) VPP Supply Voltage with Respect to Ground .......................................-2.0V to +14.0V(1) Operating Modes Mode\Pin CE OE Ai VPP Outputs Read VIL VIL Ai VCC DOUT Output Disable VIL VIH X (1) VCC High Z Standby VIH X (1) X(1) VCC High Z Rapid Program(2) VIL VIH Ai VPP DIN PGM Verify(2) X(1) VIL Ai VPP DOUT Optional PGM Verify(2) VIL VIL Ai VCC DOUT PGM Inhibit(2) VIH VIH X (1) VPP High Z Product Identification(4) VIL VIL A9 = VH (3) A0 = VIH or VIL A1 - A14 = VIL VCC Identification Code

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AT27C256R4 Notes: 1. VCC must be applied simultaneously with or before VPP, and removed simultaneously with or after VPP.. 2. VPP may be connected directly to VCC, except during programming. The supply current would then be the sum of ICC and IPP. . Note: 2, 3, 4, 5. - see AC Waveforms for Read Operation. DC and AC Operating Conditions for Read Operation AT27C256R -45 -55 -70 -90 -12 -15 Operating Temp. (Case) Com. 0°C - 70°C 0°C - 70°C 0°C - 70°C 0°C - 70°C 0°C - 70°C 0°C - 70°C Ind. -40°C - 85°C -40°C - 85°C -40°C - 85°C -40°C - 85°C -40°C - 85°C -40°C - 85°C Auto. -40°C - 125°C -40°C - 125°C -40°C - 125°C -40°C - 125°C VCC Supply 5V ± 10% 5V ± 10% 5V ± 10% 5V ± 10% 5V ± 10% 5V ± 10% DC and Operating Characteristics for Read Operation Symbol Parameter Condition Min Max Units ILI Input Load Current VIN = 0V to VCC Com., Ind. ±1 µA Auto. ±5 µA ILO Output Leakage Current VOUT = 0V to VCC Com., Ind. ±5 µA Auto. ±10 µA IPP1 (2) VPP (1) Read/Standby Current VPP = VCC 10 µA ISB VCC (1) Standby Current ISB1 (CMOS), CE = VCC ± 0.3V 100 µA ISB2 (TTL), CE = 2.0 to VCC + 0.5V 1 mA ICC VCC Active Current f = 5 MHz, IOUT = 0 mA, E = VIL 20 mA VIL Input Low Voltage -0.6 0.8 V VIH Input High Voltage 2.0 VCC + 0.5 V VOL Output Low Voltage IOL = 2.1 mA 0.4 V VOH Output High Voltage IOH = -400 µA 2.4 V AC Characteristics for Read Operation Symbol Parameter Condition AT27C256R Units -45 -55 -70 -90 -12 -15 Min Max Min Max Min Max Min Max Min Max Min Max tACC (3) Address to Output Delay CE = OE = VIL 45 55 70 90 120 150 ns tCE (2) CE to Output Delay OE = VIL 45 55 70 90 120 150 ns tOE (2)(3) OE to Output Delay CE = VIL 20 25 30 30 35 40 ns tDF (4)(5) OE or CE High to Output Float, whichever occurred first 20 20 25 25 30 35 ns tOH Output Hold from Address, CE or OE, whichever occurred first 7 7 7 0 0 0 ns

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AT27C256R 5 AC Waveforms for Read Operation(1) Notes: 1. Timing measurement reference level is 1.5V for -45 and -55 devices. Input AC drive levels are VIL = 0.0V and VIH = 3.0V. Timing measurement reference levels for all other speed grades are VOL = 0.8V and VOH = 2.0V. Input AC drive levels are VIL = 0.45V and VIH = 2.4V. 2. OE may be delayed up to tCE - tOE after the falling edge of CE without impact on tCE. 3. OE may be delayed up to tACC - tOE after the address is valid without impact on tACC. 4. This parameter is only sampled and is not 100% tested. 5. Output float is defined as the point when data is no longer driven. Input Test Waveforms and Measurement Levels Output Test Load Note: 1. Typical values for nominal supply voltage. This parameter is only sampled and is not 100% tested. tR, tF < 5 ns (10% to 90%) For -45 and -55 devices only: tR, tF < 20 ns (10% to 90%) For -70, -90, -12, and -15 devices: Note: CL = 100 pF including jig capacitance, except for the -45 and -55 devices, where CL = 30 pF. Pin Capacitance f = 1 MHz, T = 25°C(1) Symbol Typ Max Units Conditions CIN 4 6 pF VIN = 0V COUT 8 12 pF VOUT = 0V

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AT27C256R6 Programming Waveforms(1) Notes: 1. The Input Timing Reference is 0.8V for VIL and 2.0V for VIH. 2. tOE and tDFP are characteristics of the device but must be accommodated by the programmer. 3. When programming the AT27C256R a 0.1 µF capacitor is required across VPP and ground to suppress spurious voltage transients. DC Programming Characteristics TA = 25 ± 5°C, VCC = 6.5 ± 0.25V, VPP = 13.0 ± 0.25V Symbol Parameter Test Conditions Limits UnitsMin Max ILI Input Load Current VIN = VIL,VIH ±10 µA VIL Input Low Level -0.6 0.8 V VIH Input High Level 2.0 VCC + 1 V VOL Output Low Volt IOL = 2.1 mA 0.4 V VOH Output High Volt IOH = -400 µA 2.4 V ICC2 VCC Supply Current (Program and Verify) 25 mA IPP2 VPP Current CE = VIL 25 mA VID A9 Product Identification Voltage 11.5 12.5 V

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AT27C256R 7 Notes: 1. VCC must be applied simultaneously or before VPP and removed simultaneously or after VPP.. 2. This parameter is only sampled and is not 100% tested. Output Float is defined as the point where data is no longer driven— see timing diagram. 3. Program Pulse width tolerance is 100 µsec ± 5%. AC Programming Characteristics TA = 25 ± 5°C, VCC = 6.5 ± 0.25V, VPP = 13.0 ± 0.25V Symbol Parameter Test Conditions(1) Limits UnitsMin Max tAS Address Setup Time Input Rise and Fall Times (10% to 90%) 20ns Input Pulse Levels 0.45V to 2.4V Input Timing Reference Level 0.8V to 2.0V Output Timing Reference Level 0.8V to 2.0V 2 µs tOES OE Setup Time 2 µs tDS Data Setup Time 2 µs tAH Address Hold Time 0 µs tDH Data Hold Time 2 µs tDFP OE High to Output Float Delay(2) 0 130 ns tVPS VPP Setup Time 2 µs tVCS VCC Setup Time 2 µs tPW CE Program Pulse Width (3) 95 105 µs tOE Data Valid from OE (2) 150 ns tPRT VPP Pulse Rise Time During Programming 50 ns Atmel’s 27C256R Integrated Product Identification Code Codes Pins Hex DataA0 O7 O6 O5 O4 O3 O2 O1 O0 Manufacturer 0 0 0 0 1 1 1 1 0 1E Device Type 1 1 0 0 0 1 1 0 0 8C

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AT27C256R8 Rapid Programming Algorithm A 100 µs CE pulse width is used to program. The address is set to the first location. VCC is raised to 6.5V and VPP is raised to 13.0V. Each address is first programmed with one 100 µs CE pulse without verification. Then a verifica- tion/reprogramming loop is executed for each address. In the event a byte fails to pass verification, up to 10 succes- sive 100 µs pulses are applied with a verification after each pulse. If the byte fails to verify after 10 pulses have been applied, the part is considered failed. After the byte verifies properly, the next address is selected until all have been checked. VPP is then lowered to 5.0V and VCC to 5.0V. All bytes are read again and compared with the original data to determine if the device passes or fails.

Page 10

AT27C256R 9 Ordering Information tACC (ns) ICC (mA) Ordering Code Package Operation RangeActive Standby 45 20 0.1 AT27C256R-45JC AT27C256R-45PC AT27C256R-45RC AT27C256R-45TC 32J 28P6 28R 28T Commercial (0°C to 70°C) 20 0.1 AT27C256R-45JI AT27C256R-45PI AT27C256R-45RI AT27C256R-45TI 32J 28P6 28R 28T Industrial (-40°C to 85°C) 55 20 0.1 AT27C256R-55JC AT27C256R-55PC AT27C256R-55RC AT27C256R-55TC 32J 28P6 28R 28T Commercial (0°C to 70°C) 20 0.1 AT27C256R-55JI AT27C256R-55PI AT27C256R-55RI AT27C256R-55TI 32J 28P6 28R 28T Industrial (-40°C to 85°C) 70 20 0.1 AT27C256R-70JC AT27C256R-70PC AT27C256R-70RC AT27C256R-70TC 32J 28P6 28R 28T Commercial (0°C to 70°C) 20 0.1 AT27C256R-70JI AT27C256R-70PI AT27C256R-70RI AT27C256R-70TI 32J 28P6 28R 28T Industrial (-40°C to 85°C) 20 0.1 AT27C256R-70JA AT27C256R-70PA AT27C256R-70RA 32J 28P6 28R Automotive (-40°C to 125°C) Package Type 32J 32-Lead, Plastic J-Leaded Chip Carrier (PLCC) 28P6 28-Lead, 0.600" Wide, Plastic Dual Inline Package (PDIP) 28R 28-Lead, 0.330" Wide, Plastic Gull Wing Small Outline (SOIC) 28T 28-Lead, Thin Small Outline Package (TSOP) (continued)

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May 26, 2020

Those components are in stock shipped fast and arrive promptly. Really Fast!


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May 18, 2020

Order arrived to Estonia in 3 days. Item as described. Well packed.


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May 3, 2020

To be honest, you're beating your competitor on delivery - sometimes I request 2nd day and you still get it here overnight. Thanks!


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Awesome components selection and availability. Ordering process is easy. They don't spam me after the purchase.


April 28, 2020

Serves its purpose. All that's needed.


April 26, 2020

Not messy and easy to handle. I've used these professionally and for my self, and they never failed me.


April 20, 2020

Great capacitors. very fast post very good communication.

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