EPM7256SQC208-7N - MAX 7000S CPLD 256 Macrocell | Altera
MPN： EPM7256SQC208-7N ✗ 停產EPM7256SQC208-7N 概覽
A CPLD (Complex Programmable Logic Device) is a programmable logic IC that combines multiple programmable logic array blocks and macrocells into a single chip, allowing designers to implement custom combinational and sequential logic without fabricating an ASIC. In the broader hierarchy, a CPLD sits between simple programmable logic devices (SPLDs/PALs) and FPGAs, offering deterministic timing, non-volatile configuration, and instant-on operation - characteristics that make it ideal for glue logic, bus interfacing, and control-path functions in embedded systems.
The MAX 7000S architecture is built around Logic Array Blocks (LABs) containing 16 macrocells each, interconnected by a programmable interconnect array (PIA). Each macrocell provides a flip-flop with programmable clock, clear, and preset, plus I/O control for tri-state, open-drain, and slew-rate settings. The EPM7256S provides 256 macrocells across 16 LABs, delivering 5,000 usable gates for moderate-complexity designs.
Key differentiators include its 7.5 ns pin-to-pin delay (the fastest -7 speed grade in the MAX 7000S family), 128.2 MHz maximum frequency, and 164 I/O pins in a 208-pin PQFP. The device supports in-system programmability (ISP) via the IEEE 1149.1 JTAG boundary-scan interface, enabling field upgrades without removing the part from the board. The EEPROM-based configuration is non-volatile, so no external configuration memory is required - a significant advantage over SRAM-based FPGAs.
Typical applications include PCI bus interfacing, ISA/VME bus glue logic, DSP/processor peripheral expansion, industrial control state machines, and telecommunications line-card control. The 5 V tolerant I/O and 3.3 V/5 V mixed-voltage operation make it suitable for legacy and mixed-voltage systems.
When designing with the EPM7256SQC208-7N, ensure adequate decoupling on each VCC pin and provide a clean JTAG chain for ISP. The 208-pin PQFP requires careful PCB layout for signal integrity at 128 MHz. This page synthesizes distributor pricing, drop-in alternatives, and practical design notes not found in the manufacturer datasheet.
直接替換替代品，適用於 EPM7256SQC208-7N — 相同封裝，腳位對腳位相容。需重新設計 PCB 的不同封裝零件不列入。
此系列的變體
與下列產品可直接替換的同系列型號： EPM7256SQC208-7N （相同外形與佔位） — 差異在於 Package, RoHS Status, Speed Grade, Operating Temperature, Pin-to-Pin Delay (tPD).
EPM7256SQC208-10N
✅ 直接替換📋 參考替代品（不在目錄中）
EPM7256SQC208-15N
✅ 直接替換聯絡詢價
查看資料表 →EPM7256SQC208-7
✅ 直接替換聯絡詢價
查看資料表 →EPM7256AEQC208-7N
✅ 直接替換📋 參考替代品（不在目錄中）
EPM7256SQC208-10
✅ 直接替換聯絡詢價
查看資料表 →EPM7256SQC208-15
✅ 直接替換聯絡詢價
查看資料表 →EPM7256SQC208-7N 最大額定值與電氣特性
| Family | MAX 7000S |
| Device Type | CPLD (Complex Programmable Logic Device) |
| Macrocells | 256 |
| Usable Gates | 5,000 |
| Logic Array Blocks (LABs) | 16 |
| User I/O Pins | 164 |
| Speed Grade | -7 (7.5 ns pin-to-pin) |
| Maximum Frequency | 128.2 MHz |
| Supply Voltage (VCC) | 5 V |
| Technology | CMOS EEPROM |
| Configuration Memory | Non-volatile EEPROM (no external config needed) |
| 封裝 | 208-pin PQFP (Plastic Quad Flat Pack) |
| 安裝類型 | Surface Mount |
| 工作溫度 | Commercial (0C to +70C) |
| JTAG Interface | IEEE 1149.1 boundary-scan (ISP capable) |
| Minimum DC Input Voltage | -0.5 V |
| Input Undershoot Tolerance | -2.0 V for <100 mA, <20 ns |
| RoHS 狀態 | Compliant (N suffix = lead-free) |
| Pin-to-Pin Delay (tPD) | 7.5 ns |
| Open-Drain Output | Optional per I/O pin |
EPM7256SQC208-7N 208-pin pqfp (plastic quad flat pack) 腳位配置指南
EPM7256SQC208-7N（208-pin pqfp (plastic quad flat pack) 封裝）的腳位配置。 此數位 IC 包含 GPIO、通訊介面（UART、SPI、I2C）與電源腳位。替代腳位功能與配置選項請參閱製造商資料表。對嵌入式系統設計與 PCB 佈局至關重要。
無詳細腳位定義資料： EPM7256SQC208-7N.
請參閱 資料表 以查看完整腳位配置。
典型應用
EPM7256SQC208-7N 適用於 6 應用s: PCI Bus Interfacing, Industrial Control State Machines, Telecommunications Line Card Control, DSP and Processor Peripheral Expansion, Legacy System Glue Logic Replacement, Test and Measurement Instrumentation.
PCI Bus Interfacing
The EPM7256SQC208-7N is well suited for PCI bus interfacing because its 7.5 ns pin-to-pin delay and 128.2 MHz maximum frequency satisfy PCI 2.2 timing requirements, while its 164 user I/O pins accommodate a 32-bit address/data bus plus control signals. The device implements bus arbitration, address decoding, and target/initiator state machines in a single non-volatile CPLD. Placed between the PCI connector and the host processor, it eliminates discrete glue logic and reduces board area. Unlike SRAM-based FPGAs, the EEPROM configuration is instant-on, so the PCI interface is ready at power-up without a configuration load cycle. The 5 V supply matches legacy PCI signaling, and JTAG ISP allows field firmware updates.
推薦
Industrial Control State Machines
In industrial automation, the EPM7256SQC208-7N implements deterministic state machines for PLCs, motor controllers, and safety interlocks. Its 256 macrocells provide enough registers for multi-state sequencing, while the 7.5 ns propagation delay ensures predictable response to sensor inputs. The non-volatile EEPROM configuration means the controller boots instantly after power loss - critical for factory floors where restart latency is unacceptable. The 5 V I/O interfaces directly with legacy 5 V sensors and actuators without level shifters. With 164 I/O pins, a single device can handle multiple axes of motion control plus safety monitoring. The commercial temperature range suits controlled-cabinet environments; for wider temperature, consider the industrial-grade variant.
推薦
Telecommunications Line Card Control
The EPM7256SQC208-7N serves as a control-plane CPLD on telecommunications line cards, managing TDM framing, clock switching, and alarm monitoring. Its 128.2 MHz maximum frequency supports high-speed serial backplane interfaces, and the 164 I/O pins connect to framers, line interface units, and the host bus. The deterministic timing of a CPLD - unlike an FPGA with variable routing delays - simplifies worst-case timing analysis for telecom equipment. The EEPROM configuration survives power cycling, so line cards resume operation immediately after a reset. The 5 V supply is compatible with legacy telecom backplanes, and JTAG ISP enables remote firmware upgrades through the backplane. Open-drain outputs allow wired-OR interrupt signaling across multiple cards.
推薦
DSP and Processor Peripheral Expansion
The EPM7256SQC208-7N expands DSP and microcontroller peripherals by implementing custom address decoding, wait-state generation, and DMA handshaking. With 256 macrocells, it can host multiple peripheral controllers - UARTs, timers, GPIO expanders - in a single device, reducing chip count. The 7.5 ns pin-to-pin delay keeps peripheral access latency low, and the 164 I/O pins match wide processor buses. Because the configuration is non-volatile, the expansion logic is available immediately at power-up, before the processor finishes booting. The 5 V I/O interfaces directly with legacy DSPs such as the TMS320C5x family. JTAG ISP allows peripheral logic updates without board rework, extending product lifetime.
推薦
Legacy System Glue Logic Replacement
The EPM7256SQC208-7N consolidates dozens of 74-series TTL glue logic packages into one CPLD, shrinking board area and improving reliability. Its 5 V supply and 5 V tolerant I/O directly replace legacy TTL without level shifting, and the 7.5 ns delay matches or exceeds discrete logic speed. The 256 macrocells absorb address decoders, bus transceivers, clock dividers, and reset logic. Because the EEPROM configuration is non-volatile, the replacement behaves like fixed logic - no boot delay, no configuration PROM. This makes the EPM7256SQC208-7N ideal for sustaining legacy industrial, medical, and aerospace systems where redesign is impractical. JTAG ISP allows logic fixes in the field, and the 208-pin PQFP footprint matches existing sockets.
推薦
Test and Measurement Instrumentation
The EPM7256SQC208-7N provides timing and control logic in test and measurement instruments such as logic analyzers, pattern generators, and ATE systems. Its 128.2 MHz maximum frequency supports high-speed data capture, while the 164 I/O pins interface with wide data buses and trigger matrices. The deterministic 7.5 ns propagation delay ensures repeatable trigger timing - essential for measurement accuracy. The non-volatile EEPROM configuration means the instrument is operational immediately at power-up, with no FPGA configuration delay. The 5 V supply matches legacy instrument backplanes, and JTAG ISP allows calibration logic updates. Open-drain outputs enable wired-OR trigger buses across multiple instrument modules.
推薦
推薦產品摘要
工程參考資料，適用於 EPM7256SQC208-7N — 比較、設計指引及合規資訊。
選型指南
與替代品比較
| 參數 | 本產品 | EPM7256SQC208-10N | EPM7256SQC208-15N | EPM7256SQC208-7 | EPM7256AEQC208-7N |
|---|---|---|---|---|---|
| Package | 208-pin PQFP | 208-pin PQFP - same | 208-pin PQFP - same | 208-pin PQFP - same | 208-pin PQFP - same |
| Brand | Altera | Altera | Altera | Altera | Altera |
| Speed Grade | -7 (7.5 ns) | -10 (10 ns) | -15 (15 ns) | -7 (7.5 ns) | -7 (7.5 ns) |
| Macrocells | 256 | 256 | 256 | 256 | 256 |
| User I/O Pins | 164 | 164 | 164 | 164 | 164 |
| Supply Voltage | 5 V | 5 V | 5 V | 5 V | 5 V |
| RoHS | Compliant (N suffix) | Compliant (N suffix) | Compliant (N suffix) | Non-compliant (no N suffix) | Compliant (N suffix) |
| Configuration Memory | EEPROM (non-volatile) | EEPROM (non-volatile) | EEPROM (non-volatile) | EEPROM (non-volatile) | EEPROM (non-volatile) |
| JTAG ISP | Yes (IEEE 1149.1) | Yes (IEEE 1149.1) | Yes (IEEE 1149.1) | Yes (IEEE 1149.1) | Yes (IEEE 1149.1) |
主要差異化特點
- Fastest speed grade in MAX 7000S family (對比EPM7256SQC208-10N)
- Non-volatile EEPROM configuration (對比EPM7256AEQC208-7N)
- RoHS-compliant lead-free package (對比EPM7256SQC208-7)
- 164 user I/O in 208-pin PQFP (對比EPM7256SQC208-15N)
設計說明
Decouple every VCC pin with a 0.1 uF ceramic capacitor placed as close to the pin as possible, plus at least one 10 uF bulk capacitor per device. The MAX 7000S family draws significant transient current during logic switching; inadequate decoupling causes ground bounce and false switching at 128 MHz. Estimated: at 5 V and 100 mA typical ICC, total power dissipation is approximately 0.5 W, but peak switching currents can be several times higher. Use a low-inductance ground plane and avoid daisy-chaining power traces between VCC pins.
The 208-pin PQFP requires careful PCB layout for signal integrity. Route high-speed signals (clock, JTAG TCK) on controlled-impedance traces and keep them away from I/O switching nodes. Provide a solid ground plane under the device and use thermal relief on the exposed pad if present. For the 128.2 MHz maximum frequency, keep trace lengths matched for bus signals and terminate long nets. Place the JTAG header close to the device to minimize TCK/TMS stub length, which improves ISP reliability.
Do not exceed the minimum DC input voltage of -0.5 V. During transitions, inputs may undershoot to -2.0 V for input currents less than 100 mA and periods shorter than 20 ns; beyond this, latch-up or damage can occur. For EPM7128A and EPM7256A devices only, VCC must rise monotonically - a non-monotonic ramp can corrupt EEPROM configuration. Always verify that the -7 speed grade timing is met after any logic change; the 7.5 ns pin-to-pin delay leaves little margin for added routing delays.
合規資訊
The N suffix indicates RoHS-compliant lead-free construction. REACH, halogen-free, and conflict-minerals status were not stated in the provided data and are marked unknown. Not AEC-Q100 qualified (commercial temperature grade).