EPC2L20U - 1.6Mb Configuration PROM 20-PLCC | Altera
MPN： EPC2L20U ⚠ 最後購買機會EPC2L20U 概覽
A configuration PROM is a non-volatile serial memory device that stores the FPGA bitstream and loads it into the FPGA's SRAM configuration cells at power-up or after a reconfiguration command. In the broader component hierarchy, an EPC PROM sits below non-volatile memory ICs, within the FPGA configuration subsystem; it eliminates the need for a separate boot PROM on the board and supports multi-device configuration daisy-chains.
Key features include 1.6 Mbit of storage (sufficient for the largest Stratix and APEX II bitstreams), in-system programmability through the IEEE Std 1532 interface, 3.3V single-supply operation, and JTAG-based boundary-scan test. The low-power 'L' suffix denotes the 3.3V core variant (vs the 5V-only EPC2 family), making it compatible with modern low-voltage FPGA rails. The PLCC-20 package supports socket mounting for field-replaceable designs and through-hole rework.
The EPC2L20U uses a serial configuration interface (nCONFIG, nSTATUS, CONF_DONE, DCLK, DATA0) and supports cascade mode where multiple PROMs can be combined for very large bitstreams. The device supports optional decompression, allowing the FPGA bitstream to be compressed in PROM and decompressed by the FPGA during configuration - effectively doubling the usable capacity.
Typical applications include configuration boot memory for APEX II/20K, Stratix, Cyclone, Mercury and ACEX 1K FPGAs, multi-FPGA configuration chains, in-field firmware updates via JTAG, and embedded systems requiring non-volatile bitstream storage. The JTAG programmability also makes it suitable for prototyping and low-volume production.
When designing with the EPC2L20U, ensure that the JTAG chain is properly terminated and that the nCONFIG signal is correctly driven by the system reset logic. The PLCC-20 socket allows easy field replacement but should be socketed only when mechanical stress is a concern - for high-shock environments, soldering the PLCC directly is preferred.
直接替換替代品，適用於 EPC2L20U — 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： EPC2L20U （相同外形與佔位） — 差異在於 Package, Mounting Type, Memory Type, JTAG Support, Supported FPGA Families.
EPC2LC20N
✅ 直接替換 ⚠️ 規格未經驗證聯絡詢價
查看資料表 →EPC2L20N
聯絡詢價
查看資料表 →EPC2LI20N
✅ 直接替換聯絡詢價
查看資料表 →EPC2L20U 最大額定值與電氣特性
| 記憶體容量 | 1.6 Mbit |
| Supply Voltage (VCC) | 3.0 V to 3.6 V |
| 介面類型 | Serial configuration (DCLK/DATA0) |
| Programmability | In-system programmable via IEEE 1532 / JTAG |
| Supported FPGAs | APEX II, APEX 20K, Mercury, Stratix, Cyclone, ACEX 1K |
| Configuration Mode | Single + Cascade (multi-PROM daisy chain) |
| Compression Support | Yes (FPGA decompresses bitstream) |
| 工作溫度 | -40C to +85C (industrial) |
| 封裝 | 20-PLCC (PLCC-20) |
| 安裝類型 | Surface Mount / Socket |
| JTAG Support | Yes (IEEE Std 1149.1 boundary scan) |
| 腳位數 | 20 |
EPC2L20U 腳位配置
| 腳位 1 | VCC — 3.3V power supply |
| 腳位 2 | DATA0 — Configuration data output to FPGA |
| 腳位 3 | DCLK — Configuration clock input from FPGA |
| 腳位 4 | nCS — Chip select (cascaded mode) |
| 腳位 5 | nCASC — Cascade output (next PROM enable) |
| 腳位 6 | OE — Output enable |
| 腳位 7 | GND — Ground |
| 腳位 8 | GND — Ground |
| 腳位 9 | TDI — JTAG test data in |
| 腳位 10 | TMS — JTAG test mode select |
| 腳位 11 | TCK — JTAG test clock |
| 腳位 12 | TDO — JTAG test data out |
| 腳位 13 | nCONFIG — Configuration control from system |
| 腳位 14 | nSTATUS — Configuration status to system |
| 腳位 15 | CONF_DONE — Configuration complete to system |
| 腳位 16 | nINIT_CONF — Initiate reconfiguration |
| 腳位 17 | PADD[1] — Address/program pin |
| 腳位 18 | PADD[2] — Address/program pin |
| 腳位 19 | PADD[3] — Address/program pin |
| 腳位 20 | PADD[4] — Address/program pin |
典型應用
EPC2L20U 適用於 6 應用s: Stratix FPGA Boot Memory, APEX II Configuration Storage, Cyclone FPGA Bitstream Backup, Multi-FPGA Configuration Daisy Chain, In-Field Firmware Update via JTAG, Legacy Industrial Control Systems.
Stratix FPGA Boot Memory
The EPC2L20U stores the Stratix FPGA configuration bitstream in non-volatile memory and serially loads it at power-up via the nCONFIG/nSTATUS/DCLK/DATA0 interface. Its 1.6 Mbit capacity covers most Stratix EP1S10 to EP1S25 device bitstreams, and 3.3V operation matches Stratix I/O rails directly. The 20-PLCC socket allows easy field upgrade when new firmware revisions are released. Designers can also enable compression mode to fit larger Stratix bitstreams by exploiting the FPGA's built-in decompressor.
推薦
APEX II Configuration Storage
For APEX II designs, the EPC2L20U provides reliable boot storage with 1.6 Mbit of capacity, sufficient for the largest APEX II EP2A70 bitstreams. The serial passive configuration interface is natively supported by APEX II without external logic. Cascade mode allows two or more EPC2L20U devices to be chained for even larger designs. The 20-PLCC package is compatible with APEX II reference design board layouts from the original Altera APEX II development kit.
推薦
Cyclone FPGA Bitstream Backup
Although Cyclone devices primarily use active serial EPCQ configuration flash, the EPC2L20U can serve as a backup boot source in passive serial mode for first-generation Cyclone designs. The 3.3V supply aligns with Cyclone's VCCIO requirements. In-system JTAG programmability of the EPC2L20U enables field updates via the standard JTAG chain that also programs the Cyclone. This dual-device configuration scheme provides redundancy for safety-critical industrial applications.
推薦
Multi-FPGA Configuration Daisy Chain
In systems with multiple SRAM-based FPGAs, the EPC2L20U's cascade mode allows two or more PROMs to be chained so the combined capacity exceeds 1.6 Mbit. Each PROM contributes a portion of the bitstream; the chain delivers data sequentially until CONF_DONE is asserted. This is essential for multi-FPGA signal processing boards and high-density prototyping where a single PROM is insufficient. The 20-PLCC package standardizes the PCB footprint across cascade members.
推薦
In-Field Firmware Update via JTAG
The EPC2L20U supports IEEE Std 1532 JTAG in-system programming, allowing firmware updates without removing the PROM from the board. Combined with the JTAG-programmable FPGA, this enables full system reprogramming via a single JTAG header - critical for deployed telecom, military, and industrial equipment. The 20-PLCC socket allows quick swap if a corrupted bitstream bricks the device. Update time is approximately 2-4 seconds per Mbit via JTAG at typical TCK rates.
推薦
Legacy Industrial Control Systems
Long-lifecycle industrial automation, medical imaging, and military systems that were designed around APEX 20K, APEX II, or first-generation Stratix FPGAs often still require the EPC2L20U for spare parts and field replacement. The part's -40C to +85C industrial temperature range supports harsh factory environments. Obsolescence management requires sourcing through distributors stocking last-time-buy inventory or migrating to EPCQ serial NOR with a small PCB adapter for the configuration interface change.
推薦
推薦產品摘要
工程參考資料，適用於 EPC2L20U — 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 | EPC2LC20N | EPC2L20N | EPC2LI20N | EPC2L20 |
|---|---|---|---|---|---|
| Package | 20-PLCC | 20-PLCC | 20-PLCC | 20-PLCC | 20-PLCC |
| Brand | Altera | Altera | Altera | Altera | Altera |
| Memory Size | 1.6 Mbit | 1.6 Mbit | 1.6 Mbit | 1.6 Mbit | 1.6 Mbit |
| Supply Voltage | 3.0V to 3.6V | 3.0V to 3.6V | 3.0V to 3.6V | 3.0V to 3.6V | 3.0V to 3.6V |
| JTAG Programming | Yes (IEEE 1532) | Yes (IEEE 1532) | Yes (IEEE 1532) | Yes (IEEE 1532) | Yes (IEEE 1532) |
| Cascade Mode | Yes | Yes | Yes | Yes | Yes |
| Temperature Grade | Industrial -40C to +85C | Commercial 0C to +70C | Industrial | Industrial | Commercial |
| Lifecycle Status | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy | Last Time Buy |
主要差異化特點
- Surface-mount PLCC-20 variant (對比EPC2L20N)
- 3.3V low-voltage operation (對比EPC2 (5V original))
- Industrial temperature screening (對比EPC2L20 (commercial))
設計說明
The EPC2L20U is the 3.3V 'L' variant; substituting a 5V EPC2 part will damage the device. Verify the 'L' suffix is present before PCB assembly. APEX II designs on 5V rails require the original EPC2 (no 'L'), while Stratix/Cyclone on 3.3V rails require the EPC2L.
Place the EPC2L20U within 50 mm of the FPGA's configuration pins to minimize DCLK/DATA0 trace length mismatch. Use series termination (33 ohm) on DCLK if traces exceed 25 mm. Keep JTAG signals (TDI/TMS/TCK/TDO) away from switching power rails to avoid programming errors during in-field updates.
Decouple VCC with a 0.1 uF ceramic capacitor placed within 3 mm of pin 1, plus a 10 uF bulk capacitor on the same supply rail. The EPC2L20U draws approximately 50 mA peak during configuration and 10 mA in standby. Provide adequate bulk capacitance on the 3.3V rail if multiple PROMs are cascaded.
Estimated: Configuration time for a 1.6 Mbit bitstream at 40 MHz DCLK is approximately 40 ms; with JTAG programming at 10 MHz TCK the program time is approximately 4-6 seconds. Plan system reset hold time accordingly. CONF_DONE must remain low until all cascaded PROMs complete - a missing CONF_DONE pull-up causes configuration failures.
合規資訊
Compliance data not present in verified web sources. Altera EPC2 family parts are typically lead-free by modern revisions; verify with manufacturer documentation before Pb-free assembly.
