EP20K400GI655-1X - 400K Gate APEX 20K FPGA, 16640 Logic Elements, 655-Pin CPGA | Altera (Intel)
MPN: EP20K400GI655-1X ✗ End of Life| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $245 | $245.00 |
| 10 | $220 | $2,200.00 |
| 100 | $195 | $19,500.00 |
| 500 | $175 | $87,500.00 |
| 1,000 | $160 | $160,000.00 |
EP20K400GI655-1X Overview
An FPGA (Field-Programmable Gate Array) is a semiconductor integrated circuit composed of configurable logic blocks (CLBs), programmable interconnect, and I/O cells that the designer can rewire after manufacture using a hardware description language (HDL). Within the broader hierarchy, FPGAs sit between CPLDs (smaller, non-volatile) and ASICs (higher NRE cost, lower unit cost); the APEX 20K family was Altera's first to combine look-up-table logic with embedded array blocks (EABs) used for on-chip RAM, ROM, and multiplier functions. The EP20K400 sits at the top of the APEX 20K family.
The EP20K400GI655-1X delivers up to 502 user I/O lines plus 4 dedicated inputs, with a 2.5 ns pin-to-pin propagation delay window typical of the -1 speed grade. Peak reflow compatibility is rated at 220 C, and the package uses a JESD-30 code of S-CPGA-P655 (ceramic, metal-sealed co-fired, square grid array, interstitial pitch). MSL 1 indicates unlimited floor-life at less than or equal to 30 C / 85% RH before soldering, simplifying board-level handling.
Typical applications include telecommunications backplanes, multi-channel DMA controllers, custom microprocessor peripherals, and legacy ASIC-replacement designs. The 655-pin CPGA package is through-hole and socket-compatible, making the EP20K400GI655-1X suitable for prototype and low-volume production where field-upgradable logic is required.
When designing with this part, engineers should confirm Quartus or MAX+PLUS II toolchain support for the APEX 20K device family, since modern Intel Quartus releases have dropped older device support. Signal integrity on the 502 I/O requires careful power-plane decoupling and pin assignment to avoid simultaneous switching noise on the shared CPGA power pins.
Drop-in alternatives for EP20K400GI655-1X — same package, pin-to-pin compatible. Different-package parts requiring PCB rework are excluded.
Variants in this series
Same-series models that are drop-in compatible with EP20K400GI655-1X (same form factor and footprint) — differing in Package Type, Process Technology, Family, Propagation Delay, Mounting Type.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
EP20K400GI655-1
✅ Drop-In✓ In Stock
$195 / Unit
View Datasheet →EP20K400GI655-1V
✅ Drop-In✓ In Stock
$155 / Unit
View Datasheet →EP20K400GC655-1X
✅ Drop-In✓ In Stock
$193.04 / Unit
View Datasheet →EP20K400GC655-1V
✅ Drop-In✓ In Stock
$555 / Unit
View Datasheet →EP20K400GC655-2X
✅ Drop-In✓ In Stock
$175 / Unit
View Datasheet →EP20K400GC655-3X
✅ Drop-In✓ In Stock
$65 / Unit
View Datasheet →EP20K400GI655-1X Maximum Ratings & Electrical Characteristics
| Family | APEX 20K |
| Device | EP20K400 |
| Logic Elements | 16640 |
| Number of Terminals | 655 |
| User I/O Lines | 502 |
| Dedicated Inputs | 4 |
| Package Type | Ceramic Pin Grid Array (CPGA) |
| Package Code (JESD-30) | S-CPGA-P655 |
| Package Equivalence Code | SPGA655,47X47 |
| Package Body Material | CERAMIC (metal-sealed co-fired) |
| Speed Grade | -1 |
| Propagation Delay | 2.5 ns (typical for -1 grade) |
| Process Technology | CMOS, SRAM-based configuration |
| Moisture Sensitivity Level (MSL) | 1 |
| Peak Reflow Temperature | 220 C |
| Operating Temperature | -40 C to +85 C (industrial) |
| Mounting Type | Through-Hole (PGA) |
| RoHS Status | Compliant |
EP20K400GI655-1X Pin Configuration
| Pin 1 | I/O — User I/O pin (bank 1) |
| Pin 2 | I/O — User I/O pin (bank 1) |
| Pin 3 | I/O — User I/O pin (bank 1) |
| Pin 4 | I/O — User I/O pin (bank 1) |
| Pin 5 | I/O — User I/O pin (bank 1) |
| Pin 6 | VCCINT — Core supply voltage |
| Pin 7 | GND — Ground |
| Pin 8 | I/O — User I/O pin (bank 2) |
| Pin 9 | I/O — User I/O pin (bank 2) |
| Pin 10 | I/O — User I/O pin (bank 2) |
Typical Applications
EP20K400GI655-1X is suitable for 6 applications: Telecommunications Backplane Interface, Multi-Channel DMA Controller, ASIC Replacement for Industrial Control, Legacy DSP and Image Processing Pipeline, Custom Microprocessor Peripheral Hub, Avionics Legacy Interface (Non-Safety-Critical).
Telecommunications Backplane Interface
The EP20K400GI655-1X is well-suited for legacy telecom backplane interface cards where 502 user I/O pins and 16640 logic elements provide ample headroom for parallel bus aggregation across multiple T1/E1 or OC-3 channels. Its 2.5 ns propagation delay on the -1 speed grade supports the 77 MHz system clock typical of 1990s-era switch fabrics. Embedded array blocks (EABs) implement per-channel elastic buffers and protocol framing without external SRAM. The CPGA-655 package is socketed, simplifying field replacement in service-depot environments where mean-time-to-repair dominates total cost of ownership.
Recommended
Multi-Channel DMA Controller
With 16640 logic elements and embedded array blocks, the EP20K400GI655-1X can implement a multi-channel DMA controller for VMEbus or PCI host adapters in industrial computing. The 502 user I/O lines accommodate 8 to 16 independent scatter-gather engines, each with descriptor RAM resident in EABs. The -1 speed grade's 2.5 ns propagation delay closes timing at the 33 MHz PCI clock, while the industrial -40C to +85C range supports factory-floor deployment. Engineers porting legacy DMA designs should validate Quartus II 13.0 timing closure before committing to a board spin.
Recommended
ASIC Replacement for Industrial Control
Engineers use the EP20K400GI655-1X to replace obsolete ASICs in industrial control boards where the 655-pin CPGA socket footprint matches an existing PCB and a hardware re-spin is not economical. The 16640 logic elements and 16 EABs implement glue logic, custom peripherals, and small state machines in a single device. Industrial temperature operation (-40C to +85C) handles factory ambient, while MSL 1 eliminates dry-pack handling overhead during board rework. The device's CMOS SRAM configuration allows in-system re-programming via JTAG for field firmware updates.
Recommended
Legacy DSP and Image Processing Pipeline
The APEX 20K embedded array blocks on the EP20K400GI655-1X provide dedicated multiplier and RAM resources for legacy image-processing pipelines, such as those in medical imaging or industrial machine-vision controllers from the late 1990s and early 2000s. A 1024-point FFT fits comfortably in the 16640 logic elements plus 16 EABs. The 502 user I/O lines route parallel pixel data, while the -1 speed grade sustains 50 MHz pixel clocks for standard-definition video. New designs should consider migrating to a Cyclone V or Lattice ECP5 with a similar EAB structure for active toolchain support.
Recommended
Custom Microprocessor Peripheral Hub
The EP20K400GI655-1X serves as a custom peripheral hub for legacy PowerPC or MIPS host processors, providing glueless bridging between the host bus and 8 to 12 peripheral interfaces (UART, timers, GPIO, custom FIFOs). The 502 I/O accommodates the bus plus peripherals without external muxing. EABs implement per-peripheral FIFOs and configuration registers, while general logic elements handle address decoding and interrupt steering. The CPGA-655 socket simplifies engineering bring-up and lets engineers swap prototypes quickly during firmware development cycles.
Recommended
Avionics Legacy Interface (Non-Safety-Critical)
Non-safety-critical avionics subsystems, such as in-flight entertainment controllers or cabin-management networks, historically used the EP20K400GI655-1X because the -1V variant's +100C ceiling tolerates avionics bay ambient. The 16640 logic elements implement ARINC 429 and MIL-STD-1553 protocol engines, while the 502 I/O route multiple bus channels. The ceramic CPGA package withstands vibration better than plastic BGA alternatives, an important factor for airborne mechanical environments. Note that for new DO-254 safety-critical designs, an active-lifecycle FPGA such as Microsemi/Microchip PolarFire is now the regulatory baseline.
Recommended
Recommended Products Summary
Engineering reference data for EP20K400GI655-1X — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | EP20K400GI655-1 | EP20K400GI655-1V | EP20K400GC655-1X | EP20K400GC655-2X |
|---|---|---|---|---|---|
| Package | CPGA-655 (SPGA655,47X47) | CPGA-655 - same | CPGA-655 - same | CPGA-655 - same | CPGA-655 - same |
| Brand | Altera (Intel) | Altera (Intel) | Altera (Intel) | Altera (Intel) | Altera (Intel) |
| Logic Elements | 16640 | 16640 | 16640 | 16640 | 16640 |
| Speed Grade | -1 (fastest) | -1 | -1 | -1 | -2 (slower) |
| Operating Temperature | -40C to +85C (industrial) | 0C to +85C (commercial) | -40C to +100C (extended) | -40C to +85C (industrial) | -40C to +85C (industrial) |
| User I/O | 502 | 502 | 502 | 502 | 502 |
| Dedicated Inputs | 4 | 4 | 4 | 4 | 4 |
Key Differentiators
- Industrial temperature grade at the -1 speed grade (vs EP20K400GI655-1)
- Industrial temperature envelope within standard -1X speed grade family (vs EP20K400GI655-1V)
- Original GI process revision with established die (vs EP20K400GC655-1X)
Design Notes
The ceramic CPGA-655 package dissipates heat primarily through the pin grid into the PCB; for sustained high-utilization designs (>80% logic element activity at 50 MHz), plan at least 2 oz copper inner planes with thermal vias under the package cavity. Forced-air cooling is recommended for closed enclosures. The 220 C peak reflow rating allows lead-bearing assembly processes compatible with RoHS exemption Annex III 7a/7c-I for large ceramic packages.
Use a PGA socket (e.g., Yamaichi IC179-655 or equivalent) to allow field replacement and prototype rework. Place decoupling capacitors (0.1 uF X7R per VCCINT pin pair, plus 10 uF tantalum per VCCIO bank) within 5 mm of the package pins. Maintain continuous ground planes on layer 2 and a dedicated VCCINT island on layer 3 to minimize SSO noise across the 502 I/O. JTAG pins (TCK, TMS, TDI, TDO, TRST) require 10 kohm pull-ups to VCCIO for stable boundary-scan operation.
Do not assume modern Quartus Prime supports the APEX 20K family - it was dropped after Quartus II 13.0. New bitstream generation requires a legacy MAX+PLUS II or Quartus II 13.0 install running on Windows 7 / Windows Server 2008 or a virtual machine. Configuration file (.sof or .pof) generation from RTL must use the older synthesis flow. Also note that the APEX 20K configuration scheme uses dedicated configuration pins (nSTATUS, CONF_DONE, nCONFIG, DCLK) which must be properly pulled during power-up; misconfiguration here prevents the device from entering user mode.
Compliance Information
RoHS compliance is via exemption (ceramic PGA with lead-bearing terminations). Halogen-free status not stated by manufacturer. Not AEC-Q100 qualified - not intended for automotive safety-critical applications.
