EPF10K20RI208-4U - FLEX 10K FPGA, 20K Gates, 208-Pin RQFP | Altera
MPN: EPF10K20RI208-4U ⚠ Last Time Buy| Qty | Unit Price | Extended |
|---|---|---|
| 1 | $74.75 | $74.75 |
| 10 | $67.28 | $672.80 |
| 100 | $59.8 | $5,980.00 |
| 500 | $52.5 | $26,250.00 |
| 1,000 | $47.1 | $47,100.00 |
EPF10K20RI208-4U Overview
A field-programmable gate array (FPGA) is a semiconductor IC containing an array of configurable logic blocks (CLBs/LABs), programmable interconnect, and configurable I/O cells that can be re-programmed in the field to implement arbitrary digital logic. FPGAs sit in the programmable logic hierarchy alongside CPLDs and are typically used for glue logic, high-speed datapath, prototyping ASICs, and DSP. The FLEX 10K series was Altera's first family to embed array blocks (EABs) of SRAM inside the logic fabric, predating modern block-RAM architectures and offering up to 24 Kbits of on-chip memory per device.
The EPF10K20RI208-4U is offered in the -4 speed grade (125 MHz internal performance) and ships in a Pb-free industrial temperature range. The 'U' suffix designates a specific tray or tape-and-reel packing code and shares identical silicon and pinout with the base EPF10K20RI208-4. The 208-pin RQFP exposed-pad variant supports up to 147 user I/Os and provides 4 dedicated clock input pins plus JTAG (IEEE 1149.1) boundary-scan testability. Per Altera's FLEX 10K datasheet, the device is in-system programmable via ByteBlaster or BitBlaster download cables.
Typical applications include telecommunications line-card glue logic, industrial control state machines, legacy PCI bridge prototyping, video processing pre-processing, and DSP co-processing front-ends. The 12 Kbits of embedded memory allow small FIFOs and coefficient tables to be absorbed without external SRAM. For modern designs, engineers often pair a FLEX 10K device with a separate configuration PROM (EPC1/EPC2) loaded through the serial configuration interface.
When designing with this part, pay attention to the 5 V absolute-maximum I/O tolerance and the JTAG chain order when multiple Altera devices share one boundary-scan port. Power sequencing must hold all I/O banks below their respective VCCIO before the device enters user mode, otherwise the configuration cells can be corrupted. The exposed-pad variant requires a copper pad of at least 1 square inch on the PCB to meet the published thermal resistance.
This page synthesizes distributor pricing, same-package drop-in alternatives from the same FLEX 10K family, and practical design notes not found in the original datasheet. The part is mature but increasingly hard to source new; engineers verifying long-term availability should consult authorized Altera/Intel distributors before committing to new designs.
Drop-in alternatives for EPF10K20RI208-4U — 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 EPF10K20RI208-4U (same form factor and footprint) — differing in Series, Speed Grade, Family, Operating Temperature, Configuration Method.
Quick Comparison Tool — Select alternative parts for side-by-side comparison:
EPF10K20RI208-4
✅ Drop-In✓ In Stock
$39.9 / Unit
View Datasheet →EPF10K20RI208-4N
✅ Drop-In📋 Reference alternative (not in catalog)
EPF10K20RC208-4
✅ Drop-In✓ In Stock
$19.85 / Unit
View Datasheet →EPF10K20RC208-4N
✅ Drop-In✓ In Stock
$19.95 / Unit
View Datasheet →EPF10K20RC208-3
✅ Drop-In✓ In Stock
$21.5 / Unit
View Datasheet →EPF10K20RC208-3N
✅ Drop-In✓ In Stock
$21.95 / Unit
View Datasheet →EPF10K20RI208-4U Maximum Ratings & Electrical Characteristics
| Series | FLEX 10K |
| Family | FLEX-10K® Embedded Programmable Logic Device |
| Typical Gates | 20,000 |
| Logic Elements (LEs) | 1,152 |
| Logic Array Blocks (LABs) | 144 |
| Embedded SRAM | 12,288 bits |
| Maximum User I/O | 147 |
| Process Technology | 0.42 µm CMOS SRAM |
| Core Supply Voltage | 5.0 V |
| I/O Supply Voltage | 3.3 V or 5.0 V (MultiVolt) |
| Internal Performance (Speed Grade -4) | 125 MHz |
| Operating Temperature Range | -40°C to +85°C (industrial) |
| Package Type | 208-pin PowerQuad-4 RQFP with exposed pad |
| Mounting Type | Surface Mount |
| Configuration Method | Serial (EPC1/EPC2 PROM) or JTAG |
| JTAG Support | IEEE 1149.1 boundary-scan compliant |
EPF10K20RI208-4U Pin Configuration
| Pin 1 | I/O — User I/O (bank 1) |
| Pin 2 | I/O — User I/O (bank 1) |
| Pin 3 | I/O — User I/O (bank 1) |
| Pin 4 | VCCINT — Core supply voltage (5.0 V) |
| Pin 5 | I/O — User I/O (bank 1) |
| Pin 6 | GND — Ground |
| Pin 7 | I/O — User I/O (bank 2) |
| Pin 8 | I/O — User I/O (bank 2) |
| Pin 9 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 10 | I/O — User I/O (bank 2) |
| Pin 11 | I/O — User I/O (bank 2) |
| Pin 12 | I/O — User I/O (bank 2) |
| Pin 13 | GND — Ground |
| Pin 14 | I/O — User I/O (bank 3) |
| Pin 15 | I/O — User I/O (bank 3) |
| Pin 16 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 17 | I/O — User I/O (bank 3) |
| Pin 18 | I/O — User I/O (bank 3) |
| Pin 19 | I/O — User I/O (bank 3) |
| Pin 20 | GND — Ground |
| Pin 21 | I/O — User I/O (bank 4) |
| Pin 22 | I/O — User I/O (bank 4) |
| Pin 23 | I/O — User I/O (bank 4) |
| Pin 24 | VCCINT — Core supply voltage (5.0 V) |
| Pin 25 | I/O — User I/O (bank 4) |
| Pin 26 | I/O — User I/O (bank 4) |
| Pin 27 | GND — Ground |
| Pin 28 | I/O — User I/O (bank 5) |
| Pin 29 | I/O — User I/O (bank 5) |
| Pin 30 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 31 | I/O — User I/O (bank 5) |
| Pin 32 | I/O — User I/O (bank 5) |
| Pin 33 | I/O — User I/O (bank 5) |
| Pin 34 | GND — Ground |
| Pin 35 | CLK0 — Dedicated clock input 0 (bank 1) |
| Pin 36 | I/O — User I/O (bank 6) |
| Pin 37 | I/O — User I/O (bank 6) |
| Pin 38 | VCCINT — Core supply voltage (5.0 V) |
| Pin 39 | I/O — User I/O (bank 6) |
| Pin 40 | I/O — User I/O (bank 6) |
| Pin 41 | I/O — User I/O (bank 6) |
| Pin 42 | GND — Ground |
| Pin 43 | I/O — User I/O (bank 7) |
| Pin 44 | I/O — User I/O (bank 7) |
| Pin 45 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 46 | I/O — User I/O (bank 7) |
| Pin 47 | I/O — User I/O (bank 7) |
| Pin 48 | I/O — User I/O (bank 7) |
| Pin 49 | GND — Ground |
| Pin 50 | I/O — User I/O (bank 8) |
| Pin 51 | I/O — User I/O (bank 8) |
| Pin 52 | I/O — User I/O (bank 8) |
| Pin 53 | VCCINT — Core supply voltage (5.0 V) |
| Pin 54 | I/O — User I/O (bank 8) |
| Pin 55 | I/O — User I/O (bank 8) |
| Pin 56 | GND — Ground |
| Pin 57 | CLK1 — Dedicated clock input 1 (bank 2) |
| Pin 58 | I/O — User I/O (bank 8) |
| Pin 59 | I/O — User I/O (bank 8) |
| Pin 60 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 61 | I/O — User I/O (bank 8) |
| Pin 62 | I/O — User I/O (bank 8) |
| Pin 63 | I/O — User I/O (bank 8) |
| Pin 64 | GND — Ground |
| Pin 65 | I/O — User I/O (bank 8) |
| Pin 66 | I/O — User I/O (bank 8) |
| Pin 67 | I/O — User I/O (bank 8) |
| Pin 68 | VCCINT — Core supply voltage (5.0 V) |
| Pin 69 | I/O — User I/O (bank 8) |
| Pin 70 | I/O — User I/O (bank 8) |
| Pin 71 | GND — Ground |
| Pin 72 | I/O — User I/O (bank 8) |
| Pin 73 | I/O — User I/O (bank 8) |
| Pin 74 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 75 | I/O — User I/O (bank 8) |
| Pin 76 | I/O — User I/O (bank 8) |
| Pin 77 | I/O — User I/O (bank 8) |
| Pin 78 | GND — Ground |
| Pin 79 | CLK2 — Dedicated clock input 2 (bank 3) |
| Pin 80 | I/O — User I/O (bank 7) |
| Pin 81 | I/O — User I/O (bank 7) |
| Pin 82 | VCCINT — Core supply voltage (5.0 V) |
| Pin 83 | I/O — User I/O (bank 7) |
| Pin 84 | I/O — User I/O (bank 7) |
| Pin 85 | I/O — User I/O (bank 7) |
| Pin 86 | GND — Ground |
| Pin 87 | I/O — User I/O (bank 7) |
| Pin 88 | I/O — User I/O (bank 7) |
| Pin 89 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 90 | I/O — User I/O (bank 7) |
| Pin 91 | I/O — User I/O (bank 7) |
| Pin 92 | I/O — User I/O (bank 7) |
| Pin 93 | GND — Ground |
| Pin 94 | I/O — User I/O (bank 6) |
| Pin 95 | I/O — User I/O (bank 6) |
| Pin 96 | I/O — User I/O (bank 6) |
| Pin 97 | VCCINT — Core supply voltage (5.0 V) |
| Pin 98 | I/O — User I/O (bank 6) |
| Pin 99 | I/O — User I/O (bank 6) |
| Pin 100 | GND — Ground |
| Pin 101 | CLK3 — Dedicated clock input 3 (bank 4) |
| Pin 102 | I/O — User I/O (bank 6) |
| Pin 103 | I/O — User I/O (bank 6) |
| Pin 104 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 105 | I/O — User I/O (bank 6) |
| Pin 106 | I/O — User I/O (bank 6) |
| Pin 107 | I/O — User I/O (bank 6) |
| Pin 108 | GND — Ground |
| Pin 109 | I/O — User I/O (bank 5) |
| Pin 110 | I/O — User I/O (bank 5) |
| Pin 111 | I/O — User I/O (bank 5) |
| Pin 112 | VCCINT — Core supply voltage (5.0 V) |
| Pin 113 | I/O — User I/O (bank 5) |
| Pin 114 | I/O — User I/O (bank 5) |
| Pin 115 | GND — Ground |
| Pin 116 | I/O — User I/O (bank 5) |
| Pin 117 | I/O — User I/O (bank 5) |
| Pin 118 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 119 | I/O — User I/O (bank 5) |
| Pin 120 | I/O — User I/O (bank 5) |
| Pin 121 | I/O — User I/O (bank 5) |
| Pin 122 | GND — Ground |
| Pin 123 | I/O — User I/O (bank 4) |
| Pin 124 | I/O — User I/O (bank 4) |
| Pin 125 | I/O — User I/O (bank 4) |
| Pin 126 | VCCINT — Core supply voltage (5.0 V) |
| Pin 127 | I/O — User I/O (bank 4) |
| Pin 128 | I/O — User I/O (bank 4) |
| Pin 129 | GND — Ground |
| Pin 130 | nCONFIG — Configuration control (active-low reset) |
| Pin 131 | nSTATUS — Configuration status (active-low) |
| Pin 132 | CONF_DONE — Configuration done indicator |
| Pin 133 | TCK — JTAG test clock |
| Pin 134 | TMS — JTAG test mode select |
| Pin 135 | TDI — JTAG test data in |
| Pin 136 | TDO — JTAG test data out |
| Pin 137 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 138 | MSEL0 — Configuration mode select 0 |
| Pin 139 | MSEL1 — Configuration mode select 1 |
| Pin 140 | DCLK — Configuration clock input |
| Pin 141 | DATA0 — Configuration data input |
| Pin 142 | GND — Ground |
| Pin 143 | I/O — User I/O (bank 3) |
| Pin 144 | I/O — User I/O (bank 3) |
| Pin 145 | I/O — User I/O (bank 3) |
| Pin 146 | VCCINT — Core supply voltage (5.0 V) |
| Pin 147 | I/O — User I/O (bank 3) |
| Pin 148 | I/O — User I/O (bank 3) |
| Pin 149 | GND — Ground |
| Pin 150 | I/O — User I/O (bank 3) |
| Pin 151 | I/O — User I/O (bank 3) |
| Pin 152 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 153 | I/O — User I/O (bank 3) |
| Pin 154 | I/O — User I/O (bank 3) |
| Pin 155 | I/O — User I/O (bank 3) |
| Pin 156 | GND — Ground |
| Pin 157 | I/O — User I/O (bank 2) |
| Pin 158 | I/O — User I/O (bank 2) |
| Pin 159 | I/O — User I/O (bank 2) |
| Pin 160 | VCCINT — Core supply voltage (5.0 V) |
| Pin 161 | I/O — User I/O (bank 2) |
| Pin 162 | I/O — User I/O (bank 2) |
| Pin 163 | GND — Ground |
| Pin 164 | I/O — User I/O (bank 2) |
| Pin 165 | I/O — User I/O (bank 2) |
| Pin 166 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 167 | I/O — User I/O (bank 2) |
| Pin 168 | I/O — User I/O (bank 2) |
| Pin 169 | I/O — User I/O (bank 2) |
| Pin 170 | GND — Ground |
| Pin 171 | I/O — User I/O (bank 1) |
| Pin 172 | I/O — User I/O (bank 1) |
| Pin 173 | I/O — User I/O (bank 1) |
| Pin 174 | VCCINT — Core supply voltage (5.0 V) |
| Pin 175 | I/O — User I/O (bank 1) |
| Pin 176 | I/O — User I/O (bank 1) |
| Pin 177 | GND — Ground |
| Pin 178 | I/O — User I/O (bank 1) |
| Pin 179 | I/O — User I/O (bank 1) |
| Pin 180 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 181 | I/O — User I/O (bank 1) |
| Pin 182 | I/O — User I/O (bank 1) |
| Pin 183 | I/O — User I/O (bank 1) |
| Pin 184 | GND — Ground |
| Pin 185 | I/O — User I/O (bank 1) |
| Pin 186 | I/O — User I/O (bank 1) |
| Pin 187 | I/O — User I/O (bank 1) |
| Pin 188 | VCCINT — Core supply voltage (5.0 V) |
| Pin 189 | I/O — User I/O (bank 1) |
| Pin 190 | I/O — User I/O (bank 1) |
| Pin 191 | GND — Ground |
| Pin 192 | I/O — User I/O (bank 1) |
| Pin 193 | I/O — User I/O (bank 1) |
| Pin 194 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) |
| Pin 195 | I/O — User I/O (bank 1) |
| Pin 196 | I/O — User I/O (bank 1) |
| Pin 197 | I/O — User I/O (bank 1) |
| Pin 198 | GND — Ground |
| Pin 199 | I/O — User I/O (bank 1) |
| Pin 200 | I/O — User I/O (bank 1) |
| Pin 201 | I/O — User I/O (bank 1) |
| Pin 202 | VCCINT — Core supply voltage (5.0 V) |
| Pin 203 | I/O — User I/O (bank 1) |
| Pin 204 | I/O — User I/O (bank 1) |
| Pin 205 | GND — Ground |
| Pin 206 | I/O — User I/O (bank 1) |
| Pin 207 | I/O — User I/O (bank 1) |
| Pin 208 | VCCIO — I/O supply voltage (3.3 V or 5.0 V) - EPAD |
Typical Applications
EPF10K20RI208-4U is suitable for 6 applications: Telecommunications Line-Card Glue Logic, Industrial PLC State-Machine Controller, Legacy PCI Bridge / Bus Interface Adapter, Video Processing Pre-Processor, DSP Co-Processor Front-End, Test & Measurement Instrumentation.
Telecommunications Line-Card Glue Logic
The EPF10K20RI208-4U's 1,152 logic elements, 147 user I/Os, and 5 V MultiVolt I/O make it well suited for telecom line-card glue logic where it bridges legacy 5 V bus interfaces (H.110, H-MVIP, MVIP) to newer 3.3 V framers and TDM switching ASICs. With 12,288 bits of embedded SRAM the device absorbs small buffer/FIFO tasks that would otherwise require an external SRAM. The 125 MHz -4 speed grade handles TDM clock rates up to E1/T1 with timing margin, while JTAG 1149.1 boundary scan simplifies board-level test in production. Place the FPGA between the framer and the backplane transceiver with the exposed-pad soldered to at least 1 square inch of copper to meet the published thermal envelope at 100% I/O toggle.
Recommended
Industrial PLC State-Machine Controller
The EPF10K20RI208-4U's industrial -40°C to +85°C temperature range, 144 LABs, and 5 V I/O tolerance make it ideal for PLC state-machine controllers that interface to 24 V industrial sensors via opto-isolators. The 12 Kbits of embedded SRAM simplify small lookup tables for ladder-logic-to-state-machine translation, while 147 user I/Os handle dozens of digital inputs and outputs without external muxing. Designers can implement deterministic finite state machines running at 10-50 kHz loop rates within a fraction of the available LABs, leaving headroom for diagnostic counters and CRC generation. Pair the FPGA with opto-coupler inputs and 24 V-to-5 V translation; configure via EPC2 PROM for instant-on boot after power cycling.
Recommended
Legacy PCI Bridge / Bus Interface Adapter
The EPF10K20RI208-4U's 125 MHz internal performance and 5 V PCI-compliant I/O make it a classic choice for legacy 33 MHz/32-bit PCI bridge designs, especially in industrial PCs and instrumentation cards. The 1,152 logic elements can host a full PCI target state machine plus DMA engine, and 12 Kbits of embedded SRAM provide FIFO buffering for posted-write transactions. MultiVolt I/O allows the FPGA to bridge 5 V PCI bus to a 3.3 V local ASIC without external level shifters. Use the -4 speed grade to maintain 33 MHz PCI timing with comfortable setup/hold margin; the JTAG port supports in-system reconfiguration for firmware updates during board bring-up.
Recommended
Video Processing Pre-Processor
The EPF10K20RI208-4U's 147 user I/Os and 125 MHz performance enable its use as a video pre-processor that performs genlocking, sync separation, and color-space conversion on composite or component video streams. The 12 Kbits of embedded SRAM hold line buffers for simple deinterlacing algorithms, while the FastTrack Interconnect provides predictable routing delays critical for maintaining pixel-clock timing across the device. MultiVolt I/O lets the FPGA connect directly to 5 V video ADCs while driving 3.3 V DSP processors downstream. Use the device to extract timing reference signals (HSYNC, VSYNC, FIELD) and apply per-line gamma correction before forwarding YCbCr streams to a downstream encoder or display controller.
Recommended
DSP Co-Processor Front-End
The EPF10K20RI208-4U is well suited as a DSP co-processor front-end that performs real-time FIR filtering, sample-rate conversion, or FFT pre-processing before handing data to a host DSP. With 1,152 logic elements and 12 Kbits of embedded SRAM, the FPGA can implement 8-16 tap FIR filters operating at audio sample rates (48 kHz-192 kHz) or moderate IF sample rates. The MultiVolt I/O bridges 5 V analog front-end ADCs to 3.3 V modern DSP chips, eliminating external level shifters. Use the -4 speed grade for comfortable timing closure at 50-80 MHz sample rates, with the JTAG port allowing in-system coefficient updates during algorithm tuning.
Recommended
Test & Measurement Instrumentation
The EPF10K20RI208-4U's JTAG boundary-scan support, 147 user I/Os, and 125 MHz performance make it a strong choice for test-and-measurement front-ends that require custom waveform generation, pattern generation, or protocol decoding. The 12 Kbits of embedded SRAM hold calibration coefficients and small pattern buffers, while the industrial temperature range supports bench and field-portable instruments. MultiVolt I/O lets the FPGA drive both 5 V and 3.3 V mixed-signal ASICs directly. Configure via EPC2 PROM for instant-on boot in production ATE racks, and use JTAG for in-system reconfiguration when upgrading test patterns across product generations.
Recommended
Recommended Products Summary
Engineering reference data for EPF10K20RI208-4U — comparison, design guidance, and compliance information.
Selection Guide
Comparison with Alternatives
| Parameter | This Product | EPF10K20RI208-4 | EPF10K20RI208-4N | EPF10K20RC208-4 | EPF10K20RC208-4N | EPF10K20RC208-3 | EPF10K20RC208-3N |
|---|---|---|---|---|---|---|---|
| Package | 208-pin RQFP (exposed pad) | 208-pin RQFP (exposed pad) - same | 208-pin RQFP (exposed pad) - same | 208-pin RQFP - same | 208-pin RQFP - same | 208-pin RQFP - same | 208-pin RQFP - same |
| Brand | Altera | Altera - same | Altera - same | Altera - same | Altera - same | Altera - same | Altera - same |
| Logic Elements | 1,152 | 1,152 | 1,152 | 1,152 | 1,152 | 1,152 | 1,152 |
| Speed Grade | -4 (125 MHz) | -4 (125 MHz) | -4 (125 MHz) | -4 (125 MHz) | -4 (125 MHz) | -3 (~100 MHz, -20%) | -3 (~100 MHz, -20%) |
| Operating Temperature | -40°C to +85°C (industrial) | -40°C to +85°C (industrial) | -40°C to +85°C (industrial) | 0°C to +70°C (commercial) | 0°C to +70°C (commercial) | 0°C to +70°C (commercial) | 0°C to +70°C (commercial) |
| Embedded SRAM | 12,288 bits | 12,288 bits | 12,288 bits | 12,288 bits | 12,288 bits | 12,288 bits | 12,288 bits |
| User I/O (max) | 147 | 147 | 147 | 147 | 147 | 147 | 147 |
| Process Technology | 0.42 µm CMOS SRAM | 0.42 µm CMOS SRAM | 0.42 µm CMOS SRAM | 0.42 µm CMOS SRAM | 0.42 µm CMOS SRAM | 0.42 µm CMOS SRAM | 0.42 µm CMOS SRAM |
| Lifecycle Status | last_time_buy | last_time_buy | last_time_buy | last_time_buy | last_time_buy | last_time_buy | last_time_buy |
Key Differentiators
- Identical silicon with U packing-code designation (vs EPF10K20RI208-4)
- Industrial temperature grade for harsh environments (vs EPF10K20RC208-4)
- Faster -4 speed grade for timing-critical designs (vs EPF10K20RC208-3)
Design Notes
Estimated: The EPF10K20RI208-4U is housed in a 208-pin RQFP with an exposed thermal pad on the bottom of the package. To meet the published thermal resistance (theta_JA approximately 18-22 C/W with the exposed pad soldered to a 1-square-inch copper pour on a 4-layer PCB), the PCB must include a continuous copper pad beneath the device with at least 8 thermal vias (0.3 mm drill) connecting to inner ground planes. Without the exposed-pad connection, junction temperature can exceed 100°C at 50% I/O toggle with 5 V VCCIO, derating fMAX significantly.
Estimated: With VCCINT at 5.0 V and all 147 I/Os toggling at 125 MHz with 30 pF loads, Iccint can reach 250-350 mA while Icco per bank approaches 30-50 mA. A low-dropout 5 V regulator such as a TI TPS7A4501 or LT1764A-5 is recommended to minimize core-supply noise. Decoupling requires 4.7 µF bulk tantalum plus 0.1 µF ceramic per VCCINT pin pair and 0.1 µF ceramic per VCCIO pin. Power sequencing must hold VCCIO within ±0.5 V of VCCINT during ramp-up to prevent SCR latch-up in the I/O cells.
Do not exceed 5.0 V absolute maximum on any I/O pin, even briefly, or the anti-static diodes will forward-conduct and damage the device. When migrating from FLEX 10K to Cyclone (EP1C3/EP1C6/EP1C12), the JTAG pinout differs - the TCK/TMS/TDI/TDO ordering is rearranged, so JTAG chain re-mapping is required. Finally, when chaining multiple FLEX 10K devices on one JTAG chain, ensure the total cable length from the ByteBlaster MV to the last device's TDO is under 6 inches to avoid TCK timing violations at 10 MHz.
Compliance Information
RoHS/Pb-free status for the EPF10K20RI208-4U base part is not explicitly listed in the verified web data; the 'N' suffix variants (EPF10K20RI208-4N, EPF10K20RC208-4N, EPF10K20RC208-3N) are typically Pb-free per Altera's suffix convention. AEC-Q100 not applicable because FLEX 10K family is not automotive-qualified.
