10CL040YF484 Programming fails

Hi Suvarna,

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1. Power Sequencing — Is it Required?

No, power sequencing is not required for Cyclone 10 LP.

Cyclone 10 LP devices support power up or power down of the VCCINT, VCCA, and VCCIO pins in any sequence to simplify the system level design. Altera Cyclone 10 LP Device Design GuidelinesNo special power up or down sequence control is required, because the Cyclone 10 LP FPGA can be powered up and down in any sequence. Cyclone 10 LP FPGA Evaluation Kit User Guide

Power sequencing is not applicable for Cyclone 10 LP devices. Altera Cyclone 10 LP Device Design Guidelines

You can drive signals into the I/O pins before or during power up or power down without damaging the device. Altera Cyclone 10 LP Device Design Guidelines

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2. Power Supply Voltages for Your Device

The three main rails and their nominal voltages are:

VCCINT: 1.0 V or 1.2 V (core voltage power supply). Cyclone 10 LP Core Fabric and General Purpose I/Os Handbook All VCCINT pins must be connected to either a 1.0 V supply or a 1.2 V supply. Cyclone 10 LP devices with VCCINT 1.0 V and Cyclone 10 LP devices with VCCINT 1.2 V have different ordering codes. Cyclone 10 LP Device Family Pin Connection Guidelines

VCCA: 2.5 V nominal (PLL analog power supply). Cyclone 10 LP Core Fabric and General Purpose I/Os Handbook

VCCIO: 1.2, 1.5, 1.8, 2.5, 3.0, or 3.3 V (I/O banks power supply), depending on your I/O standard. Cyclone 10 LP Core Fabric and General Purpose I/Os Handbook

For VCCD_PLL (digital PLL supply): These are the digital power pins for PLLs[1..4]. You must power up these pins even if the PLL is not used. They are required to be connected to either 1.0 V (if VCCINT is 1.0 V) or 1.2 V (if VCCINT is 1.2 V). Cyclone 10 LP Device Family Pin Connection Guidelines

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3. Power Ramp Requirements (what IS mandatory)

Although sequencing is free, the ramp itself has rules:

The individual power supply ramp-up and ramp-down rates can range from 50 µs to 50 ms. The power ramp must be monotonic. Altera Cyclone 10 LP Device Design Guidelines

When power is applied to a Cyclone 10 LP device, a POR event occurs if the power supply reaches the recommended operating range within a certain period of time (specified as a maximum power supply ramp time; tRAMP). The maximum power supply ramp time for Cyclone 10 LP devices is 50 ms for standard POR or 3 ms for fast POR, while the minimum power supply ramp time is 50 µs. Altera Cyclone 10 LP Device Design Guidelines

In Cyclone 10 LP devices, you can select a fast or standard POR time, depending on the MSEL pin settings. The fast POR time is 3 ms < TPOR < 9 ms for a fast configuration time. The standard POR time is 50 ms < TPOR < 200 ms, which has a lower power-ramp rate. Altera Cyclone 10 LP Device Design Guidelines

After power up, the device does not release nSTATUS until VCCINT, VCCA, and VCCIO for the I/O banks that contain configuration pins are above the POR trip point of the device. Altera Cyclone 10 LP Device Design Guidelines

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4. JTAG Board Bring-Up Checklist (common failure points)

If you're seeing JTAG scan failures, check these items:

A device operating in JTAG mode uses four required pins — TDI, TDO, TMS, and TCK. The TCK pin has an internal weak pull-down resistor, while the TDI and TMS pins have weak internal pull-up resistors. Altera Cyclone 10 LP Device Design Guidelines

Connect TCK through a 1 kΩ pull-down resistor to GND. To disable the JTAG circuitry entirely, connect TCK to GND. Cyclone 10 LP Device Family Pin Connection Guidelines

JTAG pins in the Cyclone 10 LP device are powered up by VCCIO. However, you may need to use VCCA in some cases. Altera Cyclone 10 LP Device Design Guidelines

In single device configuration and JTAG programming, nCE should be connected to GND. Cyclone 10 LP Device Family Pin Connection Guidelines

Noise on the JTAG pins during configuration, user mode, or power-up can cause the device to go into an undefined state or mode. Altera Cyclone 10 LP Device Design Guidelines

You might have to add buffers to a JTAG chain, depending on the JTAG signal integrity, especially the TCK signal, because it is the JTAG clock and the fastest switching JTAG signal. Altera recommends buffering the signals at the connector because cables and board connectors tend to make bad transmission lines and introduce noise to the signals. Altera Cyclone 10 LP Device Design Guidelines

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Summary / Final Conclusion for 10CL040YF484:

✅ No power sequencing required — bring up VCCINT, VCCA, VCCIO in any order.

✅ Ramp must be monotonic, between 50 µs and 50 ms (standard POR) or 3 ms (fast POR).

✅ VCCA = 2.5 V (±3% ripple max if using a switcher); VCCINT = 1.0 V or 1.2 V per your specific ordering code variant.

✅ VCCD_PLL must be powered even if PLLs are unused.

✅ For JTAG: pull TCK low (1 kΩ to GND), pull TMS/TDI high, tie nCE to GND for single-device use.