Supervisory Devices: Complementary Parts Guide for Altera FPGAs

Time: 2025-01-03 10:51:21View:

Supervisory devices are essential components that monitor and ensure the proper operation of Altera FPGAs (now part of Intel FPGA product lines). These devices handle critical tasks such as power sequencing, voltage monitoring, reset generation, and watchdog timing to ensure FPGA stability and reliability.

1. Key Functions of Supervisory Devices for FPGAs

1. Power Supply Monitoring: Ensure power supply rails are within operating ranges.

2. Reset Generation: Provide clean and reliable reset signals during power-up, brown-out, or failure events.

3. Watchdog Timer: Restart or reset the FPGA if it becomes unresponsive.

4. Voltage Sequencing: Manage the order in which power rails are activated.

5. Over-Temperature Protection: Monitor system temperature and prevent overheating damage.

2. Common Supervisory Device Types

Device Type	Function	Examples
Voltage Supervisors	Monitor voltage rails & generate reset	ADM13305, LTC2937
Reset Generators	Generate reset signals	MAX706, ADM8317
Watchdog Timers	Reset FPGA if unresponsive	MAX6326, ADM8318
Sequencers	Control power-on sequence of rails	LTC2928, ADM1186
Temperature Monitors	Monitor FPGA temperature & act if exceeded	TMP461, MAX1619

3. Integration with Altera FPGA Families

Recommended Supervisory Devices for FPGA Families:

Altera FPGA Family	Voltage Supervisor	Reset Controller	Power Sequencer	Temperature Sensor
Cyclone V	ADM13305	MAX706	ADM1186	TMP461
Arria V	LTC2937	ADM8317	LTC2928	MAX1619
Stratix V	LTC2991	ADM6326	LTC2978	TMP451
MAX 10	MAX1617	MAX6369	ADM1184	TMP102

Note: Always check the FPGA family datasheet for specific voltage rail requirements and compatibility with supervisory devices.

4. Common Circuit Configuration for FPGA Supervision

a. Voltage Supervisor Circuit:

· Monitors VCCINT, VCCIO, and VCCA voltages.

· Generates a reset signal if voltage goes out of acceptable ranges.

Example Devices: ADM13305, LTC2937

b. Reset Controller Circuit:

· Provides a clean reset signal during power-up and power-down.

· Prevents FPGA from starting in an unstable state.

Example Devices: MAX706, ADM8317

c. Watchdog Timer:

· FPGA toggles a signal periodically to reset the watchdog timer.

· If the signal stops toggling, the watchdog resets the FPGA.

Example Devices: MAX6326, ADM8318

d. Power Sequencer Circuit:

· Ensures proper power-up sequence of voltage rails.

· Prevents damage due to improper sequencing.

Example Devices: LTC2928, ADM1186

5. Design Best Practices for FPGA Supervision

1. Voltage Tolerance: Ensure the supervisor matches the voltage thresholds of the FPGA.

2. Reset Timing: Verify the reset signal timing meets FPGA specifications.

3. Watchdog Configuration: Adjust watchdog timeout appropriately for your FPGA design.

4. Thermal Management: Include temperature sensors for thermal protection.

5. Redundancy: Consider using multiple supervisors for critical applications.

6. Resources for FPGA and Supervisory Integration

· Intel FPGA Documentation: Intel FPGA Documentation Portal

· Analog Devices Supervisory ICs: Analog Devices Supervisory ICs

· Texas Instruments (TI) Supervisory ICs: TI Supervisory Circuits