Tool/software:
Hello TI Team,
About the Power-up Timing:
Q1:
T5.3: XTAL Startup / Settling: Powerup to XI good/stabilized
T5.4: Oscillator stabilization time from power up
What are they different?
Q2:
Could you provide the Max. Value of T5.3?
Best Regards!
Hi Jingkun,
T5.3 is for if you connect a crystal to the PHY (both XI and XO pin are used)
T5.4 is for is you connect an oscillator to the PHY (just XI pin)
T5.3 will have to stabilize before the straps latch in, and the max for Power-up to Strap latch-in is 10ms.
Best regards,
Melissa
Hi Melissa
Q3: How to measure the time of T5.6 Power-up to Strap latch-in?
Q4: How to measure below item?
Best Regards!
Hi Jingkun,
Q3: How to measure the time of T5.6 Power-up to Strap latch-in?
You can probe the power supplies and one of the strap pins on the scope. The latch in time will be the time it takes the strap pin to go from floating voltage to the strapped voltage. The strap pin you chose should be strapped to mode 2 or above.
Q4: How to measure below item?
You can measure the power supplies and the reset pin on the scope. This time will be when the last supply goes up to when reset toggles HIGH.
Best regards,
Melissa Chang
Hi Melissa:
Q3: How to measure the time of T5.6 Power-up to Strap latch-in?You can probe the power supplies and one of the strap pins on the scope. The latch in time will be the time it takes the strap pin to go from floating voltage to the strapped voltage. The strap pin you chose should be strapped to mode 2 or above.
Q1: About the Power-up to Strap latch-in Timing: which point is the Bootstrap Latch?
Q2: Using LED0 for Bootstrap Latch in timing testing, it has pulled up resistor.
From above waveform, it changed to low at last time. Is it right?
Q3: Is T6.1 necessary when PHY powers up?
Q4: T6.2's requirement is different from T5.5. T6.4's requirement is different from T5.8. Why are their requirements different?
My understand is that "Figure 7-9 Reset Timing" is suite for reset operation after power up. We don't need to consider the "Figure 7-9. Reset Timing" when PHY powers up. Is it right?
Best Regards!
Wang Jingkun
Hi Melissa:
Q3: How to measure the time of T5.6 Power-up to Strap latch-in?You can probe the power supplies and one of the strap pins on the scope. The latch in time will be the time it takes the strap pin to go from floating voltage to the strapped voltage. The strap pin you chose should be strapped to mode 2 or above.
Q1: About the Power-up to Strap latch-in Timing: which point is the Bootstrap Latch?
Q2: Using LED0 for Bootstrap Latch in timing testing, it has pulled up resistor.
From above waveform, it changed to low at last time. Is it right?
Q3: Is T6.1 necessary when PHY powers up?
Q4: T6.2's requirement is different from T5.5. T6.4's requirement is different from T5.8. Why are their requirements different?
My understand is that "Figure 7-9 Reset Timing" is suite for reset operation after power up. We don't need to consider the "Figure 7-9. Reset Timing" when PHY powers up. Is it right?
Best Regards!
Wang Jingkun
Hi Melissa:
Could you confirm below questions?
Q3: How to measure the time of T5.6 Power-up to Strap latch-in?You can probe the power supplies and one of the strap pins on the scope. The latch in time will be the time it takes the strap pin to go from floating voltage to the strapped voltage. The strap pin you chose should be strapped to mode 2 or above.
Q1: About the Power-up to Strap latch-in Timing: which point is the Bootstrap Latch?
Q2: Using LED0 for Bootstrap Latch in timing testing, it has pulled up resistor.
From above waveform, it changed to low at last time. Is it right?
Q3: Is T6.1 necessary when PHY powers up?
Q4: T6.2's requirement is different from T5.5. T6.4's requirement is different from T5.8. Why are their requirements different?
My understand is that "Figure 7-9 Reset Timing" is suite for reset operation after power up. We don't need to consider the "Figure 7-9. Reset Timing" when PHY powers up. Is it right?
Best Regards!
Wang Jingkun
Hi Jingkun,
Q3: How to measure the time of T5.6 Power-up to Strap latch-in?You can probe the power supplies and one of the strap pins on the scope. The latch in time will be the time it takes the strap pin to go from floating voltage to the strapped voltage. The strap pin you chose should be strapped to mode 2 or above.
Q1: About the Power-up to Strap latch-in Timing: which point is the Bootstrap Latch?
It is point 1. The strap latch in time is from power up to point 1.
Q2: Using LED0 for Bootstrap Latch in timing testing, it has pulled up resistor.
From above waveform, it changed to low at last time. Is it right?
Yes, this is because LED0 is also a status register that indicates link.
Q3: Is T6.1 necessary when PHY powers up?
Q4: T6.2's requirement is different from T5.5. T6.4's requirement is different from T5.8. Why are their requirements different?
My understand is that "Figure 7-9 Reset Timing" is suite for reset operation after power up. We don't need to consider the "Figure 7-9. Reset Timing" when PHY powers up. Is it right?
Q3: No.
Q4: You are correct. One set of requirements (T5) is for powering up the PHY the very first time. The second set of requirements (T6) is for toggling the RESET_N pin after the PHY has been powered on the very first time.
Best regards,
Melissa
