Figure 182. Power-Up Sequence Recommendation for Cyclone V DevicesTo ensure the minimum current draw during device power up for Cyclone® V devices, follow the power-up sequence recommendations as shown in the following figure. Power up VCCBAT at any time. Ramp up the power rails in Group 1 to a minimum of 80% of their full rail before Group 2 starts. Power up VCCE_GXB and VCCL_GXB together with VCC .
This table lists the current transient that you may observe at the indicated power rails after powering up the Cyclone® V device, and before configuration starts. These transients have a finite duration bounded by the time at which the device enters configuration mode. For Cyclone® V SX, SE and ST devices, you may observe the current transient in the following table after powering up the device, and before all the power supplies reach the recommended operating range.
For details about the minimum current requirements, refer to the Early Power Estimator (EPE), and compare to the information listed in the following table. If the current transient exceeds the minimum current requirements in the EPE, you need to take the information into consideration for your power regulator design.
Table 117. Maximum Power Supply Current Transient and Typical Duration
Power Rail |
Maximum Power Supply Current Transient (mA) |
Typical Duration (µs) 32 |
VCCPD 33 34 |
1000 |
50 |
VCCIO 34 35 |
250 |
200 |
VCC_AUX 36 |
400 |
10 |
VCC 36 |
350 |
100 |
VCCPD_HPS 37 38 39 |
400 |
50 |
VCCIO_HPS 37 39 40 |
100 |
200 |
VCC_HPS 36 37 |
420 |
100 |
33 You may observe the current transient at
VCCPD only when you do not follow the recommended power-up sequence. To avoid the current transient at
VCCPD , follow the recommended power-up sequence.
35 You may observe the current transient at
VCCIO if you power up
VCCIO before
VCCPD . To avoid the current transient at
VCCIO , follow the recommended power-up sequence by powering up
VCCIO and
VCCPD together.
38 You may observe the current transient at
VCCPD_HPS only when you do not follow the recommended power-up sequence. To avoid the current transient at
VCCPD_HPS , follow the recommended power-up sequence.
40 You may observe the current transient at
VCCIO_HPS if you power up
VCCIO_HPS before
VCCPD_HPS . To avoid the current transient at
VCCIO_HPS , follow the recommended power-up sequence by powering up
VCCIO_HPS and
VCCPD_HPS together.