2142 - [ispMACH 4000]: What is the reason behind the high supply transients during startup for the ispMACH 4000 device?

High transients during startup are because of supply sequencing used on the board, resulting in temporary leakage in the I/O buffer of the device. To minimize the transient current during power-on, configure the CPLD I/Os to a pull-up or float state. If this logic scenario is not possible, then the recommended power sequence should assert VCC and VCCO at the same time or VCC before VCCO as mentioned in the datasheet DS1022 - ispMACH 4000ZE Family. The downloadable link of the document can be found here: https://www.latticesemi.com/view_document?document_id=29095

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2142 - [ispMACH 4000]: What is the reason behind the high supply transients during startup for the ispMACH 4000 device?

2142 - [ispMACH 4000]: What is the reason behind the high supply transients during startup for the ispMACH 4000 device?

Related Articles

5461 - Why is there a high current in the device even if the device is functionally working if VCCIO is powered before Vcc?

2045 - [ispMACH 4000]: I have&nbsp;75 5V inputs&nbsp;to an ispMACH 4000&nbsp;device. Which I/O type should I use&nbsp;between LVTTL or LVTTL_5V?

3740 - ispMACH 4000: What is the difference between "External feedback" and "internal feedback" when calculating Fmax for ispMACH 4000 devices?

5411 - Why does iCE40 devices heats up and have high current consumption when VCCIO and VCCIO2 are applied before VCC?

2790 - Power manager II: Can&nbsp;we short the inputs of two VMON comparators (&nbsp;i.e. VMON1 and VMON2) of the Power Manager Device externally on the board for monitoring a supply rail&nbsp;?

2045 - [ispMACH 4000]: I have 75 5V inputs to an ispMACH 4000 device. Which I/O type should I use between LVTTL or LVTTL_5V?

2790 - Power manager II: Can we short the inputs of two VMON comparators ( i.e. VMON1 and VMON2) of the Power Manager Device externally on the board for monitoring a supply rail ?