MC34VR500 PMIC Power On Sequencing

[matthej]

Hi,

I will be using the MC34VR500V8 for powering on a LS1046. According to the datasheet, they show the turn on times of all regulators for the V1 and V2 versions.

So for V1 and V2 versions, it lists td3=1ms (delay between regulators). For the V8 version the sequencing doesn't flow like the V1 and V2 versions. (V1 and V2 have sequencing of 1, 2, 3, 4), The V8 has sequencing of  1, 4, 5, and 7.

So for the V8 version do I just multiply the sequence # by the delay? So for the second sequence (4), would be just 4X1ms?

Thanks!

[r8070z]

Regulator with sequence number N is delayed by Td2+Td3*(N-1) relative to the EN. In case of V8 the first regulator (#1) rises up in a 2.5ms after EN, the next (#4) in a 3ms after the first and so on.

[matthej]

So, wouldn't you factor in the rise time as well?

After EN:

1st one: td2+tr2 = 2.5ms +.2ms = 2.7ms

2nd one: td2+tr2 + (N-1)td3 + tr2 = 2.7ms + 3ms+.2ms = 5.9ms

etc?