ZHCSP07A October 2021 – October 2024 ADC12DJ800 , ADC12QJ800 , ADC12SJ800
PRODUCTION DATA
The 1.1-V supplies (VA11, VD11) must not be more than 0.5 V above any of the 1.9-V supplies (VA19, VPLL19, VREFO) or VTRIG (1.1 V or 1.9 V) during power up, normal operation or power down. Further, all 1.9 V supplies should be within 0.5 V of each other at all times. VTRIG can be ramped with either the 1.9-V supplies or 1.1-V supplies, but must not be less than 0.5 V below VA11 or VD11 at any time. There is no sequencing requirement between VA11 and VD11.
The general recommendation is to have all 1.9-V supplies share a regulator. VTRIG is generally either 1.1 V or 1.9 V and should share a regulator with supplies of the same voltage. The sequencing requirement can then generally be met by tying the power good output of the 1.9-V regulator to the 1.1-V regulator(s). This specifies that the 1.1-V supplies are enabled after the 1.9-V supplies have come up (power is good) and that the 1.9-V supplies are always greater than the 1.1-V supplies on power up. During power down as soon as the 1.1-V supplies drop out of regulation then the 1.9-V supplies are disabled. The ramp rates must be designed such that the 1.9-V supplies never dip more than 0.5 V below the VA11 or VD11 supply.