
Spartan-3E FPGA Family: DC and Switching Characteristics
DS312 (v4.1) July 19, 2013
Product Specification
116
Power Supply Specifications
Table 74: Supply Voltage Thresholds for Power-On Reset
Symbol
Description
Min
Max
Units
VCCINTT
Threshold for the VCCINT supply
0.4
1.0
V
VCCAUXT
Threshold for the VCCAUX supply
0.8
2.0
V
VCCO2T
Threshold for the VCCO Bank 2 supply
0.4
1.0
V
Notes:
1.
VCCINT, VCCAUX, and VCCO supplies to the FPGA can be applied in any order. However, the FPGA’s configuration source (Platform Flash,
SPI Flash, parallel NOR Flash, microcontroller) might have specific requirements. Check the data sheet for the attached configuration
source. In Step 0 devices using the HSWAP internal pull-up, VCCINT must be applied before VCCAUX.
2.
To ensure successful power-on, VCCINT, VCCO Bank 2, and VCCAUX supplies must rise through their respective threshold-voltage ranges with
no dips at any point.
Table 75: Supply Voltage Ramp Rate
Symbol
Description
Min
Max
Units
VCCINTR
Ramp rate from GND to valid VCCINT supply level
0.2
50
ms
VCCAUXR
Ramp rate from GND to valid VCCAUX supply level
0.2
50
ms
VCCO2R
Ramp rate from GND to valid VCCO Bank 2 supply level
0.2
50
ms
Notes:
1.
VCCINT, VCCAUX, and VCCO supplies to the FPGA can be applied in any order. However, the FPGA’s configuration source (Platform Flash,
SPI Flash, parallel NOR Flash, microcontroller) might have specific requirements. Check the data sheet for the attached configuration
source. In Step 0 devices using the HSWAP internal pull-up, VCCINT must be applied before VCCAUX.
2.
To ensure successful power-on, VCCINT, VCCO Bank 2, and VCCAUX supplies must rise through their respective threshold-voltage ranges with
no dips at any point.
Table 76: Supply Voltage Levels Necessary for Preserving RAM Contents
Symbol
Description
Min
Units
VDRINT
VCCINT level required to retain RAM data
1.0
V
VDRAUX
VCCAUX level required to retain RAM data
2.0
V
Notes:
1.
RAM contents include configuration data.