To accommodate the diverse voltage supply requirements of processors, ASICs, and complex FPGAs, system board voltages are moving from being mostly either 5.0 V and/or 3.3 V to being a mixture of several voltages, including 1.8 V, 2.5 V, 3.3 V, 5.0 V, and 1.0 V and lower.
Figure 1 shows the expected core voltage trends for ASICs and complex FPGAs. Although the exact percentages are uncertain, system boards are clearly moving away from using only a 5.0 V and/or 3.3 V supply voltage towards the use of different on-board components that have different core voltages.
Figure 1: Use of Multiple Voltages on One Board
MAX 7000B Devices Can Interface with Multiple I/O Voltages
Product-term-based PLDs interface with a variety of processors, ASICs, memory devices, and complex FPGAs that are present on a system board. As these components offer more diverse core voltages, product-term-based PLDs must provide the capability to interface with their multiple voltage levels.
As shown in Table 1, MAX® 7000B devices can interface with 1.8 V, 2.5 V, and 3.3 V, depending on the VCCIO setting.| Table 1. MAX 7000B Voltage Interfaces | ||||||
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VCCIO set at
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Input Voltage
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Output Voltage
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1.8 V
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2.5 V
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3.3 V
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1.8 V
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2.5 V
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3.3 V
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| 1.8 V |
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| 2.5 V |
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| 3.3 V |
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Most product-term-based PLDs can only support one voltage level at any given time. However, MAX 7000B devices feature I/Os that are split into two I/O banks, each with its own VCCIO setting. With the VCCIO set at the appropriate level, I/Os within each bank can be configured to support a voltage level independent of I/Os in the other bank. For example, a MAX 7000B device can interface with a 1.8-V processor in one I/O bank while providing the decoded address for a 3.3-V memory component on the other.
Figure 2: MAX 7000B Device's Split I/O Bank Architecture
MAX 7000B devices are the only product-term-based PLDs that can support multiple voltage levels simultaneously. Using a MAX 7000B device on a system board eliminates the need of voltage translators and allows the board to interface with lower voltage levels, including 1.8 V.
Today's technology requires multiple voltage levels on one system board. MAX 7000B devices meet this need by offering the capability to interface with multiple voltage levels on the same board.
