Power-Down And Sleep Modes - Analog Devices AD9776 Instruction Manual

AD9776/AD9778/AD9779
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ALL INTERPOLATION MODES
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Figure 81. Digital 3.3 V Supply, I Data Only, Real Mode, Includes Modulation
Modes and Zero Stuffing
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DAC
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Figure 82. Power Dissipation, Digital 1.8 V Supply, I and Q Data, Dual DAC
Mode, Does Not Include Zero Stuffing
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DAC
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Figure 83. Power Dissipation, Clock 1.8 V Supply, I and Q Data, Dual DAC
Mode, Does Not Include Zero Stuffing
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(MSPS)
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/8,
/4,
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NO MODULATION
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(MSPS)
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NO MODULATION
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ALL INTERPOLATION MODES
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Figure 84. Digital 3.3 V Supply, I and Q Data, Dual DAC Mode
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Figure 85. Power Dissipation of Inverse Sinc Filter

POWER-DOWN AND SLEEP MODES

The AD977x has a variety of power-down modes, so that the
digital engine, main TxDACs, or auxiliary DACs can be
powered down individually or together. Via the SPI port, the
main TxDACs can be placed in sleep or power-down mode. In
sleep mode, the TxDAC output is turned off, thus reducing
power dissipation. The reference remains powered on, however,
so that recovery from sleep mode is very fast. With the power-
down mode bit set (Reg. 0x00, Bit 4), all analog and digital
circuitry, including the reference, is powered down. The SPI
port remains active in this mode. This mode offers more
substantial power savings than sleep mode, but the turn on
time is much longer. The auxiliary DACs also have the
capability to be programmed into sleep mode via the SPI port.
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DAC
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