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AD5330/AD5331/AD5340/AD5341

Rev. A | Page 19 of 28

POWER-DOWN MODE

The AD5330/AD5331/AD5340/AD5341 have low power

consumption, dissipating only 0.35 mW with a 3 V supply and

0.7 mW with a 5 V supply. Power consumption can be further

reduced when the DAC is not in use by putting it into power-

down mode, which is selected by taking Pin PD low.

When the PD pin is high, the DAC works normally with a

typical power consumption of 140 μA at 5 V (115 μA at 3 V).

In power-down mode, however, the supply current falls to

200 nA at 5 V (80 nA at 3 V) when the DAC is powered down.

Not only does the supply current drop, but the output stage

is also internally switched from the output of the amplifier,

making it open-circuit. This has the advantage that the output

is three-state while the part is in power-down mode and provides

a defined input condition for whatever is connected to the

output of the DAC amplifier. The output stage is illustrated in

Figure 39

RESISTOR

STRING DAC

POWER-DOWN

CIRCUITRY

AMPLIFIER

VOUT

Figure 39. Output Stage During Power-Down

The bias generator, the output amplifier, the resistor string, and

all other associated linear circuitry are shut down when the

power-down mode is activated. However, the contents of the

registers are unaffected when in power-down. The time to exit

power-down is typically 2.5 μs for VDD = 5 V and 5 μs when

VDD = 3 V. This is the time from a rising edge on the PD pin to

when the output voltage deviates from its power-down voltage

(see

Figure 31

Table 9. AD5330/AD5331/AD5340 Truth Table1

CLR

LDAC

Function

No data transfer

Clear all registers

→1

Load input register

→1

Load input register and DAC register

Update DAC register

1 X = don’t care.

Table 10. AD5341 Truth Table1

CLR

LDAC

HBEN

Function

No data transfer

Clear all registers

→1

Load low byte input register

→1

Load high byte input register

→1

Load low byte input register and DAC register

→1

Load high byte input register and DAC register

Update DAC register

1 X = don’t care.

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