Datasheet

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POWER-DOWN MODES

Global Power Down

Standby

Output Buffer Disable

Input Clock Stop

Power Supply Sequence

ADS6145, ADS6144

ADS6143, ADS6142

SLWS198B – JULY 2007 – REVISED MARCH 2008

The ADS614X have four power-down modes – global power down, standby, output buffer disable, and input

clock stopped. These modes can be set using the serial interface or using the parallel interface (pins SDATA and

PDN).

Table 14. Power-Down Modes

POWER-DOWN PARALLEL INTERFACE SERIAL INTERFACE

TOTAL POWER, WAKE-UP TIME

MODES REGISTER BIT

mW (to valid data)

SDATA PDN

(Table 5 )

Normal operation Low Low <PDN OBUF>=0 and 417

<STBY>=0

Standby Low High <PDN OBUF>=0 and 72 Slow (15 µ s)

<STBY>=1

Output buffer disable High Low <PDN OBUF>=1 and 408 Fast (200 ns)

<STBY>=0

Global power down High High <PDN OBUF>=1 and 30 Slow (15 µ s)

<STBY>=1

In this mode, the A/D converter, internal references, and the output buffers are powered down and the total

power dissipation reduces to about 30 mW. The output buffers are in a high-impedance state. The wake-up time

from the global power down to output data becoming valid in normal mode is a maximum of 50 µ s. Note that

after coming out of global power down, optimum performance is achieved after the internal reference voltages

have stabilized (about 1 ms).

Only the A/D converter is powered down and total power dissipation is approximately 72 mW. The wake-up time

from standby to output data becoming valid is a maximum of 50 µ s.

The data output buffers can be disabled, reducing total power to about 408 mW. With the buffers disabled, the

outputs are in a high-impedance state. The wake-up time from this mode to data becoming valid in normal mode

is a maximum of 500 ns in LVDS mode and 200 ns in CMOS mode.

The converter enters this mode when the input clock frequency falls below 1 MSPS. Power dissipation is

approximately 120 mW, and the wake-up time from this mode to data becoming valid in normal mode is a

maximum of 50 µ s.

During power-up, the AVDD and DRVDD supplies can come up in any sequence. The two supplies are

separated inside the device. Externally, they can be driven from separate supplies or from a single supply.

Product Folder Link(s): ADS6145, ADS6144 ADS6143, ADS6142