TLV1571, TLV1578

2.7 V TO 5.5 V, 1-/8-CHANNEL, 10-BIT,

PARALLEL ANALOG-TO-DIGITAL CONVERTERS

SLAS170C –MARCH 1999 – REVISED FEBRUARY 2000

7

POST OFFICE BOX 655303

detailed description (continued)

configure the device

The device can be configured by writing to control registers CR0 and CR1.

Table 2. TLV1571/TLV1578 Programming Examples

REGISTER

INDEX

D7

D6

D5

D4

D3

D2

D1

D0

COMMENT

REGISTER

D9

D8

D7

D6

D5

D4

D3

D2

D1

D0

COMMENT

EXAMPLE1

CR0

0

0

0

0

0

0

0

0

0

0

Single channel

CR1

0

1

0

0

0

0

0

1

0

0

Single Input

EXAMPLE2

CR0

0

0

0

1

1

0

1

0

1

1

Sweep mode

CR1

0

1

0

0

0

0

1

1

0

0

2’s complement output

register read back

Control data written to the TLV1571/78 can be read back from the control registers CR0 and CR1. See Figure 2.

NOTE:

Data read out of CR1 reserved bits is don’t care.

power down

The TLV1571/TLV1578 offers two power-down modes, auto power down and software power down. This device

will automatically proceed to auto power-down mode if RD is not present one clock after conversion. Software

Table 3. Power Down Modes

PARAMETERS/MODES

AUTO POWER DOWN

SOFTWARE POWER DOWN

(CS = DVDD)

Maximum power down dissipation current

1 mA

10

µA

Comparator

Power down

Power down

Clock buffer

Power down

Power down

Reference

Active

Power down

Control registers

Saved

Saved

Minimum power down time

1 CLK

2 CLK

Minimum resume time

1 CLK

2 CLK

self-test modes

The TLV1571/TLV1578 provides three self test modes. These modes can be used to check whether the ADC

itself is working properly without having to supply an external signal. There are three tests that are controlled

by writing to CR1(D1,D0) (see Table 4).

Table 4. Self Tests

CR1(D1,D0)

SELF TEST VOLTAGE APPLIED

DIGITAL OUTPUT

0h

Normal, no self test applied

N/A

1h

VREFM applied to ADC input internally

000h

2h

(VREFP–VREFM)/2 applied to ADC input internally

200h

3h

VIN = VREFP applied to ADC input internally

3FFh