THS1206

SLAS217H – MAY 1999 – REVISED JULY 2003#

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7

Terminal Functions

TERMINAL

I/O

DESCRIPTION

NAME

NO.

I/O

DESCRIPTION

AINP

32

I

Analog input, single-ended or positive input of differential channel A

AINM

31

I

Analog input, single-ended or negative input of differential channel A

BINP

30

I

Analog input, single-ended or positive input of differential channel B

BINM

29

I

Analog input, single-ended or negative input of differential channel B

AVDD

23

I

Analog supply voltage

AGND

24

I

Analog ground

BVDD

7

I

Digital supply voltage for buffer

BGND

8

I

Digital ground for buffer

CONV_CLK

(CONVST)

15

I

Digital input. This input is used to apply an external conversion clock in continuous conversion mode. In single

conversion mode, this input functions as the conversion start (CONVST) input. A high to low transition on this

input holds simultaneously the selected analog input channels and initiates a single conversion of all selected

analog inputs.

CS0

22

I

Chip select input (active low)

CS1

21

I

Chip select input (active high)

DATA_AV

16

O

Data available signal, which can be used to generate an interrupt for processors and as a level information of

the internal FIFO. This signal can be configured to be active low or high and can be configured as a static level or

pulse output. See Table 14.

DGND

17

I

Digital ground. Ground reference for digital circuitry.

DVDD

18

I

Digital supply voltage

D0 – D9

1–6,

9–12

I/O/Z

Digital input, output; D0 = LSB

D10/RA0

13

I/O/Z

Digital input, output. The data line D10 is also used as an address line (RA0) for the control register. This is

required for writing to the control register 0 and control register 1. See Table 8.

D11/RA1

14

I/O/Z

Digital input, output (D11 = MSB). The data line D11 is also used as an address line (RA1) for the control

register. This is required for writing to control register 0 and control register 1. See Table 8.

REFIN

28

I

Common-mode reference input for the analog input channels. It is recommended that this pin be connected to

the reference output REFOUT.

REFP

26

I

Reference input, requires a bypass capacitor of 10

µF to AGND in order to bypass the internal reference

voltage. An external reference voltage at this input can be applied. This option can be programmed through

control register 0. See Table 9.

REFM

25

I

Reference input, requires a bypass capacitor of 10

µF to AGND in order to bypass the internal reference

voltage. An external reference voltage at this input can be applied. This option can be programmed through

control register 0. See Table 9.

REFOUT

27

O

Analog fixed reference output voltage of 2.5 V. Sink and source capability of 250

µA. The reference output

requires a capacitor of 10

µF to AGND for filtering and stability.

RD(1)

19

I

The RD input is used only if the WR input is configured as a write only input. In this case, it is a digital input, active

low as a data read select from the processor. See timing section.

WR (R/W)(1)

20

I

This input is programmable. It functions as a read-write input R/W and can also be configured as a write-only

input WR, which is active low and used as data write select from the processor. In this case, the RD input is used

as a read input from the processor. See timing section.

(1) The start-conditions of RD and WR (R/W) are unknown. The first access to the ADC has to be a write access to initialize the ADC.