Texas Instruments THS1206CDA, THS1206QDAR, THS1206QDA, THS1206IDAR, THS1206IDA Datasheet

THS1206 12-BIT 6 MSPS, SIMULTANEOUS SAMPLING ANALOG-TO-DIGITAL CONVERTERS

SLAS217D ± MAY 1999 ± REVISED APRIL 2000

features

applications

D High-Speed 6 MSPS ADC

D

Radar Applications

D 4 Single-Ended or 2 Differential Inputs

D

Communications

D Simultaneous Sampling of 4 Single-Ended

D

Control Applications

Signals or 2 Differential Signals or

D High-Speed DSP Front-End

Combination of Both

D

Automotive Applications

D Differential Nonlinearity Error: ±1 LSB

D Integral Nonlinearity Error: ±1.5 LSB

DA PACKAGE

D Signal-to-Noise and Distortion Ratio: 68 dB

(TOP VIEW)

at fI = 2 MHz

D0

AINP

1

32

D Auto-Scan Mode for 2, 3, or 4 Inputs

D1

2

31

AINM

D 3-V or 5-V Digital Interface Compatible

D2

3

30

BINP

D Low Power: 216 mW Max

D3

4

29

BINM

D 5-V Analog Single Supply Operation

D4

5

28

REFIN

D5

REFOUT

D

Internal Voltage References . . . 50 PPM/°C

6

27

BVDD

7

26

REFP

and ±5% Accuracy

REFM

D

Glueless DSP Interface

BGND

8

25

D6

9

24

AGND

Parallel C/DSP Interface

D

D7

10

23

AVDD

Integrated FIFO

D

D8

11

22

CS0

D Available in TSSOP Package

D9

12

21

CS1

D10/RA0

13

20

WR

(R/W)

description

D11/RA1

14

19

RD

CONV_CLK

DVDD

The THS1206 is a CMOS, low-power, 12-bit,

(CONVST)

15

18

DATA_AV

16

17

DGND

6 MSPS analog-to-digital converter (ADC). The

speed, resolution, bandwidth, and single-supply

operation are suited for applications in radar,

imaging, high-speed acquisition, and communications. A multistage pipelined architecture with output error

correction logic provides for no missing codes over the full operating temperature range. Internal control

registers are used to program the ADC into the desired mode. The THS1206 consists of four analog inputs,

which are sampled simultaneously. These inputs can be selected individually and configured to single-ended

or differential inputs. An integrated 16 word deep FIFO allows the storage of data in order to take the load off

of the processor connected to the ADC. Internal reference voltages for the ADC (1.5 V and 3.5 V) are provided.

An external reference can also be chosen to suit the dc accuracy and temperature drift requirements of the application. Two different conversion modes can be selected. In single conversion mode, a single and simultaneous conversion of up to four inputs can be initiated by using the single conversion start signal (CONVST). The conversion clock in single conversion mode is generated internally using a clock oscillator circuit. In continuous conversion mode, an external clock signal is applied to the CONV_CLK input of the THS1206. The internal clock oscillator is switched off in continuous conversion mode.

The THS1206C is characterized for operation from 0°C to 70°C, the THS1206I is characterized for operation from ±40°C to 85°C, the THS1206Q is characterized to meet the rigorous requirements of the automotive environment from ±40°C to 125°C, and the THS1206M is characterized for operation over the full military temperature range of ±55°C to 125°C.

Please be aware that an important notice concerning availability, standard warranty, and use in critical applications of Texas Instruments semiconductor products and disclaimers thereto appears at the end of this data sheet.

PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of Texas Instruments standard warranty. Production processing does not necessarily include testing of all parameters.

Copyright 2000, Texas Instruments Incorporated

On products compliant to MIL-PRF-38535, all parameters are tested unless otherwise noted. On all other products, production processing does not necessarily include testing of all parameters.

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1

THS1206
12-BIT 6 MSPS, SIMULTANEOUS SAMPLING
ANALOG-TO-DIGITAL CONVERTERS
SLAS217D ± MAY 1999 ± REVISED APRIL 2000
		AVAILABLE OPTIONS
				PACKAGED DEVICE
		TA			TSSOP
					(DA)
		0°C to 70°C		THS1206CDA
		±40°C to 85°C		THS1206IDA
		±40°C to 125°C		THS1206QDA
		±55°C to 125°C		THS1206MDA
functional block diagram
				AVDD				DVDD
REFP					3.5 V					2.5 V
									1.225 V
										REFOUT
					1.5 V				REF
REFM
REFIN
AINP	S/H				VREFM					DATA_AV
				VREFP
AINM	S/H	Single	+							BVDD
				12 Bit
		Ended			12		FIFO		12	D0
		and/or		Pipeline
			±			16		× 12		D1
		Differential		ADC
BINP	S/H									D2
		MUX
									Buffers	D3
										D4
										D5
BINM	S/H									D6
										D7
										D8
										D9
CONV_CLK (CONVST)										D10/RA0
CS0	Logic									D11/RA1
CS1	and			Control						BGND
RD	Control
				Register
WR (R/W)
						AGND			DGND

2	POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

THS1206

12-BIT 6 MSPS, SIMULTANEOUS SAMPLING

ANALOG-TO-DIGITAL CONVERTERS

SLAS217D ± MAY 1999 ± REVISED APRIL 2000

Terminal Functions

TERMINAL

I/O

DESCRIPTION

NAME

NO.

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

15

I

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

(CONVST)

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.

22

I

Chip select input (active low)

CS0

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 F 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 F 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 A. The

reference output requires a capacitor of 10 F to AGND for filtering and stability.

²

19

I

The

input is used only if the

input is configured as a write only input. In this case, it is a

RD

RD

WR

digital input, active low as a data read select from the processor. See timing section.

²

20

I

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

WR

(R/W)

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.

² 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.

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3

THS1206

12-BIT 6 MSPS, SIMULTANEOUS SAMPLING ANALOG-TO-DIGITAL CONVERTERS

SLAS217D ± MAY 1999 ± REVISED APRIL 2000

absolute maximum ratings over operating free-air temperature (unless otherwise noted)²

Supply voltage range, DGND to DVDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . . . ±0.3 V to 6.5 V
BGND to BVDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . . ±0.3 V to 6.5 V
AGND to AVDD . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . . ±0.3 V to 6.5 V
Analog input voltage range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	AGND ± 0.3 V to AVDD + 1.5 V
Reference input voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	±0.3 + AGND to AVDD + 0.3 V
Digital input voltage range . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	±0.3 V to BVDD/DVDD + 0.3 V
Operating virtual junction temperature range, TJ . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . ±55°C to 150°C
Operating free-air temperature range,TA THS1206C . . . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . . . . 0°C to 70°C
THS1206I . . . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . . ±40°C to 85°C
THS1206Q . . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . ±40°C to 125°C
THS1206M . . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . ±55°C to 125°C
Storage temperature range, Tstg . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .	. . . . . . . . . . . . . ±65°C to 150°C
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds . . . . . . . . . .	. . . . . . . . . . . . . . . . . . . . . 260°C

²Stresses beyond those listed under ªabsolute maximum ratingsº may cause permanent damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated under ªrecommended operating conditionsº is not implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.

DISSIPATION RATING TABLE

	PACKAGE	TA ≤ 25°C	DERATING FACTOR	TA = 70°C	TA = 85°C	TA = 125°C
		POWER RATING	ABOVE T = 25°C³	POWER RATING	POWER RATING	POWER RATING
			A
	DA	1453 mW	11.62 mW/°C	930 mW	756 mW	291 mW

³This is the inverse of the traditional junction-to-ambient thermal resistance (RθJA). Thermal resistances are not production tested and are for informational purposes only.

recommended operating conditions power supply

		MIN	NOM	MAX	UNIT
	AVDD	4.75	5	5.25
Supply voltage	DVDD	3	3.3	5.25	V
	BVDD	3	3.3	5.25

analog and reference inputs

	MIN	NOM	MAX	UNIT
Analog input voltage in single-ended configuration	VREFM		VREFP	V
Common-mode input voltage VCM in differential configuration	1	2.5	4	V
External reference voltage,VREFP (optional)		3.5	AVDD±1.2	V
External reference voltage, VREFM (optional)	1.4	1.5		V
Input voltage difference, REFP ± REFM		2		V

4	POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

THS1206 12-BIT 6 MSPS, SIMULTANEOUS SAMPLING ANALOG-TO-DIGITAL CONVERTERS

SLAS217D ± MAY 1999 ± REVISED APRIL 2000

recommended operating conditions (continued) digital inputs

		MIN	NOM	MAX	UNIT
High-level input voltage, VIH	BVDD = 3.3 V	2			V
	BVDD = 5.25 V	2.6			V
Low-level input voltage, VIL	BVDD = 3.3 V			0.6	V
	BVDD = 5.25 V			0.6	V
Input CONV_CLK frequency	DVDD = 3 V to 5.25 V	0.1		6	MHz
CONV_CLK pulse duration, clock high, tw(CONV_CLKH)	DVDD = 3 V to 5.25 V	80	83	5000	ns
CONV_CLK pulse duration, clock low, tw(CONV_CLKL)	DVDD = 3 V to 5.25 V	80	83	5000	ns
	THS1206CDA	0		70
Operating free-air temperature, TA	THS1206IDA	±40		85	°C
	THS1206QDA	±40		125
	THS1206MDA	±55		125

electrical characteristics over recommended operating conditions, VREF = internal (unless otherwise noted)

digital specifications

	PARAMETER	TEST CONDITIONS			MIN	TYP MAX	UNIT
Digital inputs
IIH	High-level input current	DVDD = digital inputs			±50	50	A
IIL	Low-level input current	Digital input = 0 V			±50	50	A
Ci	Input capacitance					5	pF
Digital outputs
VOH	High-level output voltage				BVDD±0.5		V
			BV	= 3.3 V,	BVDD±0.5
		IOH = ±50 A	DD
VOL	Low-level output voltage		BVDD	= 5 V		0.4	V
						0.4
IOZ	High-impedance-state output current	CS1 = DGND, CS0 = DVDD			±10	10	A
CO	Output capacitance					5	pF
CL	Load capacitance at databus D0 ± D11					30	pF

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5

THS1206

12-BIT 6 MSPS, SIMULTANEOUS SAMPLING ANALOG-TO-DIGITAL CONVERTERS

SLAS217D ± MAY 1999 ± REVISED APRIL 2000

electrical characteristics over recommended operating conditions, VREF = internal (unless otherwise noted) (continued)

dc specifications

	PARAMETER	TEST CONDITIONS			MIN	TYP	MAX	UNIT
	Resolution				12			Bits
Accuracy
	Integral nonlinearity, INL	C and I suffix					±1.5	LSB
		Q and M suffix					±1.8
	Differential nonlinearity, DNL						±1	LSB
	Offset error	After calibration in single-ended mode			±15²		15²	mV
		After calibration in differential mode			±5²		5²	mV
	Gain error						1%	FSR
Analog input
	Input capacitance					15		pF
	Input leakage current	VAIN = VREFM to VREFP					±10	A
Internal voltage reference
	Accuracy, VREFP	C and I suffix			3.33	3.5	3.67	V
		Q and M suffix			3.3	3.5	3.7
	Accuracy, VREFM	C and I suffix			1.42	1.5	1.58	V
		Q and M suffix			1.3	1.5	1.7
	Temperature coefficient					50		PPM/°C
	Reference noise					100		V
	Accuracy, REFOUT	C and I suffix			2.475	2.5	2.525	V
		Q and M suffix			2.3	2.5	2.7
Power supply
IDDA	Analog supply current	AVDD =5 V, BVDD = DVDD = 3.3 V				36	40	mA
IDDD	Digital supply voltage	AVDD = 5 V, BVDD = DVDD = 3.3 V				0.5	1	mA
IDDB	Buffer supply voltage	AVDD = 5 V, BVDD = DVDD = 3.3 V				1.5	4	mA
IDD_P	Supply current in power-down mode	AVDD = 5 V,		C and I suffix			7	mA
		BVDD = DVDD = 3.3 V		Q and M suffix			10
	Power dissipation	AVDD = 5 V, DVDD = BVDD = 3.3 V				186	216	mW
	Power dissipation in power down	AVDD = 5 V, DVDD = BVDD = 3.3 V				30		mW

² Not production tested for M and Q suffix devices.

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THS1206 12-BIT 6 MSPS, SIMULTANEOUS SAMPLING ANALOG-TO-DIGITAL CONVERTERS

SLAS217D ± MAY 1999 ± REVISED APRIL 2000

electrical characteristics over recommended operating conditions, VREF = internal, fs = 6 MHz, fI = 2 MHz at ±1dBFS (unless otherwise noted) (continued)

ac specifications, AVDD = 5 V, BVDD = DVDD = 3.3 V, CL < 30 pF

	PARAMETER	TEST CONDITIONS		MIN	TYP	MAX	UNIT
SINAD	Signal-to-noise ratio + distortion	Differential mode		63	68		dB
		Single-ended mode (see Note 1)			64		dB
SNR	Signal-to-noise ratio	Differential mode		64	69		dB
		Single-ended mode (see Note 1)			65		dB
		Differential mode	C and I suffix		±73	±69
THD	Total harmonic distortion		Q and M suffix		±73	±67	dB
		Single-ended mode	C and I suffix		±73	±69
			Q and M suffix		±73	±67
ENOB	Effective number of bits	Differential mode		10.3	11		Bits
(SNR)		Single-ended mode (see Note 1)			10.4		Bits
SFDR Spurious free dynamic range		Differential mode		68	75		dB
		Single-ended mode		68	75		dB
Analog Input
	Full-power bandwidth with a source impedance of	FS sinewave, ±3 dB			96		MHz
	150 Ω in differential configuration.
	Full-power bandwidth with a source impedance of	FS sinewave, ±3 dB			54		MHz
	150 Ω in single-ended configuration.
	Small-signal bandwidth with a source impedance	100 mVpp sinewave, ±3 dB			96		MHz
	of 150 Ω in differential configuration.
	Small-signal bandwidth with a source impedance	100 mVpp sinewave, ±3 dB			54		MHz
	of 150 Ω in single-ended configuration.

NOTE 1: The SNR (ENOB) and SINAD is degraded typically by 2 dB in single-ended mode when the reading of data is asynchronous to the sampling clock.

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7

THS1206

12-BIT 6 MSPS, SIMULTANEOUS SAMPLING ANALOG-TO-DIGITAL CONVERTERS

SLAS217D ± MAY 1999 ± REVISED APRIL 2000

timing specifications, AVDD = 5 V, BVDD = DVDD = 3.3 V, VREF = internal, CL < 30 pF

	PARAMETER	TEST CONDITIONS	MIN TYP MAX	UNIT
td(DATA_AV)	Delay time		5	ns
td(o)	Delay time		5	ns
tpipe	Latency		5	CONV
				CLK

timing specification of the single conversion mode²

	PARAMETER			TEST CONDITIONS		MIN	TYP	MAX	UNIT
tc	Clock cycle of the internal clock oscillator					159	167	175	ns
tw1	Pulse width,					1.5×tc			ns
		CONVST
tdA	Aperture time						1		ns
				1 analog input		2×tc			ns
t2	Time between consecutive start of single conversion			2 analog inputs		3×tc
				3 analog inputs		4×tc			ns
				4 analog inputs		5×tc
				1 analog input,	TL = 1			6×tc	ns
	Delay time, DATA_AV becomes active for the trigger			2 analog inputs, TL = 2				7×tc
	level condition: TRIG0 = 0, TRIG1 = 0			3 analog inputs, TL = 3				8×tc	ns
				4 analog inputs,	TL = 4			9×tc
				1 analog input,	TL = 4			3×t2 +6×tc	ns
td(DATA_AV)	Delay time, DATA_AV becomes active for the trigger			2 analog inputs,	TL = 4			t2 +7×tc
	level condition: TRIG0 = 1, TRIG1 = 0			3 analog inputs,	TL = 6			t2 +8×tc	ns
				4 analog inputs,	TL = 8			t2 +9×tc
				1 analog input,	TL = 8			7×t2 +6×tc	ns
	Delay time, DATA_AV becomes active for the trigger			2 analog inputs, TL = 8				3×t2 +7×tc
	level condition: TRIG0 = 0, TRIG1 = 1			3 analog inputs, TL = 9				2×t2 +8×tc	ns
				4 analog inputs,	TL = 12			2×t2 +9×tc
	Delay time, DATA_AV becomes active for the trigger			1 analog input,	TL = 14			13×t2 +6×tc	ns
td(DATA_AV)				2 analog inputs, TL = 12				5×t2 +7×tc
	level condition: TRIG0 = 1, TRIG1 = 1
				3 analog inputs, TL = 12				3×t2 +8×tc	ns

² Timing parameters are ensured by design but are not tested.

8	POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

THS1206 12-BIT 6 MSPS, SIMULTANEOUS SAMPLING ANALOG-TO-DIGITAL CONVERTERS

SLAS217D ± MAY 1999 ± REVISED APRIL 2000

detailed description

reference voltage

The THS1206 has a built-in reference, which provides the reference voltages for the ADC. VREFP is set to 3.5 V and VREFM is set to 1.5 V. An external reference can also be used through two reference input pins, REFP and REFM, if the reference source is programmed as external. The voltage levels applied to these pins establish the upper and lower limits of the analog inputs to produce a full-scale and zero-scale reading respectively.

analog inputs

The THS1206 consists of 4 analog inputs, which are sampled simultaneously. These inputs can be selected individually and configured as single-ended or differential inputs. The desired analog input channel can be programmed.

converter

The THS1206 uses a 12-bit pipelined multistaged architecture with 4 1-bit stages followed by 4 2-bit stages, which achieves a high sample rate with low power consumption. The THS1206 distributes the conversion over several smaller ADC sub-blocks, refining the conversion with progressively higher accuracy as the device passes the results from stage to stage. This distributed conversion requires a small fraction of the number of comparators used in a traditional flash ADC. A sample-and-hold amplifier (SHA) within each of the stages permits the first stage to operate on a new input sample while the second through the eighth stages operate on the seven preceding samples.

conversion modes

The conversion can be performed in two different conversion modes. In the single conversion mode, the conversion is initiated by an external signal (CONVST). An internal oscillator controls the conversion time. In the continuous conversion mode, an external clock signal is applied to the clock input (CONV_CLK). A new conversion is started with every falling edge of the applied clock signal.

sampling rate

The maximum possible conversion rate per channel is dependent on the selected analog input channels. Table 1 shows the maximum conversion rate in the continuous conversion mode for different combinations.

Table 1. Maximum Conversion Rate in Continuous Conversion Mode

	CHANNEL CONFIGURATION	NUMBER OF	MAXIMUM CONVERSION
		CHANNELS	RATE PER CHANNEL
	1 single-ended channel	1	6 MSPS
	2 single-ended channels	2	3 MSPS
	3 single-ended channels	3	2 MSPS
	4 single-ended channels	4	1.5 MSPS
	1 differential channel	1	6 MSPS
	2 differential channels	2	3 MSPS
	1 single-ended and 1 differential channel	2	3 MSPS
	2 single-ended and 1 differential channels	3	2 MSPS

The maximum conversion rate in the continuous conversion mode per channel, fc, is given by:

fc + #6channelsMSPS

Table 2 shows the maximum conversion rate in the single conversion mode.

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9

THS1206

12-BIT 6 MSPS, SIMULTANEOUS SAMPLING ANALOG-TO-DIGITAL CONVERTERS

SLAS217D ± MAY 1999 ± REVISED APRIL 2000

sampling rate (continued)

Table 2. Maximum Conversion Rate in Single Conversion Mode

	CHANNEL CONFIGURATION	NUMBER OF	MAXIMUM CONVERSION
		CHANNELS	RATE PER CHANNEL
	1 single-ended channel	1	3 MSPS
	2 single-ended channels	2	2 MSPS
	3 single-ended channels	3	1.5 MSPS
	4 single-ended channels	4	1.2 MSPS
	1 differential channel	1	3 MSPS
	2 differential channels	2	2 MSPS
	1 single-ended and 1 differential channel	2	1.5 MSPS
	2 single-ended and 1 differential channels	3	1.2 MSPS

single conversion mode

In single conversion mode, a single conversion of the selected analog input channels is performed. The single conversion mode is selected by setting bit 1 of control register 0 to 1.

A single conversion is initiated by pulsing the CONVST input. On the falling edge of CONVST, the sample and hold stages of the selected analog inputs are placed into hold simultaneously, and the conversion sequence for the selected channels is started.

The conversion clock in single conversion mode is generated internally using a clock oscillator circuit. The signal DATA_AV (data available) becomes active when the trigger level is reached and indicates that the converted sample(s) is (are) written into the FIFO and can be read out. The trigger level in the single conversion mode can be selected according to Table 13.

Figure 1 shows the timing of the single conversion mode. In this mode, up to four analog input channels can be selected to be sampled simultaneously (see Table 2).

t2

CONVST

t1

t1

td(A)

AIN

Sample N

tDATA_AV

DATA_AV,

Trigger Level = 1

Figure 1. Timing of Single Conversion Mode

The time (t2) between consecutive starts of single conversions is dependent on the number of selected analog

input channels. The time tDATA_AV, until DATA_AV becomes active is given by: tDATA_AV = tpipe + n ×tc. This equation is valid for a trigger level which is equivalent to the number of selected analog input channels. For all

other trigger level conditions refer to the timing specifications of single conversion mode.

10	POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

THS1206 12-BIT 6 MSPS, SIMULTANEOUS SAMPLING ANALOG-TO-DIGITAL CONVERTERS

SLAS217D ± MAY 1999 ± REVISED APRIL 2000

continuous conversion mode

The internal clock oscillator used in the single-conversion mode is switched off in continuous conversion mode. In continuous conversion mode, (bit 1 of control register 0 set to 0) the ADC operates with a free running external clock signal CONV_CLK. With every rising edge of the CONV_CLK signal a new converted value is written into the FIFO.

Figure 2 shows the timing of continuous conversion mode when one analog input channel is selected. The maximum throughput rate is 6 MSPS in this mode. The timing of the DATA_AV signal is shown here in the case of a trigger level set to 1 or 4.

Sample N	Sample N+1	Sample N+2	Sample N+3	Sample N+4	Sample N+5	Sample N+6	Sample N+7	Sample N+8
Channel 1	Channel 1	Channel 1	Channel 1	Channel 1	Channel 1	Channel 1	Channel 1	Channel 1

AIN
	td(A)	td(pipe)
tw(CONV_CLKH)		tw(CONV_CLKL)
50%	50%
CONV_CLK
	tc				td(O)
Data Into	Data N±5	Data N±4	Data N±3	Data N±2	Data N±1	Data N	Data N+1	Data N+2	Data N+3
FIFO	Channel 1	Channel 1	Channel 1	Channel 1	Channel 1	Channel 1	Channel 1	Channel 1	Channel 1

td(DATA_AV)

DATA_AV,

Trigger Level = 1

td(DATA_AV)

DATA_AV,

Trigger Level = 4

Figure 2. Timing of Continuous Conversion Mode (1-channel operation)

Figure 3 shows the timing of continuous conversion mode when two analog input channels are selected. The maximum throughput rate per channel is 3 MSPS in this mode. The data flow in the bottom of the figure shows the order the converted data is written into the FIFO. The timing of the DATA_AV signal shown here is for a trigger level set to 2 or 4.

Sample N		Sample N+1		Sample N+2		Sample N+3		Sample N+4
Channel 1,2		Channel 1,2		Channel 1,2		Channel 1,2		Channel 1,2
AIN
	td(A)	td(Pipe)
tw(CONV_CLKH)		tw(CONV_CLKL)
50%	50%
CONV_CLK
	tc				td(O)
Data Into	Data N±3	Data N±2	Data N±2	Data N±1	Data N±1	Data N	Data N	Data N+1	Data N+1
FIFO	Channel 2	Channel 1	Channel 2	Channel 1	Channel 1	Channel 1	Channel 2	Channel 1	Channel 2

td(DATA_AV)

DATA_AV,

Trigger Level = 2

td(DATA_AV)

DATA_AV,

Trigger Level = 4

Figure 3. Timing of Continuous Conversion Mode (2-channel operation)

POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

11

THS1206

12-BIT 6 MSPS, SIMULTANEOUS SAMPLING ANALOG-TO-DIGITAL CONVERTERS

SLAS217D ± MAY 1999 ± REVISED APRIL 2000

continuous conversion mode (continued)

Figure 4 shows the timing of continuous conversion mode when three analog input channels are selected. The maximum throughput rate per channel is 2 MSPS in this mode. The data flow in the bottom of the figure shows in which order the converted data is written into the FIFO. The timing of the DATA_AV signal shown here is for a trigger level set to 3.

Sample N	Sample N+1	Sample N+2
Channel 1,2,3	Channel 1,2,3	Channel 1,2,3

AIN
	td(A)	td(Pipe)
tw(CONV_CLKH)		tw(CONV_CLKL)
50%	50%
CONV_CLK
	tc				td(O)
Data Into	Data N±2	Data N±2	Data N±1	Data N±1	Data N±1	Data N	Data N	Data N+1
FIFO	Channel 2	Channel 3	Channel 2	Channel 2	Channel 3	Channel 1	Channel 2	Channel 3

td(DATA_AV)

DATA_AV,

Trigger Level = 3

Figure 4. Timing of Continuous Conversion Mode (3-channel operation)

Figure 5 shows the timing of continuous conversion mode when four analog input channels are selected. The maximum throughput rate per channel is 1.5 MSPS in this mode. The data flow in the bottom of the figure shows in which order the converted data is written into the FIFO. The timing of the DATA_AV signal shown here is for a trigger level of 4.

Sample N	Sample N+1	Sample N+2
Channel 1,2,3,4	Channel 1,2,3,4	Channel 1,2,3,4

AIN
	td(A)	td(Pipe)
tw(CONV_CLKH)
		tw(CONV_CLKL)
50%	50%
CONV_CLK
	tc				td(O)
Data Into	Data N±2	Data N±1	Data N±1	Data N±1	Data N±1	Data N	Data N	Data N	Data N
FIFO	Channel 4	Channel 1	Channel 2	Channel 3	Channel 4	Channel 1	Channel 2	Channel 3	Channel 4

td(DATA_AV)

DATA_AV,

Trigger Level = 4

Figure 5. Timing of Continuous Conversion Mode (4-channel operation)

12	POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

THS1206 12-BIT 6 MSPS, SIMULTANEOUS SAMPLING ANALOG-TO-DIGITAL CONVERTERS

SLAS217D ± MAY 1999 ± REVISED APRIL 2000

digital output data format

The digital output data format of the THS1206 can either be in binary format or in twos complement format. The following tables list the digital outputs for the analog input voltages.

Table 3. Binary Output Format for Single-Ended Configuration

SINGLE-ENDED, BINARY OUTPUT

ANALOG INPUT VOLTAGE	DIGITAL OUTPUT CODE
AIN = VREFP	FFFh
AIN = (VREFP + VREFM)/2	800h
AIN = VREFM	000h

Table 4. Two's Complement Output Format for Single-Ended Configuration

SINGLE-ENDED, TWOS COMPLEMENT

ANALOG INPUT VOLTAGE	DIGITAL OUTPUT CODE
AIN = VREFP	7FFh
AIN = (VREFP + VREFM)/2	000h
AIN = VREFM	800h

Table 5. Binary Output Format for Differential Configuration

DIFFERENTIAL, BINARY OUTPUT

ANALOG INPUT VOLTAGE	DIGITAL OUTPUT CODE
Vin = AINP ± AINM
VREF = VREFP ± VREFM
Vin = VREF	FFFh
Vin = 0	800h
Vin = ±VREF	000h

Table 6. Two's Complement Output Format for Differential Configuration

DIFFERENTIAL, BINARY OUTPUT

ANALOG INPUT VOLTAGE	DIGITAL OUTPUT CODE
Vin = AINP ± AINM
VREF = VREFP ± VREFM
Vin = VREF	7FFh
Vin = 0	000h
Vin = ±VREF	800h

POST OFFICE BOX 655303 •DALLAS, TEXAS 75265

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