THS10082IDARG4 [TI]
IC,DATA ACQ SYSTEM,2-CHANNEL,10-BIT,TSSOP,32PIN,PLASTIC;型号: | THS10082IDARG4 |
厂家: | TEXAS INSTRUMENTS |
描述: | IC,DATA ACQ SYSTEM,2-CHANNEL,10-BIT,TSSOP,32PIN,PLASTIC 光电二极管 |
文件: | 总35页 (文件大小:219K) |
中文: | 中文翻译 | 下载: | 下载PDF数据表文档文件 |
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
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of the processor connected to the ADC. Internal
reference voltages for the ADC (1.5 V and 3.5 V) are
provided.
FEATURES
D
Simultaneous Sampling of Two Single-Ended
Signals or One Differential Signal
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 the single conversion mode, a single and
simultaneous conversion can be initiated by using the
single conversion start signal (CONVST). The conversion
clock in the single conversion mode is generated internally
using a clock oscillator circuit. In the continuous
conversion mode, an external clock signal is applied to the
CONV_CLK input of the THS10082. The internal clock
oscillator is switched off in the continuous conversion
mode.
D
Integrated 16-Word FIFO
D
Signal-to-Noise and Distortion Ratio: 59 dB at
f = 2 MHz
I
D
D
D
D
D
D
D
Differential Nonlinearity Error: ±1 LSB
Integral Nonlinearity Error: ±1 LSB
Auto-Scan Mode for Two Inputs
3-V or 5-V Digital Interface Compatible
Low Power: 216 mW Max
5-V Analog Single Supply Operation
Internal Voltage References . . . 50 PPM/°C
and ±5% Accuracy
The THS10082C is characterized for operation from 0°C
to 70°C, and the THS10082I is characterized for operation
from –40°C to 85°C.
D
Parallel µC/DSP Interface
APPLICATIONS
DA PACKAGE
(TOP VIEW)
D
D
D
D
D
Radar Applications
Communications
D0
D1
D2
D3
D4
D5
OV_FL
RESET
AINP
1
32
31
30
29
28
27
26
25
24
23
22
21
Control Applications
High-Speed DSP Front-End
Automotive Applications
2
3
AINM
4
REFIN
REFOUT
REFP
REFM
AGND
5
DESCRIPTION
6
BV
7
DD
The THS10082 is a CMOS, low-power, 10-bit, 8 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 allow for programming the ADC into the desired
mode. The THS10082 consists of two 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
BGND
8
D6
D7
9
AV
10
11
12
13
14
15
16
DD
D8
D9
CS0
CS1
RA0
RA1
20 WR (R/W)
19
18
17
RD
DV
CONV_CLK (CONVST)
DATA_AV
DD
DGND
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.
ꢑꢘ ꢌ ꢕꢒ ꢖ ꢀꢉ ꢌꢎ ꢕ ꢍꢀꢍ ꢙꢚ ꢛꢜ ꢝ ꢞꢟ ꢠꢙꢜꢚ ꢙꢡ ꢢꢣ ꢝ ꢝ ꢤꢚꢠ ꢟꢡ ꢜꢛ ꢥꢣꢦ ꢧꢙꢢ ꢟꢠꢙ ꢜꢚ ꢨꢟ ꢠꢤꢩ ꢑꢝ ꢜꢨꢣ ꢢꢠꢡ
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ꢑꢝ ꢜ ꢨꢣꢢ ꢠ ꢙꢜ ꢚ ꢥꢝ ꢜ ꢢ ꢤ ꢡ ꢡ ꢙꢚ ꢮ ꢨꢜ ꢤ ꢡ ꢚꢜꢠ ꢚꢤ ꢢꢤ ꢡꢡ ꢟꢝ ꢙꢧ ꢭ ꢙꢚꢢ ꢧꢣꢨ ꢤ ꢠꢤ ꢡꢠꢙ ꢚꢮ ꢜꢛ ꢟꢧ ꢧ ꢥꢟ ꢝ ꢟꢞ ꢤꢠꢤ ꢝ ꢡꢩ
Copyright 2002, Texas Instruments Incorporated
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www.ti.com
SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
These devices have limited built-in ESD protection. The
leads should be shorted together or the device placed in
conductive foam during storage or handling to prevent
electrostatic damage to the MOS gates.
ORDERING INFORMATION
PACKAGED DEVICE
T
A
TSSOP
(DA)
0°C to 70°C
THS10082CDA
THS10082IDA
–40°C to 85°C
ABSOLUTE MAXIMUM RATINGS
over operating free-air temperature range unless otherwise noted
(1)
THS10082
DGND to DV
BGND to BV
–0.3 V to 6.5 V
–0.3 V to 6.5 V
–0.3 V to 6.5 V
DD
Supply voltage range
DD
DD
AGND to AV
Analog input voltage range
Reference input voltage
Digital input voltage range
AGND –0.3 V to AV
DD
+ 1.5 V
+ 0.3 V
+ 0.3 V
–0.3 V + AGND to AV
DD
–0.3 V to BV /DV
DD DD
Operating virtual junction temperature range, T
–40°C to 150°C
0°C to 70°C
–40°C to 85°C
–65°C to 150°C
260°C
J
THS10082C
THS10082I
Operating free-air temperature range, T
A
Storage temperature range, T
stg
Lead temperature 1,6 mm (1/16 inch) from case for 10 seconds
(1)
Stresses beyond those listed under “absolute maximum ratings” 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 “recommended operating conditions” is not
implied. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.
RECOMMENDED OPERATING CONDITIONS
POWER SUPPLY
MIN NOM
MAX
5.25
5.25
5.25
UNIT
AV
DD
4.75
3
5
3.3
3.3
Supply voltage
DV
V
DD
DD
BV
3
ANALOG AND REFERENCE INPUTS
MIN NOM
MAX
UNIT
Analog input voltage in single-ended configuration
V
V
V
V
V
V
V
REFM
REFP
4
Common-mode input voltage V
in differential configuration
(optional)
1
2.5
CM
External reference voltage,V
3.5 AV –1.2
REFP
DD
External reference voltage, V
REFM
(optional)
1.4
1.5
2
Input voltage difference, REFP – REFM
DIGITAL INPUTS
MIN NOM
MAX
UNIT
V
BV
BV
BV
BV
DV
DV
DV
= 3 V
2
DD
DD
DD
DD
DD
DD
DD
High-level input voltage, V
IH
= 5.25 V
2.6
V
= 3 V
0.6
0.6
V
Low-level input voltage, V
IL
= 5.25 V
V
Input CONV_CLK frequency
= 3 V to 5.25 V
= 3 V to 5.25 V
= 3 V to 5.25 V
0.1
62
62
0
8
MHz
ns
ns
CONV_CLK pulse duration, clock high, t
83
83
5000
5000
70
w(CONV_CLKH)
CONV_CLK pulse duration, clock low, t
w(CONV_CLKL)
THS10082CDA
THS10082IDA
Operating free-air temperature, T
°C
A
–40
85
2
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
ELECTRICAL CHARACTERISTICS
over recommended operating conditions, DV
DIGITAL SPECIFICATIONS
PARAMETER
= 3.3 V, AV
DD
= 5 V, V = internal (unless otherwise noted)
REF
DD
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Digital inputs
I
I
High-level input current
Low-level input current
Input capacitance
DV
= digital inputs
Digital input = 0 V
–50
–50
50
50
µA
µA
pF
IH
DD
IL
C
5
i
Digital outputs
V
V
High-level output voltage
Low-level output voltage
I
I
= –50 µA, BV
= –50 µA, BV
= 3.3 V, 5 V
= 3.3 V, 5 V
BV –0.5
V
OH
OH
DD
DD
0.4
10
V
OL
OL
DD
I
High-impedance-state output current
Output capacitance
CS1 = DGND, CS0 = DV
DD
–10
µA
pF
pF
OZ
C
5
O
L
C
Load capacitance at databus D0 –D9
30
ELECTRICAL CHARACTERISTICS
over recommended operating conditions, AV
DC SPECIFICATIONS
PARAMETER
= 5 V, DV
DD
= BV
DD
= 3.3 V, f = 8 MSPS, V = internal (unless otherwise noted)
REF
DD
s
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Resolution
10
Bits
Accuracy
Integral nonlinearity, INL
Differential nonlinearity, DNL
±1
±1
LSB
LSB
LSB
LSB
LSB
After calibration in single-ended mode
After calibration in differential mode
±5
Offset error
–10
–10
10
10
Gain error
Analog input
Input capacitance
15
pF
Input leakage current
Internal voltage reference
V
AIN
= V
REFM
to V
REFP
±10
µA
V
V
Accuracy
3.3
1.4
3.5
1.5
50
3.7
1.6
V
REFP
Accuracy
V
PPM/°C
µV
REFM
Temperature coefficient
Reference noise
Accuracy, REFOUT
100
2.475
2.5 2.525
V
Power supply
I
I
I
I
Analog supply current
Digital supply current
Buffer supply current
AV
AV
AV
AV
AV
AV
= 5 V, BV
= 5 V, BV
= 5 V, BV
= 5 V, BV
= 5 V, DV
= 5 V, DV
= DV
= DV
= DV
= DV
= BV
= BV
= 3.3 V
= 3.3 V
= 3.3 V
= 3.3 V
= 3.3 V
= 3.3 V
36
0.5
1.5
40
1
mA
mA
mA
mA
mW
mW
DDA
DD
DD
DD
DD
DD
DD
DD
DD
DD
DD
DD
DD
DD
DD
DD
DD
DD
DD
DDD
4
DDB
Analog supply current in power-down mode
Power dissipation
8
DD_AP
P
186
30
216
D
Power dissipation in powerdown
3
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
ELECTRICAL CHARACTERISTICS
over recommended operating conditions, V
= internal, f = 8 MHz, f = 2 MHz at –1 dB (unless otherwise noted)
s I
REF
AC SPECIFICATIONS, AV
DD
= 5 V, BV
DD
= DV = 3.3 V, C < 30 pF
DD L
PARAMETER
TEST CONDITIONS
MIN
56
TYP
59
MAX
UNIT
Differential mode
dB
dB
dB
dB
dB
dB
Bits
Bits
dB
dB
SINAD Signal-to-noise ratio + distortion
(1)
Single-ended mode
Differential mode
Single-ended mode
Differential mode
Single-ended mode
Differential mode
Single-ended mode
Differential mode
Single-ended mode
55
58
59
61
SNR
Signal-to-noise ratio
(1)
60
–67
–63
9.5
9.35
65
–61
THD
Total harmonic distortion
Effective number of bits
Spurious free dynamic range
9
ENOB
SFDR
(1)
61
64
Analog Input
Full-power bandwidth with a source impedance of 150 Ω in
differential configuration.
Full-scale sinewave, –3 dB
Full-scale sinewave, –3 dB
100-mVpp sinewave, –3 dB
100-mVpp sinewave, –3 dB
96
54
96
54
MHz
MHz
MHz
MHz
Full-power bandwidth with a source impedance of 150 Ω in
single-ended configuration.
Small-signal bandwidth with a source impedance of 150 Ω in
differential configuration.
Small-signal bandwidth with a source impedance of 150 Ω in
single-ended configuration.
(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.
(1)
TIMING REQUIREMENTS
AV
DD
= DV
DD
= 5 V, BV
DD
= 3.3 V, V = internal, C < 30 pF
REF L
PARAMETER
TEST CONDITIONS
MIN
TYP
5
MAX
UNIT
ns
t
t
Delay time
Delay time
d(DATA_AV)
5
ns
d(o)
CONV
CLK
t
Latency
5
pipe
(1)
See Figure 27.
(1)
TIMING SPECIFICATION OF THE SINGLE CONVERSION MODE
PARAMETER
TEST CONDITIONS
MIN
TYP
MAX
UNIT
t
c
Clock cycle of the internal clock oscillator
117
125
133
ns
One analog input
Two analog inputs
1.5×t
c
t
t
Pulse duration, CONVST
Aperture time
ns
ns
w1
2.5×t
c
1
d(A)
One analog input
2×t
3×t
Delay time between consecutive start of
single conversion
c
t
ns
ns
ns
ns
ns
2
Two analog inputs
c
One analog input, TL = 1
Two analog inputs, TL = 2
One analog input, TL = 4
Two analog inputs, TL = 4
One analog input, TL = 8
Two analog inputs, TL = 8
One analog input, TL = 14
Two analog inputs, TL = 12
6.5×t +15
c
7.5×t +15
c
3×t +6.5×t +15
2
c
t
2
+7.5×t +15
c
Delay time, DATA_AV becomes active for the
trigger level condition: TRIG0 = 1, TRIG1 = 1
t
d(DATA_AV)
7×t +6.5×t +15
2
c
3×t +7.5×t +15
2
c
13×t +6.5×t +15
2
c
13×t +6.5×t +15
2
c
(1)
See Figure 26.
4
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
Terminal Functions
TERMINAL
NAME
AINP
AINM
AV
I/O
DESCRIPTION
NO.
30
29
23
24
7
I
I
I
I
I
I
I
Analog input, single-ended or positive input of differential channel A
Analog input, single-ended or negative input of differential channel A
Analog supply voltage
DD
AGND
BV
Analog ground
Digital supply voltage for buffer
DD
BGND
8
Digital ground for buffer
CONV_CLK
(CONVST)
15
Digital input. This input is used to apply an external conversion clock in the continuous conversion mode. In
the 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
21
16
I
I
Chip select input (active low)
Chip select input (active high)
CS1
DATA_AV
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
18
I
I
Digital ground. Ground reference for digital circuitry.
Digital supply voltage
DV
DD
D0–D9
1–6, 9–12
13
I/O/Z Digital input, output; D0 = LSB
RA0
I
Digital input. RA0 is used as an address line (RA0) for the control register. This is required for writing to
control register 0 and control register 1. See Table 8.
RA1
14
32
28
26
I
Digital input. RA1 is 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.
OV_FL
REFIN
REFP
O
I
Overflow output. Indicates whether an overflow in the FIFO occurred. OV_FL is set to active high level if an
overflow occurs. It is set back to low level with a reset of the THS10082 or a reset of the FIFO.
Common-mode reference input for the analog input channels. It is recommended that this pin be
connected to the reference output REFOUT.
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.
RESET
31
27
I
Hardware reset of the THS10082. Sets the control register to default values.
REFOUT
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.
(1)
RD
19
20
I
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.
(1)
WR (R/W)
This input is programmable. It functions as a read-write input (R/W) and can also be configured as a
write-onlyinput (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.
5
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
FUNCTIONAL BLOCK DIAGRAM
AV
DD
DV
DD
3.5 V
1.5 V
2.5 V
REFP
1.225 V
REF
REFOUT
REFM
REFIN
DATA_AV
OV_FL
REFP
REFM
10
BV
DD
Single-Ended
and/or
Differential
MUX
10-Bit
Pipeline
ADC
10
FIFO
16 × 10
D0
D1
D2
D3
D4
D5
D6
D7
D8
D9
S/H
AINP
AINM
S/H
Buffers
CONV_CLK (CONVST)
RA0
RA1
CS0
CS1
Logic
and
Control
Control
Register
BGND
RD
WR (R/W)
RESET
AGND
DGND
6
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
TYPICAL CHARACTERISTICS
TOTAL HARMONIC DISTORTION
vs
SAMPLING FREQUENCY (SINGLE-ENDED)
SIGNAL-TO-NOISE AND DISTORTION
vs
SAMPLING FREQUENCY (SINGLE-ENDED)
80
75
70
65
60
55
50
45
40
65
60
55
50
45
40
AV
f
= 5 V, DV
= BV
= 3 V,
= 500 kHz, AIN = –1 dB FS
AV
f
= 5 V, DV
= BV
= 3 V,
= 500 kHz, AIN = –1 dB FS
DD
IN
DD
DD
DD
IN
DD
DD
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
f
s
– Sampling Frequency – MHz
f
s
– Sampling Frequency – MHz
Figure 1
Figure 2
SIGNAL-TO-NOISE
vs
SPURIOUS FREE DYNAMIC RANGE
vs
SAMPLING FREQUENCY (SINGLE-ENDED)
SAMPLING FREQUENCY (SINGLE-ENDED)
65
60
55
50
45
40
90
85
80
75
70
65
60
55
50
45
40
AV
f
= 5 V, DV
= BV
= 3 V,
= 500 kHz, AIN = –1 dB FS
DD
IN
DD
DD
AV
f
= 5 V, DV
= BV
= 3 V,
= 500 kHz, AIN = –1 dB FS
DD
IN
DD
DD
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
f
s
– Sampling Frequency – MHz
f
s
– Sampling Frequency – MHz
Figure 3
Figure 4
7
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
TYPICAL CHARACTERISTICS
TOTAL HARMONIC DISTORTION
SIGNAL-TO-NOISE AND DISTORTION
vs
vs
SAMPLING FREQUENCY (DIFFERENTIAL)
SAMPLING FREQUENCY (DIFFERENTIAL)
85
80
75
70
65
60
55
50
45
40
65
60
55
50
45
40
AV
f
= 5 V, DV
= BV
= 3 V,
= 500 kHz, AIN = –1 dB FS
AV
f
= 5 V, DV
= BV
= 3 V,
= 500 kHz, AIN = –1 dB FS
DD
IN
DD
DD
DD
IN
DD
DD
0
1
2
3
4
5
6
7
8
9
0
1
2
3
4
5
6
7
8
9
f
s
– Sampling Frequency – MHz
f
s
– Sampling Frequency – MHz
Figure 5
Figure 6
SIGNAL-TO-NOISE
vs
SPURIOUS FREE DYNAMIC RANGE
vs
SAMPLING FREQUENCY (DIFFERENTIAL)
SAMPLING FREQUENCY (DIFFERENTIAL)
65
60
55
50
45
40
90
85
80
75
70
65
60
55
50
45
40
AV
f
= 5 V, DV
= BV
= 3 V,
= 500 kHz, AIN = –1 dB FS
DD
IN
DD
DD
AV
f
= 5 V, DV
= BV
= 3 V,
= 500 kHz, AIN = –1 dB FS
DD
IN
DD
DD
0
1
2
f
3
4
5
6
7
8
9
0
1
2
s
3
4
5
6
7
8
9
– Sampling Frequency – MHz
f
– Sampling Frequency – MHz
s
Figure 7
Figure 8
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
TYPICAL CHARACTERISTICS
SIGNAL-TO-NOISE AND DISTORTION
vs
TOTAL HARMONIC DISTORTION
vs
INPUT FREQUENCY (DIFFERENTIAL)
INPUT FREQUENCY (DIFFERENTIAL)
80
75
70
65
60
55
50
45
40
65
60
55
50
45
40
AV
f
= 5 V, DV
= BV
= 3 V,
= 8 MSPS, AIN = –1 dB FS
DD
s
DD
DD
AV
f
= 5 V, DV
= BV
= 3 V,
= 800 MSPS, AIN = –1 dB FS
DD
s
DD
DD
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
f – Input Frequency – MHz
i
f – Input Frequency – MHz
i
Figure 9
Figure 10
SPURIOUS FREE DYNAMIC RANGE
vs
INPUT FREQUENCY (DIFFERENTIAL)
90
85
80
75
70
65
60
55
50
45
AV
f
= 5 V, DV
= BV
= 3 V,
= 8 MSPS, AIN = –1 dB FS
DD
s
DD
DD
40
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
f – Input Frequency – MHz
i
Figure 11
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
TYPICAL CHARACTERISTICS
SIGNAL-TO-NOISE
TOTAL HARMONIC DISTORTION
vs
vs
INPUT FREQUENCY (DIFFERENTIAL)
INPUT FREQUENCY (SINGLE-ENDED)
65
60
80
75
70
65
60
55
50
45
40
AV
f
= 5 V, DV
= BV
= 3 V,
= 8 MSPS, AIN = –1 dB FS
55
50
45
40
DD
s
DD
DD
AV
f
= 5 V, DV
= BV
= 3 V,
= 8 MSPS, AIN = –1 dB FS
DD
s
DD
DD
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
f – Input Frequency – MHz
i
f – Input Frequency – MHz
i
Figure 12
Figure 13
SIGNAL-TO-NOISE AND DISTORTION
vs
INPUT FREQUENCY (SINGLE-ENDED)
SPURIOUS FREE DYNAMIC RANGE
vs
INPUT FREQUENCY (SINGLE-ENDED)
65
60
55
50
45
40
90
85
80
75
70
65
60
55
50
45
40
AV
= 5 V, DV
= BV
= 3 V,
f = 8 MSPS, AIN = –1 dB FS
DD
s
DD
DD
AV
f
= 5 V, DV
= BV
= 3 V,
= 8 MSPS, AIN = –1 dB FS
DD
s
DD
DD
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
f – Input Frequency – MHz
i
f – Input Frequency – MHz
i
Figure 14
Figure 15
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
TYPICAL CHARACTERISTICS
SIGNAL-TO-NOISE
vs
EFFECTIVE NUMBER OF BITS
vs
INPUT FREQUENCY (DIFFERENTIAL)
SAMPLING FREQUENCY (SINGLE-ENDED)
65
60
55
50
45
40
11.0
10.5
10.0
9.5
9.0
AV
f
= 5 V, DV
= BV
= 3 V,
= 500 kHz, AIN = –1 dB FS
DD
IN
DD
DD
8.5
AV
f
= 5 V, DV
= BV
= 3 V,
= 8 MSPS, AIN = –1 dB FS
DD
s
DD
DD
8.0
7.5
7.0
6.5
6.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0
1
2
3
4
5
6
7
8
9
f – Input Frequency – MHz
i
f
s
– Sampling Frequency – MHz
Figure 16
Figure 17
EFFECTIVE NUMBER OF BITS
vs
EFFECTIVE NUMBER OF BITS
vs
INPUT FREQUENCY (SINGLE-ENDED)
SAMPLING RATE (DIFFERENTIAL)
11.0
10.5
10.0
9.5
11.0
10.5
10.0
9.5
9.0
9.0
AV
f
= 5 V, DV
= BV
= 3 V,
= 8 MSPS, AIN = –1 dB FS
DD
s
DD
DD
8.5
8.5
AV
f
= 5 V, DV
= BV
= 3 V,
= 500 kHz, AIN = –1 dB FS
DD
IN
DD
DD
8.0
8.0
7.5
7.5
7.0
7.0
6.5
6.5
6.0
6.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
0
1
2
s
3
4
5
6
7
8
9
f – Input Frequency – MHz
i
f
– Sampling Frequency – MHz
Figure 19
Figure 18
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
TYPICAL CHARACTERISTICS
EFFECTIVE NUMBER OF BITS
vs
INPUT FREQUENCY (DIFFERENTIAL)
11.0
10.5
10.0
9.5
9.0
AV
f
= 5 V, DV
= BV
= 3 V,
= 8 MSPS, AIN = –1 dB FS
DD
s
DD
DD
8.5
8.0
7.5
7.0
6.5
6.0
0.0
0.5
1.0
1.5
2.0
2.5
3.0
3.5
4.0
f – Input Frequency – MHz
i
Figure 20
GAIN
vs
INPUT FREQUENCY (SINGLE-ENDED)
5
0
–5
AV
f
= 5 V, DV
= BV
= 3 V,
= 8 MSPS, AIN = –1 dB FS
–10
–15
–20
–25
DD
s
DD
DD
–30
0
20
40
60
80
100
120
f – Input Frequency – MHz
i
Figure 21
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
TYPICAL CHARACTERISTICS
DIFFERENTIAL NONLINEARITY
vs
ADC CODE
1.0
0.8
AV
= 5 V,
= 3 V,
= 8 MSPS
DD
DV
= BV
DD
f
DD
0.6
s
0.4
0.2
–0.0
–0.2
–0.4
–0.6
–0.8
–1.0
0
256
512
768
1024
Code
Figure 22
INTEGRAL NONLINEARITY
vs
ADC CODE
1.0
0.8
0.6
AV
= 5 V,
= 3 V,
= 8 MSPS
DD
DV
= BV
DD
f
DD
0.4
s
0.2
–0.0
–0.2
–0.4
–0.6
–0.8
–1.0
0
256
512
768
1024
Code
Figure 23
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
TYPICAL CHARACTERISTICS
FAST FOURIER TRANSFORM
vs
FREQUENCY
(4096 POINTS) (SINGLE-ENDED MODE)
0
–20
AV
DD
= 5 V, DV
DD
= BV = 3 V,
DD
f
s
= 8 MHz, AIN = –1 dB FS, f = 1.25 MHz
IN
–40
–60
–80
–100
–120
–140
0
500000
1000000 1500000 2000000 2500000 3000000 3500000 4000000
f – Frequency – Hz
Figure 24
FAST FOURIER TRANSFORM
vs
FREQUENCY
(4096 POINTS) (DIFFERENTIAL MODE)
0
–20
AV
DD
= 5 V, DV
DD
= BV = 3 V,
DD
f
s
= 8 MHz, AIN = –0.5 dB FS, f = 1.25 MHz
IN
–40
–60
–80
–100
–120
–140
0
500000
1000000 1500000 2000000 2500000 3000000 3500000 4000000
f – Frequency – Hz
Figure 25
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
DETAILED DESCRIPTION
Reference Voltage
The THS10082 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 THS10082 consists of two 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.
Analog-to-Digital Converter
The THS10082 uses a 10-bit pipelined multistaged architecture with four 1-bit stages followed by four 2-bit stages, which
achieves a high sample rate with low power consumption. The THS10082 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.
DATA_AV
In continuous conversion mode, the first DATA_AV signal is delayed by (7+TL) cycles of the CONV_CLK after a FIFO reset.
This is due to the latency of the pipeline architecture of the THS10082.
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
NUMBER OF
CHANNELS
MAXIMUM CONVERSION
RATE PER CHANNEL
CHANNEL CONFIGURATION
One single-ended channel
1
2
1
8 MSPS
4 MSPS
8 MSPS
Two single-ended channels
One differential channel
The maximum conversion rate in the continuous conversion mode per channel, fc, is given by:
8 MSPS
# channels
fc +
Table 2 shows the maximum conversion rate in the single conversion mode.
(1)
Table 2. Maximum Conversion Rate in Single Conversion Mode
NUMBER OF
CHANNELS
MAXIMUM CONVERSION
RATE PER CHANNEL
CHANNEL CONFIGURATION
1 single-ended channel
1
2
1
4 MSPS
2 single-ended channels
1 differential channel
2.67 MSPS
4 MSPS
(1)
The maximum conversion rate with respect to the typical internal oscillator speed [i.e., 8 MHz × (tc/t2)].
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
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 26 shows the timing of the single conversion mode. In this mode, up to two analog input channels can be selected
to be sampled simultaneously (see Table 2).
t
2
CONVST
AIN
t
t
1
1
t
d(A)
Sample N
t
DATA_AV
DATA_AV,
Trigger Level = 1
Figure 26. 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.
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 27 shows the timing of continuous conversion mode when one analog input channel is selected. The maximum
throughput rate is 8 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.
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
Sample N
Channel 1
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
AIN
t
d(A)
t
d(pipe)
w(CONV_CLKL)
50%
t
t
w(CONV_CLKH)
CONV_CLK
50%
t
t
d(O)
c
Data Into
FIFO
Data N–5
Channel 1
Data N–4
Channel 1
Data N–3
Channel 1
Data N–2
Channel 1
Data N–1
Channel 1
Data N
Channel 1
Data N+1
Channel 1
Data N+2
Channel 1
Data N+3
Channel 1
t
d(DATA_AV)
DATA_AV,
Trigger Level = 1
t
d(DATA_AV)
DATA_AV,
Trigger Level = 4
Figure 27. Timing of Continuous Conversion Mode (1-channel operation)
Figure 28 shows the timing of continuous conversion mode when two analog input channels are selected. The maximum
throughput rate per channel is 4 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
Channel 1,2
Sample N+1
Channel 1,2
Sample N+2
Channel 1,2
Sample N+3
Channel 1,2
Sample N+4
Channel 1,2
AIN
t
d(A)
t
d(Pipe)
w(CONV_CLKL)
50%
t
t
w(CONV_CLKH)
CONV_CLK
50%
t
c
t
d(O)
Data Into
FIFO
Data N–3
Channel 2
Data N–2
Channel 1
Data N–2
Channel 2
Data N–1
Channel 1
Data N–1
Channel 2
Data N
Channel 1
Data N
Channel 2
Data N+1
Channel 1
Data N+1
Channel 2
t
d(DATA_AV)
DATA_AV,
Trigger Level = 2
t
d(DATA_AV)
DATA_AV,
Trigger Level = 4
Figure 28. Timing of Continuous Conversion Mode (2-Channel Operation)
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
DIGITAL OUTPUT DATA FORMAT
The digital output data format of the THS10082 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
AIN = V
DIGITAL OUTPUT CODE
3FFh
200h
000h
REFP
AIN = (V
+ V )/2
REFM
REFP
AIN = V
REFM
Table 4. Twos Complement Output Format for Single-Ended Configuration
SINGLE-ENDED, TWOS COMPLEMENT
ANALOG INPUT VOLTAGE
AIN = V
DIGITAL OUTPUT CODE
1FFh
000h
200h
REFP
AIN = (V
+ V )/2
REFM
REFP
AIN = V
REFM
Table 5. Binary Output Format for Differential Configuration
DIFFERENTIAL, BINARY OUTPUT
ANALOG INPUT VOLTAGE
= AINP – AINM
DIGITAL OUTPUT CODE
V
in
= V
V
REF
– V
REFM
REFP
V
= V
3FFh
200h
000h
in
REF
V
= 0
in
= –V
V
in
REF
Table 6. Twos Complement Output Format for Differential Configuration
DIFFERENTIAL, BINARY OUTPUT
ANALOG INPUT VOLTAGE
= AINP – AINM
DIGITAL OUTPUT CODE
V
in
= V
V
REF
– V
REFM
REFP
V
= V
1FFh
000h
200h
in
REF
V
= 0
in
= –V
V
in
REF
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
FIFO DESCRIPTION
In order to facilitate an efficient connection to today’s processors, the THS10082 is supplied with a FIFO. This integrated
FIFO enables a problem-free processing of data with today’s processors. The FIFO is provided as a flexible circular buffer.
The circular buffer integrated in the THS10082 stores up to 16 conversion values. Therefore, the amount of interrupts to
be served by a processor can be reduced significantly.
16
1
15
2
Read Pointer
14
3
13
12
4
5
Trigger Pointer
6
11
Data in FIFO
Free
7
10
8
9
Write Pointer
Figure 29. Circular Buffer
The converted data of the THS10082 is automatically written into the FIFO. To control the writing and reading process, a
write pointer, a read pointer and a trigger pointer are used. The read pointer always shows the location which is read next.
The write pointer indicates the location which contains the last written sample. With a selection of multiple analog input
channels, the converted values are written in a predefined sequence to the circular buffer (autoscan mode). In this way,
the channel information for the reading processor is continually maintained.
The FIFO can be programmed through the control register of the ADC. The user has the ability to select a specific trigger
level according to Table 13 in order to choose the configuration which best fits the application. The FIFO provides the signal
DATA_AV, which signals the processor to read the amount of data equal to the trigger level selected in Table 13. The signal
DATA_AV becomes active when the trigger condition is satisfied. The trigger condition is satisfied when as many values
as selected for the trigger level are written into the FIFO.
The signal DATA_AV could be connected to an interrupt input of a processor. In every interrupt service routine call, the
processor must read the amount of data equal to the trigger level from the ADC. The first data represents the first channel
according to the autoscan mode, which is shown in Table 10. The channel information is, therefore, always maintained.
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
READING DATA FROM THE FIFO
The THS10082 informs the connected processor via the digital output DATA_AV (data available) that a block of conversion
values is ready to be read. The block size to be read is always equal to the setting of the trigger level. The selectable trigger
levels depend on the number of selected analog input channels. For example, when choosing one analog input, a trigger
level of 1, 4, 8, and 14 can be selected. The following figures demonstrate the principle of reading the data (the READ signal
is asynchronous to CONV_CLK).
In Figure 30, a trigger level of 1 is selected. The control signal DATA_AV is set to an active low pulse. This means that the
connected processor has the task to read 1 value from the ADC after every DATA_AV low pulse.
CONV_CLK
DATA_AV
READ
Figure 30. Trigger Level 1 Selected
In Figure 31, a trigger level of 4 is selected. The control signal DATA_AV is set to an active low pulse. This means that the
connected processor has the task to read 4 values from the ADC after every DATA_AV low pulse.
CONV_CLK
DATA_AV
READ
Figure 31. Trigger Level 4 Selected
In Figure 32, a trigger level of 8 is selected. The control signal DATA_AV is set to an active low pulse. This means that the
connected processor has the task to read 8 values from the ADC after every DATA_AV low pulse.
CONV_CLK
DATA_AV
READ
Figure 32. Trigger Level 8 Selected
In Figure 33, a trigger level of 14 is selected. The control signal DATA_AV is set to an active low pulse. This means that
the connected processor has the task to read 14 values from the ADC after every DATA_AV low pulse.
CONV_CLK
DATA_AV
READ
Figure 33. Trigger Level 14 Selected
As shown in Figure 30 through Figure 33, READ, is the logical combination of CS0, CS1, and RD.
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
ADC CONTROL REGISTER
The THS10082 contains two 10-bit wide control registers (CR0, CR1) in order to program the device into the desired mode.
The bit definitions of both control registers are shown in Table 7.
Table 7. Bit Definitions of Control Register CR0 and CR1
REG
CR0
CR1
BIT 9
TEST1
BIT 8
TEST0
OFFSET
BIT 7
SCAN
BIN/2’s
BIT 6
DIFF1
R/W
BIT 5
DIFF0
BIT 4
BIT 3
CHSEL0
TRIG1
BIT 2
PD
BIT 1
MODE
FRST
BIT 0
VREF
CHSEL1
DATA_T
RESERVED
DATA_P
TRIG0
RESET
Writing to Control Register 0 and Control Register 1
The 10-bit wide control register 0 and control register 1 can be programmed by addressing the desired control register and
writing the register value to the ADC. The addressing is performed with the upper bits RA0 and RA1. During this write
process, the data bits D0 to D9 contain the desired control register value. Table 8 shows the addressing of each control
register.
Table 8. Control Register Addressing
D0 – D9
RA0
RA1
Addressed Control Register
Control register 0
Desired register value
Desired register value
Desired register value
Desired register value
0
1
0
1
0
0
1
1
Control register 1
Reserved for future
Reserved for future
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
INITIALIZATION OF THE THS10082
The initialization of the THS10082 should be done according to the configuration flow shown in Figure 34.
Start
No
Use Default
Values?
Yes
Write 0x401 to
Write 0x401 to
THS10082
THS10082
(Set Reset Bit in CR1)
(Set Reset Bit in CR1)
Clear RESET By
Writing 0x400 to
CR1
Clear RESET By
Writing 0x400 to
CR1
Write The User
Configuration to
CR0
Write The User
Configuration to
CR1 (Can Include
FIFO Reset, Must
Exclude RESET)
Continue
Figure 34. THS10082 Configuration Flow
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
ADC CONTROL REGISTERS
Control Register 0, Write Only (see Table 8)
BIT 11
BIT 10
BIT 9
BIT 8
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
0
0
TEST1
TEST0
SCAN
DIFF1
DIFF0
CHSEL1 CHSEL0
PD
MODE
VREF
Table 9. Control Register 0 Bit Functions
RESET
VALUE
BITS
NAME
FUNCTION
0
0
VREF
Vref select:
Bit 0 = 0 → The internal reference is selected
Bit 0 = 1 → The external reference voltage is selected
1
0
MODE
Continuous conversion mode/single conversion mode
Bit 1 = 0 → Continuous conversion mode is selected
An external clock signal is applied to the CONV_CLK input in this mode. With every falling edge of the
CONV_CLK signal a new converted value is written into the FIFO.
Bit 1 = 1 → Single conversion mode is selected
In this mode, the CONV_CLK input functions as a CONVST input. A single conversion is initiated on the
THS10082by 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 signal DATA_AV (data available) becomes active when the trigger condition is
satisfied.
2
0
PD
Power down.
Bit 2 = 0 → The ADC is active
Bit 2 = 1 → Power down
The reading and writing to and from the digital outputs is possible during power down. It is also possible to
read out the FIFO.
3, 4
5,6
7
0,0
1,0
0
CHSEL0,
CHSEL1
Channel select
Bit 3 and bit 4 select the analog input channel of the ADC. Refer to Table 10.
DIFF0, DIFF1 Number of differential channels
Bit 5 and bit 6 contain information about the number of selected differential channels. See Table 10.
SCAN
Autoscan enable
Bit 7 enables or disables the autoscan function of the ADC. See Table 10.
8,9
0,0
TEST0,
TEST1
Test input enable
Bit 8 and bit 9 control the test function of the ADC. Three different test voltages can be measured. This
feedback allows the check of all hardware connections and the ADC operation.
See Table 11 for selection of the three different test voltages.
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
ANALOG INPUT CHANNEL SELECTION
The analog input channels of the THS10082 can be selected via bits 3 to 7 of control register 0. One single channel
(single-ended or differential) is selected via bit 3 of control register 0. Bit 5 controls the selection between single-ended and
differential configuration. Bit 6 selects the autoscan mode, if more than one input channel is selected. Table 10 shows the
possible selections.
Table 10. Analog Input Channel Configurations
BIT 7
SCAN
BIT 6
DIFF1
BIT 5
DIFF0
BIT 4
CHSEL1 CHSEL0
BIT 3
DESCRIPTION OF THE SELECTED INPUTS
Analog input AINP (single ended)
0
0
0
0
0
0
1
1
1
1
1
1
0
0
1
1
1
1
1
1
1
1
1
1
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
1
1
1
1
1
1
1
0
0
0
0
1
1
0
0
0
1
1
0
1
1
0
1
1
0
0
0
1
1
1
1
0
0
1
1
0
0
0
1
1
0
1
0
1
1
0
0
1
0
1
1
0
0
1
1
0
1
0
1
0
1
1
0
1
1
0
1
0
1
0
0
1
0
0
1
0
1
0
1
Analog input AINM (single ended)
Reserved
Reserved
Differential channel (AINP–AINM)
Reserved
Autoscan two single-ended channels: AINP, AINM, AINP, …
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Reserved
Test Mode
The test mode of the ADC is selected via bit 8 and bit 9 of control register 0. The different selections are shown in Table 11.
Table 11. Test Mode
BIT 9
TEST1 TEST0
BIT 8
OUTPUT RESULT
0
0
1
1
0
1
0
1
Normal mode
V
REFP
)+(V
((V
))/2
REFP
REFM
V
REFM
Three different options can be selected. This feature allows support testing of hardware connections between the ADC and
the processor.
24
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
Control Register 1, Write Only (see Table 8)
BIT 11
BIT 10
BIT 9
BIT 8
BIT 7
BIT 6
BIT 5
BIT 4
BIT 3
BIT 2
BIT 1
BIT 0
0
1
RESERVED OFFSET
BIN/2s
R/W
DATA_P DATA_T
TRIG1
TRIG0
FRST
RESET
Table 12. Control Register 1 Bit Functions
RESET
VALUE
BITS
NAME
FUNCTION
0
0
RESET
Reset
Writing a 1 into this bit resets the device and sets the control register 0 and control register 1 to the reset values.
In addition the FIFO pointer and offset register is reset. After reset, it takes 5 clock cycles until the first value is
converted and written into the FIFO.
1
0
FRST
FRST: FIFO reset
By writing a 1 into this bit, the FIFO is reset.
2, 3
0,0
TRIG0,
TRIG1
FIFO trigger level
Bit 2 and bit 3 of control register 1 are used to set the trigger level for the FIFO. If the trigger level is reached, the
signal DATA_AV (data available) becomes active according to the settings of DATA_T and DATA_P. This
indicates to the processor that the ADC values can be read. Refer to Table 13.
4
1
DATA_T
DATA_AV type
Bit 4 of control register 1 controls whether the DATA_AV signal is a pulse or static (e.g., for edge or level
sensitive interrupt inputs). If it is set to 0, the DATA_AV signal is static. If it is set to 1, the DATA_AV signal is a
pulse. See Table 14.
5
6
1
0
DATA_P
R/W
DATA_AV polarity
Bit 5 of control register 1 controls the polarity of DATA_AV. If it is set to 1, DATA_AV is active high. If it is set to 0,
DATA_AV is active low. Refer to Table 14.
R/W, RD/WR selection
Bit 6 of control register 1 controls the function of the inputs RD and WR. Whenbit 6 in control register 1 is set to
1, WR becomes a R/W input and RD is disabled. From now on a read is signalled with R/W high and a write with
R/W as a low signal. If bit 6 in control register 1 is set to 0, the input RD becomes a read input and the input WR
becomes a write input.
7
8
0
0
BIN/2s
Complement select
If bit 7 of control register 1 is set to 0, the output value of the ADC is in twos complement. If bit 7 of
control register 1 is set to 1, the output value of the ADC is in binary format. Refer to Table 3 through Table 6.
OFFSET
Offset cancellation mode
Bit 8 = 0 → normal conversion mode
Bit 8 = 1 → offset calibration mode
If a 1 is written into bit 8 of control register 1, the device internally sets the inputs to zero and does a conver-
sion. The conversion result is stored in an offset register and subtracted from all conversions in order to
reduce the offset error.
9
0
RESERVED Always write 0.
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
FIFO TRIGGER LEVEL
Bit 2 and bit 3 (TRIG1, TRIG0) of control register 1 are used to set the trigger level of the FIFO (see Table 13). If the trigger
level is reached, the DATA_AV (data available) signal becomes active according to the setting of the signal DATA_AV to
indicate to the processor that the ADC values can be read.
Table 13 shows four different programmable trigger levels for each configuration. The FIFO trigger level, which can be
selected, is dependent on the number of input channels. One channel is considered as two inputs in differential
configuration, or one single-ended input. The processor, therefore, always reads the data from the FIFO in the same order
and is able to distinguish between the channels.
Table 13. FIFO Trigger Level
TRIGGER LEVEL
FOR 1 CHANNEL
(ADC values)
TRIGGER LEVEL
FOR 2 CHANNELS
(ADC values)
BIT 3
TRIG1
BIT 2
TRIG0
0
0
1
1
0
1
0
1
01
04
08
14
02
04
08
12
TIMING AND SIGNAL DESCRIPTION OF THE THS10082
The reading from the THS10082 and writing to the THS10082 is performed by using the chip select inputs (CS0, CS1),
the write input WR and the read input RD. The write input is configurable to a combined read/write input (R/W). This is
desired in cases where the connected processor consists of a combined read/write output signal (R/W). The two chip select
inputs can be used to interface easily to a processor.
Reading from the THS10082 takes place by an internal RDint signal, which is generated from the logical combination of
the external signals CS0, CS1, and RD (see Figure 35). This signal is then used to strobe the words out of the FIFO and
to enable the output buffers. The last external signal (either CS0, CS1, or RD) to become valid makes RDint active while
the write input (WR) is inactive. The first of those external signals going to its inactive state then deactivates RDint.
Writing to the THS10082 takes place by an internal WRint signal, which is generated from the logical combination of the
external signals CS0, CS1 and WR. This signal is then used to strobe the control words into the control registers 0 and
1. The last external signal (either CS0, CS1, or WR) to become valid makes WRint active while the read input (RD) is
inactive. The first of those external signals going to its inactive state then deactivates WRint.
Read Enable
CS0
CS1
RD
Write Enable
WR
Control/Data
Registers
Data Bits
Figure 35. Logical Combination of CS0, CS1, RD, and WR
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
DATA_AV Type
Bit 4 and bit 5 (DATA_T, DATA_P) of control register 1 are used to program the signal DATA_AV. Bit 4 of control register 1
determines whether the DATA_AV signal is static or a pulse. Bit 5 of the control register determines the polarity of
DATA_AV. This is shown in Table 14.
Table 14. DATA_AV Type
BIT 5
DATA_P
BIT 4
DATA_T
DATA_AV TYPE
0
0
1
1
0
1
0
1
Active low level
Active low pulse
Active high level
Active high pulse
The signal DATA_AV is set to active when the trigger condition is satisfied. It is set back inactive dependent of the DATA_T
selection (pulse or level).
If level mode is chosen, DATA_AV is set inactive after the first of the TL (TL = trigger level) reads (with the falling edge of
READ). The trigger condition is checked again after TL reads. For single conversion mode, the DATA_AV type should be
programmed to active level mode.
If pulse mode is chosen, the signal DATA_AV is a pulse with a width of one half of a CONV_CLK cycle in continuous
conversion mode.
Read Timing (Using R/W, CS0-Controlled)
Figure 36 shows the read-timing behavior when the WR(R/W) input is programmed as a combined read-write input R/W.
The RD input has to be tied to high-level in this configuration. This timing is called CS0-controlled because CS0 is the last
external signal of CS0, CS1, and R/W which becomes valid.
t
w(CS)
90%
CS0
CS1
10%
10%
t
su(R/W)
t
h(R/W)
90%
90%
R/W
RD
t
a
t
h
90%
90%
D(0–9)
t
d(CSDAV)
90%
DATA_AV
Figure 36. Read Timing Diagram Using R/W (CS0-controlled)
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
(1)
Read Timing Parameter (CS0-Controlled)
PARAMETER
Setup time, R/W high to last CS valid
MIN
0
TYP
MAX
10
UNIT
t
t
t
t
t
t
ns
ns
ns
ns
ns
ns
su(R/W)
Access time, last CS valid to data valid
Delay time, last CS valid to DATA_AV inactive
Hold time, first CS invalid to data invalid
Hold time, first external CS invalid to R/W change
Pulse duration, CS active
0
a
12
d(CSDAV)
h
0
5
5
h(R/W)
w(CS)
10
(1)
CS = CS0
Write Timing (Using R/W, CS0-Controlled)
Figure 37 shows the write-timing behavior when the WR(R/W) input is programmed as a combined read-write input R/W.
The RD input has to be tied to high-level in this configuration. This timing is called CS0-controlled because CS0 is the last
external signal of CS0, CS1, and R/W which becomes valid.
t
w(CS)
90%
CS0
CS1
10%
10%
t
su(R/W)
t
h(R/W)
WR
RD
t
su
t
h
90%
90%
D(0–9)
DATA_AV
Figure 37. Write Timing Diagram Using R/W (CS0-controlled)
(1)
Write Timing Parameter (CS0-Controlled)
PARAMETER
Setup time, R/W stable to last CS valid
MIN
0
TYP
MAX
UNIT
ns
t
t
t
t
t
su(R/W)
Setup time, data valid to first CS invalid
Hold time, first CS invalid to data invalid
Hold time, first CS invalid to R/W change
Pulse duration, CS active
5
ns
su
2
ns
h
5
ns
h(R/W)
w(CS)
10
ns
(1)
CS = CS0
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
INTERFACING THE THS10082 TO THE TMS320C30/31/33 DSP
The following application circuit shows an interface of the THS10082 to the TMS320C30/31/33 DSPs. The read and write
timings (using R/W, CS0-controlled) shown before are valid for this specific interface.
THS10082
TMS320C30/31/33
DV
DD
STRB
A23
CS0
CS1
R/W
RD
R/W
DATA_AV
CONV_CLK
DATA
INTX
TOUT
DATA
INTERFACING THE THS10082 TO THE TMS320C54X USING I/O STROBE
The following application circuit shows an interface of the THS10082 to the TMS320C54x. The read and write timings (using
R/W, CS0-controlled) shown before are valid for this specific interface.
THS10082
TMS320C54x
DV
DD
I/O STRB
CS0
CS1
A15
R/W
RD
R/W
DATA_AV
CONV_CLK
DATA
INTX
BCLK
DATA
Read Timing (Using RD, RD-Controlled)
Figure 38 shows the read-timing behavior when the WR(R/W) input is programmed as a write-input only. The input RD acts
as the read-input in this configuration. This timing is called RD-controlled because RD is the last external signal of CS0,
CS1, and RD which becomes valid.
CS0
CS1
t
t
su(CS)
h(CS)
WR
RD
t
w(RD)
10%
10%
t
a
t
h
90%
90%
D(0–9)
t
d(CSDAV)
90%
DATA_AV
Figure 38. Read Timing Diagram Using RD (RD-controlled)
TMS320C30is a trademark of Texas Instruments.
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
Read Timing Parameter (RD-Controlled)
PARAMETER
Setup time, RD low to last CS valid
MIN
0
TYP
MAX
10
UNIT
t
t
t
t
t
t
ns
ns
ns
ns
ns
ns
su(CS)
Access time, last CS valid to data valid
Delay time, last CS valid to DATA_AV inactive
Hold time, first CS invalid to data invalid
Hold time, RD change to first CS invalid
Pulse duration, RD active
0
a
12
d(CSDAV)
h
0
5
5
h(CS)
w(RD)
10
Write Timing (using WR, WR-Controlled)
Figure 39 shows the write-timing behavior when the WR(R/W) input is programmed as a write input WR only. The input
RD acts as the read input in this configuration. This timing is called WR-controlled because WR is the last external signal
of CS0, CS1, and WR which becomes valid.
CS0
CS1
t
t
h(CS)
su(CS)
t
w(WR)
WR
RD
10%
10%
t
su
t
h
90%
90%
D(0–9)
DATA_AV
Figure 39. Write Timing Diagram Using WR (WR-controlled)
Write Timing Parameter Using WR (WR-Controlled)
PARAMETER
MIN
0
TYP
MAX
UNIT
ns
t
t
t
t
t
Setup time, CS stable to last WR valid
Setup time, data valid to first WR invalid
Hold time, WR invalid to data invalid
Hold time, WR invalid to CS change
Pulse duration, WR active
su(CS)
5
ns
su
2
ns
h
5
ns
h(CS)
w(WR)
10
ns
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
INTERFACING THE THS10082 TO THE TMS320C6201 DSP
The following application circuit shows an interface of the THS10082 to the TMS320C6201. The read (using RD,
RD-controlled) and write timings (using WR, WR-controlled) shown before are valid for this specific interface.
THS10082–1
TMS320C6201
CE1
CS0
CS1
EA20
ARE
RD
AWE
WR
EXT_INT6
DATA
DATA_AV
DATA
TOUT1
TOUT2
EA21
CONV_CLK
THS10082–2
EXT_INT7
CS0
CS1
RD
WR
DATA_AV
DATA
CONV_CLK
ANALOG INPUT CONFIGURATION AND REFERENCE VOLTAGE
The THS10082 features two analog input channels. These can be configured for either single-ended or differential
operation. Best performance is achieved in differential mode. Figure 40 shows a simplified model, where a single-ended
configuration for channel AINP is selected. The reference voltages for the ADC itself are VREFP and VREFM (either internal
or external reference voltage). The analog input voltage range goes from VREFM to VREFP. This means that VREFM defines
the minimum voltage, which can be applied to the ADC. VREFP defines the maximum voltage, which can be applied to the
ADC. The internal reference source provides the voltage VREFM of 1.5 V and the voltage VREFP of 3.5 V. The resulting
analog input voltage swing of 2 V can be expressed by:
V
v AINP v V
REFM
REFP
(1)
V
REFP
10-Bit
ADC
AINP
V
REFM
Figure 40. Single-Ended Input Stage
A differential operation is desired for many applications. Figure 41 shows a simplified model for the analog inputs AINM
and AINP, which are configured for differential operation. This configuration has a few advantages, which are discussed
in the following paragraphs.
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
V
REFP
AINP
AINM
+
V
ADC
10-Bit
ADC
Σ
–
V
REFM
Figure 41. Differential Input Stage
In comparison to the single-ended configuration it can be seen that the voltage (VADC) which is applied at the input of the
ADC is the difference between the input AINP and AINM. This means that VREFM defines the minimum voltage (AINM)
which can be applied to the ADC. VREFP defines the maximum voltage (AINP) which can be applied to the ADC. The voltage
VADC can be calculated as follows:
(
)
V
+ ABS AINP–AINM
ADC
(2)
An advantage to single-ended operation is that the common-mode voltage
AINM ) AINP
V
+
CM
2
(3)
can be rejected in the differential configuration, if the following condition for the analog input voltages is true:
AGND v AINM, AINP v AV
DD
(4)
(5)
1 V v V
v 4 V
CM
In addition to the common-mode voltage rejection, the differential operation allows a dc-offset rejection which is common
to both analog inputs. See Figure 43.
SINGLE-ENDED MODE OF OPERATION
The THS10082 can be configured for single-ended operation using dc or ac coupling. In either case, the input of the
THS10082 must be driven from an operational amplifier that does not degrade the ADC performance. Because the
THS10082 operates from a 5-V single supply, it is necessary to level-shift ground-based bipolar signals to comply with its
input requirements. This can be achieved with dc and ac coupling. An application example is shown for dc-coupled level
shifting in the following section, dc coupling.
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DC COUPLING
An operational amplifier can be configured to shift the signal level according to the analog input voltage range of the
THS10082. The analog input voltage range of the THS10082 goes from 1.5 V to 3.5 V. An op-amp specified for 5-V single
supply can be used as shown in Figure 42.
Figure 42 shows an application example where the analog input signal in the range from –1 V up to 1 V is shifted by an
op-amp to the analog input range of the THS10082 (1.5 V to 3.5 V). The op-amp is configured as an inverting amplifier with
a gain of –1. The required dc voltage of 1.25 V at the noninverting input is derived from the 2.5-V output reference REFOUT
of the THS10082 by using a resistor divider. Therefore, the op-amp output voltage is centered at 2.5 V. The use of ratio
matched, thin-film resistor networks minimizes gain and offset errors.
R
3.5 V
2.5 V
1.5 V
5 V
1 V
0 V
R
THS10082
AINP
_
R
S
–1 V
+
1.25 V
REFIN
REFOUT
R
R
Figure 42. Level-Shift for DC-Coupled Input
DIFFERENTIAL MODE OF OPERATION
For the differential mode of operation, a conversion from single-ended to differential is required. A conversion to differential
signals can be achieved by using an RF-transformer, which provides a center tap. Best performance is achieved in
differential mode.
Mini Circuits
T4–1
THS10082
49.9 Ω
R
AINP
C
C
200 Ω
R
AINM
REFOUT
Figure 43. Transformer Coupled Input
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SLAS254B – MAY 2002 – REVISED NOVEMBER 2002
MECHANICAL DATA
DA (R-PDSO-G**)
PLASTIC SMALL-OUTLINE PACKAGE
38 PINS SHOWN
0,30
0,19
M
0,13
0,65
38
20
6,20
8,40
NOM 7,80
0,15 NOM
Gage Plane
1
19
0,25
A
0°–8°
ā
0,75
0,50
Seating Plane
0,10
0,15
0,05
1,20 MAX
PINS **
28
30
32
38
DIM
9,80
9,60
11,10
10,90
11,10
10,90
12,60
12,40
A MAX
A MIN
4040066/D 11/98
NOTES:A. All linear dimensions are in millimeters.
B. This drawing is subject to change without notice.
C. Body dimensions do not include mold flash or protrusion.
D. Falls within JEDEC MO-153
34
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Copyright 2002, Texas Instruments Incorporated
相关型号:
THS1009_14
Simultaneous Sampling of Two Single-Ended Signals or One Differential Signals or Combination of Both
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