ADS8339IDGSR [TI]

16 位、250kSPS、串行接口、微功耗、迷你型 SAR ADC | DGS | 10 | -40 to 85;
ADS8339IDGSR
型号: ADS8339IDGSR
厂家: TEXAS INSTRUMENTS    TEXAS INSTRUMENTS
描述:

16 位、250kSPS、串行接口、微功耗、迷你型 SAR ADC | DGS | 10 | -40 to 85

文件: 总42页 (文件大小:2003K)
中文:  中文翻译
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ADS8339  
ZHCSCX4A JUNE 2014REVISED OCTOBER 2014  
ADS8339 16 位、250kSPS 串行接口微功耗微型  
SAR 模数转换器  
1 特性  
3 说明  
1
采样率:250kHz  
ADS8339 是一款 16 位、250kSPS 模数转换器  
(ADC)。 该器件的外部工作基准电压为 2.25V 至  
5.5V。 此器件包括一个基于电容器且具有内置采样保  
持电路的逐次逼近寄存器 (SAR) ADC。  
16 位分辨率  
全速状态下零延迟  
单极单端输入范围:  
0V Vref  
此器件还包括一个 25MHz 串行外设接口 (SPI) 兼容串  
口。 该接口设计用于支持菊花链或级联多个器件。 此  
外,忙闲指示器可轻松实现与数字主机的同步。 该器  
件的单极单端输入范围支持的输入电压摆幅为 0V 至  
Vref。  
SPI™ 兼容串口,具有菊花链选项  
使用内部时钟进行转换  
出色的性能:  
输入为 10kHz 时,信噪比 (SNR) 典型值为  
93.6dB  
该器件已经过优化,可实现低功耗运行以及根据速度直  
接调节功耗。 这一特性使得该器件对低速应用尤为实  
用。 ADS8339 采用 VSSOP-10 封装。  
输入为 10kHz 时,总谐波失真 (THD) 典型值为  
–106dB  
±2.0 最低有效位 (LSB) 最大积分非线性 (INL)  
±1.0 LSB 最大微分非线性 (DNL)  
器件信息(1)  
低功耗:  
部件号  
ADS8339  
封装  
封装尺寸(标称值)  
250kSPS 时为 17.5mW(典型值)  
VSSOP (10)  
3.00mm x 3.00mm  
功率可根据速度进行线性缩放:  
(1) 如需了解所有可用封装,请见数据表末尾的可订购产品附录。  
25kSPS 时为 1.75mW  
断电状态下的功耗:  
0.25μW(典型值)  
封装:超薄小外形尺寸封装 (VSSOP)-10  
空白  
空白  
空白  
2 应用  
电池供电类设备  
数据采集系统  
仪表和过程控制  
医用电子产品  
光纤网络  
+100 mV  
REF  
2.25 V to +VA + 0.1 V  
IN+  
2.375 V to +VA  
4.5 V to 5.5 V  
+VA  
IN+  
REFIN +VBD  
100 mV  
0 V  
SDO  
SDI  
VDIFF = (IN+) t (IN) = 0 V to REF  
NOTE: (IN+) • (IN)  
ADS8339  
SCLK  
INꢀ  
CONVST  
100 mV  
GND  
r100 mV  
INꢀ  
0 V  
Pseudo-Differential Input  
100 mV  
1
PRODUCTION DATA information is current as of publication date. Products conform to specifications per the terms of the Texas  
Instruments standard warranty. Production processing does not necessarily include testing of all parameters.  
English Data Sheet: SBAS677  
 
 
 
 
ADS8339  
ZHCSCX4A JUNE 2014REVISED OCTOBER 2014  
www.ti.com.cn  
目录  
9.1 Overview ................................................................. 16  
9.2 Functional Block Diagram ....................................... 16  
9.3 Feature Description................................................. 17  
9.4 Device Functional Modes........................................ 18  
10 Application and Implementation........................ 26  
10.1 Application Information.......................................... 26  
10.2 Typical Application ................................................ 30  
10.3 Do's and Don'ts..................................................... 31  
11 Power-Supply Recommendations ..................... 31  
12 Layout................................................................... 32  
12.1 Layout Guidelines ................................................. 32  
12.2 Layout Example .................................................... 32  
13 器件和文档支持 ..................................................... 33  
13.1 文档支持................................................................ 33  
13.2 ....................................................................... 33  
13.3 静电放电警告......................................................... 33  
13.4 术语表 ................................................................... 33  
14 机械封装和可订购信息 .......................................... 33  
1
2
3
4
5
6
7
特性.......................................................................... 1  
应用.......................................................................... 1  
说明.......................................................................... 1  
修订历史记录 ........................................................... 2  
Device Family......................................................... 3  
Pin Configuration and Functions......................... 3  
Specifications......................................................... 4  
7.1 Absolute Maximum Ratings ...................................... 4  
7.2 Handling Ratings....................................................... 4  
7.3 Recommended Operating Conditions....................... 4  
7.4 Thermal Information.................................................. 5  
7.5 Electrical Characteristics........................................... 5  
7.6 Timing Requirements................................................ 7  
7.7 Typical Characteristics.............................................. 8  
Parametric Measurement Information ............... 15  
8.1 Timing Diagrams..................................................... 15  
Detailed Description ............................................ 16  
8
9
4 修订历史记录  
Changes from Original (June 2014) to Revision A  
Page  
已更改产品预览数据表............................................................................................................................................................ 1  
2
Copyright © 2014, Texas Instruments Incorporated  
 
ADS8339  
www.ti.com.cn  
ZHCSCX4A JUNE 2014REVISED OCTOBER 2014  
5 Device Family(1)  
SAMPLING RATE  
100 kSPS  
250 kSPS  
400 kSPS  
500 kSPS  
680 kSPS  
1 MSPS  
16-BIT, SINGLE-ENDED  
ADS8866  
16-BIT, DIFFERENTIAL  
18-BIT, DIFFERENTIAL  
ADS8867  
ADS8887  
ADS8339  
ADS8864  
ADS8865  
ADS8318  
ADS8863  
ADS8861  
ADS8885  
ADS8319  
ADS8862  
ADS8883  
ADS8881  
ADS8860  
(1) All devices are pin-to-pin compatible. The ADS8339, ADS8319, and ADS8318 require a 4.5-V to 5.5-V analog supply. The remaining  
devices use a 2.7-V to 3.6-V analog supply.  
6 Pin Configuration and Functions  
DGS Package  
VSSOP-10  
(Top View)  
REFIN  
+VA  
IN+  
1
2
3
4
5
10 +VBD  
9
8
7
6
SDI  
SCLK  
SDO  
IN  
GND  
CONVST  
Pin Functions  
PIN  
FUNCTION  
DESCRIPTION  
NO.  
NAME  
Reference (positive) input. Decouple to GND with a 0.1-μF bypass capacitor and a 10-μF storage  
capacitor.  
1
REFIN  
Input  
2
3
+VA  
+IN  
Supply  
Input  
Analog power supply. Decouple with the GND pin.  
Noninverting analog signal input  
Inverting analog signal input. Note that this input has a limited range of ±0.1 V and is typically  
grounded at the input decoupling capacitor.  
4
5
6
–IN  
GND  
Input  
Supply  
Input  
Device ground. Note that this pin is a common ground pin for both the analog power supply  
(+VA) and digital I/O supply (+VBD).  
Convert input. CONVST also functions as the CS input in 3-wire interface mode. Refer to the  
Description and Timing Diagrams sections for more details.  
CONVST  
7
8
SDO  
Output  
Input  
Serial data output  
SCLK  
Serial I/O clock input. Data (on the SDO output) are synchronized with this clock.  
Serial data input. The SDI level at the start of a conversion selects the mode of operation (such  
as CS or daisy-chain mode). SDI also serves as the CS input in 4-wire interface mode. Refer to  
the Description and Timing Diagrams sections for more details.  
9
SDI  
Input  
10  
+VBD  
Supply  
Digital I/O power supply. Decouple with the GND pin.  
Copyright © 2014, Texas Instruments Incorporated  
3
ADS8339  
ZHCSCX4A JUNE 2014REVISED OCTOBER 2014  
www.ti.com.cn  
7 Specifications  
7.1 Absolute Maximum Ratings  
over operating free-air temperature range (unless otherwise noted)(1)  
MIN  
MAX  
UNIT  
V
Voltage  
–0.3  
+VA + 0.3  
+IN, –IN input  
Momentary current(2)  
130  
mA  
mA  
V
Continuous current  
±10  
+VA to GND  
–0.3  
–0.3  
–0.3  
–0.3  
–40  
7
+VBD to GND  
7
+VBD + 0.3  
+VBD + 0.3  
85  
V
Digital input voltage to GND  
Digital output voltage to GND  
V
V
Operating free-air range, TA  
Junction, TJ max  
°C  
°C  
°C  
°C/W  
°C  
Temperature  
150  
Power dissipation  
(TJmax – TA) / θJA  
121.1  
VSSOP package  
θJA thermal impedance  
Maximum VSSOP reflow temperature(3)  
260  
(1) Stresses beyond those listed under Absolute Maximum Ratings may cause permanent damage to the device. These are stress ratings  
only, which do not imply functional operation of the device at these or any other conditions beyond those indicated under Recommended  
Operating Conditions. Exposure to absolute-maximum-rated conditions for extended periods may affect device reliability.  
(2) Limit the duration for this current to less than 10 ms.  
(3) The device is rated at MSL2, 260°C, as per the JSTD-020 specification.  
7.2 Handling Ratings  
MIN  
MAX  
UNIT  
Tstg  
Storage temperature range  
–65  
150  
°C  
Human body model (HBM), per ANSI/ESDA/JEDEC JS-001, all  
pins(1)  
–1000  
–250  
1000  
250  
V(ESD)  
Electrostatic discharge  
V
Charged device model (CDM), per JEDEC specification  
JESD22-C101, all pins(2)  
(1) JEDEC document JEP155 states that 500-V HBM allows safe manufacturing with a standard ESD control process.  
(2) JEDEC document JEP157 states that 250-V CDM allows safe manufacturing with a standard ESD control process.  
7.3 Recommended Operating Conditions  
over operating free-air temperature range (unless otherwise noted)  
MIN  
4.5  
NOM  
5.0  
MAX  
UNIT  
V+VA  
V+VBD  
Vref  
Analog power-supply voltage  
Digital I/O-supply voltage  
Reference voltage  
5.5  
V
V
2.375  
2.25  
3.3  
5.5  
V+VA + 0.1  
25  
4.096  
V
f(SCLK)  
TA  
SCLK frequency  
MHz  
°C  
Operating temperature range  
–40  
85  
4
Copyright © 2014, Texas Instruments Incorporated  
ADS8339  
www.ti.com.cn  
ZHCSCX4A JUNE 2014REVISED OCTOBER 2014  
7.4 Thermal Information  
ADS8339  
THERMAL METRIC(1)  
DGS (VSSOP)  
10 PINS  
121.1  
29.4  
UNIT  
RθJA  
Junction-to-ambient thermal resistance  
RθJC(top)  
RθJB  
Junction-to-case (top) thermal resistance  
Junction-to-board thermal resistance  
32.0  
°C/W  
ψJT  
Junction-to-top characterization parameter  
Junction-to-board characterization parameter  
Junction-to-case (bottom) thermal resistance  
0.7  
ψJB  
31.5  
RθJC(bot)  
N/A  
(1) For more information about traditional and new thermal metrics, see the IC Package Thermal Metrics application report, SPRA953.  
7.5 Electrical Characteristics  
All minimum and maximum specifications are at TA = –40°C to 85°C, +VA = 5 V, +VBD = 5 V to 2.375 V, Vref = 4 V, and fsample  
= 250 kHz, unless otherwise noted. Typical specifications are at TA = 25°C.  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
ANALOG INPUT  
Full-scale input span(1)  
+IN – (–IN)  
+IN  
0
–0.1  
–0.1  
Vref  
Vref + 0.1  
0.1  
V
V
Operating input range  
–IN  
V
Ci  
Input capacitance  
59  
pF  
pA  
Input leakage current  
During acquisition  
1000  
SYSTEM PERFORMANCE  
Resolution  
16  
Bits  
Bits  
LSB(3)  
NMC  
INL  
DNL  
EO  
No missing codes  
Integral linearity(2)  
Differential linearity  
Offset error(4)  
16  
–2.0  
±1.2  
±0.65  
2.0  
1.0  
At 16-bit level  
–0.99  
–1.5  
LSB  
±0.3  
1.5  
mV  
EG  
Gain error  
–0.03  
±0.0045  
0.03  
%FSR  
With common-mode input signal = 200 mVPP  
at 250 kHz  
CMRR  
PSRR  
Common-mode rejection ratio  
78  
dB  
Power-supply rejection ratio  
Transition noise  
At FFF0h output code  
80  
dB  
0.5  
LSB  
SAMPLING DYNAMICS  
tcnv Conversion time  
tacq  
500(5)  
700  
3300  
0.25  
ns  
ns  
Acquisition time  
Maximum throughput rate  
with or without latency  
MHz  
Aperture delay  
2.5  
6
ns  
ps  
ns  
ns  
Aperture jitter, RMS  
Step response  
Settling to 16-bit accuracy  
Settling to 16-bit accuracy  
600  
600  
Overvoltage recovery  
(1) Ideal input span, does not include gain or offset error.  
(2) This parameter is the endpoint INL, not best-fit INL.  
(3) LSB = least significant bit.  
(4) Measured relative to actual measured reference.  
(5) Refer to the CS Mode for a 3-Wire Interface section in the Device Functional Modes.  
Copyright © 2014, Texas Instruments Incorporated  
5
ADS8339  
ZHCSCX4A JUNE 2014REVISED OCTOBER 2014  
www.ti.com.cn  
Electrical Characteristics (continued)  
All minimum and maximum specifications are at TA = –40°C to 85°C, +VA = 5 V, +VBD = 5 V to 2.375 V, Vref = 4 V, and fsample  
= 250 kHz, unless otherwise noted. Typical specifications are at TA = 25°C.  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
DYNAMIC CHARACTERISTICS  
VIN = 0.4 dB below fS at 1 kHz, Vref = 5 V  
VIN = 0.4 dB below fS at 10 kHz, Vref = 5 V  
VIN = 0.4 dB below fS at 1 kHz, Vref = 5 V  
VIN = 0.4 dB below fS at 10 kHz, Vref = 5 V  
VIN = 0.4 dB below fS at 1 kHz, Vref = 5 V  
VIN = 0.4 dB below fS at 10 kHz, Vref = 5 V  
VIN = 0.4 dB below fS at 1 kHz, Vref = 5 V  
VIN = 0.4 dB below fS at 10 kHz, Vref = 5 V  
–111  
–106  
93.9  
93.6  
93.8  
93.4  
113  
dB  
dB  
THD  
Total harmonic distortion(6)  
Signal-to-noise ratio  
dB  
SNR  
dB  
dB  
SINAD  
SFDR  
Signal-to-noise + distortion  
dB  
dB  
Spurious-free dynamic range  
–3-dB small-signal bandwidth  
107  
dB  
15  
MHz  
EXTERNAL REFERENCE INPUT  
Vref  
Input range  
Reference input current(7)  
2.25  
4.096  
75  
VA + 0.1  
V
During conversion  
μA  
POWER-SUPPLY REQUIREMENTS  
+VBD  
+VA  
2.375  
4.5  
3.3  
5
5.5  
5.5  
V
V
Power-supply voltage  
ICC  
Supply current  
+VA  
250-kHz sample rate  
+VA = 5 V, 250-kHz sample rate  
+VA = 5 V  
3.5  
17.5  
50  
4.0  
mA  
mW  
nA  
PVA  
IVApd  
Power dissipation  
Device power-down current(8)  
20.0  
300  
LOGIC FAMILY CMOS  
VIH  
VIL  
High-level input voltage  
IIH = 5 μA  
0.7 × VBD  
–0.3  
VBD + 0.3  
0.3 × VBD  
VBD  
V
V
V
V
Low-level input voltage  
High-level output voltage  
Low-level output voltage  
IIL = 5 μA  
VOH  
VOL  
IOH = 2 TTL loads  
IOL = 2 TTL loads  
VBD – 0.3  
0
0.4  
TEMPERATURE RANGE  
TA Operating free-air temperature  
–40  
85  
°C  
(6) Calculated on the first nine harmonics of the input frequency.  
(7) Can vary by ±20%.  
(8) The device automatically enters a power-down state at the end of every conversion and remains in a power-down state as long as the  
device is in an acquisition phase.  
6
Copyright © 2014, Texas Instruments Incorporated  
ADS8339  
www.ti.com.cn  
ZHCSCX4A JUNE 2014REVISED OCTOBER 2014  
7.6 Timing Requirements  
All specifications are at TA = –40°C to 85°C, +VA = 5 V, and 5.5 V > +VBD 2.375 V, unless otherwise noted.  
PARAMETER  
TEST CONDITIONS  
MIN  
TYP  
MAX  
UNIT  
SAMPLING AND CONVERSION  
Acquisition time  
(see Figure 47, Figure 49, Figure 50, Figure 53)  
tacq  
tcnv  
tcyc  
t1  
700  
ns  
ns  
Conversion time  
(see Figure 47, Figure 49, Figure 50, Figure 53)  
500(1)  
3300  
Time between conversions  
(see Figure 47, Figure 49, Figure 50, Figure 53)  
4000  
10  
ns  
ns  
ns  
Pulse duration, CONVST high (see Figure 47, Figure 49)  
Pulse duration, CONVST low  
(see Figure 50, Figure 53, Figure 55)  
t6  
20  
INPUTS AND OUTPUTS (I/O)  
SCLK period (see Figure 47, Figure 49, Figure 50, Figure 53,  
Figure 55, Figure 57)  
tclk  
tclkl  
tclkh  
t2  
40.0  
0.45  
0.45  
5
ns  
tclk  
tclk  
ns  
SCLK low time (see Figure 47, Figure 49, Figure 50, Figure 53,  
Figure 55, Figure 57)  
0.55  
0.55  
SCLK high time (see Figure 47, Figure 49, Figure 50, Figure 53,  
Figure 55, Figure 57)  
SCLK falling edge to data remains valid (see Figure 47, Figure 49,  
Figure 50, Figure 53, Figure 55, Figure 57)  
5.5 V +VBD 4.5 V  
16  
24  
15  
22  
12  
ns  
ns  
ns  
ns  
ns  
SCLK falling edge to next data valid delay (see Figure 47,  
Figure 49, Figure 50, Figure 53, Figure 55, Figure 57)  
t3  
4.5 V > +VBD 2.375 V  
5.5 V +VBD 4.5 V  
4.5 V > +VBD 2.375 V  
5.5 V +VBD 4.5 V  
CONVST or SDI low to MSB valid  
(see Figure 47, Figure 50)  
ten  
CONVST or SDI high or last SCLK falling edge to SDO  
3-state (CS mode)  
(see Figure 47, Figure 49, Figure 50, Figure 53)  
tdis  
4.5 V > +VBD 2.375 V  
15  
ns  
ns  
SDI valid setup time to CONVST rising edge  
(see Figure 50, Figure 53)  
t4  
t5  
t7  
t8  
5
5
5
5
SDI valid hold time from CONVST rising edge  
(see Figure 50, Figure 53)  
ns  
ns  
ns  
SCLK valid setup time to CONVST rising edge  
(see Figure 55)  
SCLK valid hold time from CONVST rising edge  
(see Figure 55)  
(1) Refer to the CS Mode for a 3-Wire Interface subsection in the Device Functional Modes section.  
Copyright © 2014, Texas Instruments Incorporated  
7
 
ADS8339  
ZHCSCX4A JUNE 2014REVISED OCTOBER 2014  
www.ti.com.cn  
7.7 Typical Characteristics  
At TA = 30°C, +VA = 5 V, +VBD = 2.7 V, Vref = 4.096 V, and fsample = 250 kHz, unless otherwise noted.  
±0.2  
±0.25  
±0.3  
0.005  
0.0045  
0.004  
0.0035  
0.003  
0.0025  
0.002  
0.0015  
0.001  
0.0005  
0
±0.35  
±0.4  
±0.45  
±0.5  
4.5  
4.75  
5
5.25  
5.5  
4.5  
4.75  
5
5.25  
5.5  
Supply Voltage (V)  
Supply Voltage (V)  
C001  
C002  
+VBD = 2.7 V, Vref = 4.096 V, fS = 250 kSPS, TA = 30°C  
+VBD = 2.7 V, Vref = 4.096 V, fS = 250 kSPS, TA = 30°C  
Figure 1. Offset Error vs Supply Voltage  
Figure 2. Gain Error vs Supply Voltage  
0
0.0045  
0.004  
0.0035  
0.003  
0.0025  
0.002  
0.0015  
0.001  
0.0005  
0
±0.05  
±0.1  
±0.15  
±0.2  
±0.25  
±0.3  
±0.35  
2
2.5  
3
3.5  
4
4.5  
5
2
2.5  
3
3.5  
4
4.5  
5
Reference Voltage (V)  
Reference Voltage (V)  
C003  
C004  
+VBD = 2.7 V, +VA = 5 V, fS = 250 kSPS, TA = 30°C  
+VBD = 2.7 V, +VA = 5 V, fS = 250 kSPS, TA = 30°C  
Figure 3. Offset Error vs Reference Voltage  
Figure 4. Gain Error vs Reference Voltage  
0
±0.1  
±0.2  
±0.3  
±0.4  
±0.5  
±0.6  
±0.7  
±0.8  
±0.9  
±1  
0.01  
0.009  
0.008  
0.007  
0.006  
0.005  
0.004  
0.003  
0.002  
0.001  
0
0
20  
40  
60  
80  
100  
0
20  
40  
60  
80  
100  
±40  
±20  
±40  
±20  
Free-Air Temperature (ƒC)  
Free-Air Temperature (ƒC)  
C005  
C006  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fS = 250 kSPS  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fS = 250 kSPS  
Figure 5. Offset Error vs Free-Air Temperature  
Figure 6. Gain Error vs Free-Air Temperature  
8
Copyright © 2014, Texas Instruments Incorporated  
ADS8339  
www.ti.com.cn  
ZHCSCX4A JUNE 2014REVISED OCTOBER 2014  
Typical Characteristics (continued)  
At TA = 30°C, +VA = 5 V, +VBD = 2.7 V, Vref = 4.096 V, and fsample = 250 kHz, unless otherwise noted.  
14  
12  
10  
8
25  
20  
15  
10  
5
12  
12  
20  
6
4
3
3
5
5
2
1
1
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
ppm/ƒC  
ppm/ƒC  
C007  
C008  
+VBD = 2.7 V, +VA = 5 V, fS = 250 kSPS  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fS = 250 kSPS  
Figure 7. Gain Error Drift Histogram  
Figure 8. Offset Error Drift Histogram  
1
1.5  
INL Max  
DNL Max  
DNL Min  
0.8  
0.6  
0.4  
0.2  
INL Min  
1
0.5  
0
0
±0.2  
±0.4  
±0.6  
±0.8  
±1  
±0.5  
±1  
±1.5  
4.5  
4.75  
5
5.25  
5.5  
4.5  
4.75  
5
5.25  
5.5  
Supply Voltage (V)  
Supply Voltage (V)  
C009  
C010  
+VBD = 2.7 V, Vref = 4.096 V, fS = 250 kSPS, TA = 30°C  
+VBD = 2.7 V, Vref = 4.096 V, fS = 250 kSPS, TA = 30°C  
Figure 9. DNL vs Supply Voltage  
Figure 10. INL vs Supply Voltage  
1
1.5  
INL Max  
DNL Max  
DNL Min  
0.8  
0.6  
0.4  
0.2  
DNL Min  
1
1
0.5  
0
0
±0.2  
±0.4  
±0.6  
±0.8  
±1  
±0.5  
±1  
±1.5  
2
2.5  
3
3.5  
4
4.5  
5
2
2.5  
3
3.5  
4
4.5  
5
Reference Voltage (V)  
Reference Voltage (V)  
C011  
C012  
+VBD = 2.7 V, +VA = 5 V, fS = 250 kSPS, TA = 30°C  
+VBD = 2.7 V, +VA = 5 V, fS = 250 kSPS, TA = 30°C  
Figure 11. DNL vs Reference Voltage  
Figure 12. INL vs Reference Voltage  
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Typical Characteristics (continued)  
At TA = 30°C, +VA = 5 V, +VBD = 2.7 V, Vref = 4.096 V, and fsample = 250 kHz, unless otherwise noted.  
1
1
DNL Max  
DNL Min  
0.8  
0.6  
0.4  
0.2  
0.8  
0.6  
0.4  
0.2  
INL Max  
INL Min  
0
0
±0.2  
±0.4  
±0.6  
±0.8  
±1  
±0.2  
±0.4  
±0.6  
±0.8  
±1  
0
20  
40  
60  
80  
100  
0
20  
40  
60  
80  
100  
±40  
±20  
±40  
±20  
Free-Air Temperature (ƒC)  
Free-Air Temperature (ƒC)  
C013  
C014  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fS = 250 kSPS  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fS = 250 kSPS  
Figure 13. DNL vs Free-Air Temperature  
Figure 14. INL vs Free-Air Temperature  
16  
16  
15.9  
15.8  
15.8  
15.7  
15.6  
15.5  
15.4  
15.3  
15.2  
15.1  
15  
15.6  
15.4  
15.2  
15  
14.8  
14.6  
14.4  
14.2  
14  
4.5  
4.75  
5
5.25  
5.5  
2
2.5  
3
3.5  
4
4.5  
5
Supply Voltage (V)  
Reference Voltage (V)  
C015  
C016  
+VBD = 2.7 V, Vref = 5 V, fIN = 1.9 kHz, fS = 250 kSPS,  
TA = 30°C  
+VBD = 2.7 V, +VA = 5 V, fIN = 1.9 kHz, fS = 250 kSPS, TA = 30°C  
Figure 15. ENOB vs Supply Voltage  
Figure 16. ENOB vs Reference Voltage  
16  
15.9  
15.8  
15.7  
15.6  
15.5  
15.4  
15.3  
15.2  
15.1  
15  
119  
117  
115  
113  
111  
109  
107  
105  
0
20  
40  
60  
80  
100  
4.5  
4.75  
5
5.25  
5.5  
±40  
±20  
Free-Air Temperature (ƒC)  
Supply Voltage (V)  
C017  
C018  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fIN = 1.9 kHz,  
fS = 250 kSPS  
+VBD = 2.7 V, Vref = 4.096 V, fIN = 1.9 kHz, fS = 250 kSPS,  
TA = 30°C  
Figure 17. ENOB vs Free-Air Temperature  
Figure 18. SFDR vs Supply Voltage  
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Typical Characteristics (continued)  
At TA = 30°C, +VA = 5 V, +VBD = 2.7 V, Vref = 4.096 V, and fsample = 250 kHz, unless otherwise noted.  
94.5  
94.5  
94  
94  
93.5  
93  
93.5  
93  
92.5  
92  
92.5  
92  
4.5  
4.75  
5
5.25  
5.5  
4.5  
4.75  
5
5.25  
5.5  
Supply Voltage (V)  
Supply Voltage (V)  
C019  
C020  
+VBD = 2.7 V, Vref = 4.096 V, fIN = 1.9 kHz, fS = 250 kSPS,  
TA = 30°C  
+VBD = 2.7 V, Vref = 4.096 V, fIN = 1.9 kHz, fS = 250 kSPS,  
TA = 30°C  
Figure 19. SINAD vs Supply Voltage  
Figure 20. SNR vs Supply Voltage  
119  
119  
117  
115  
113  
111  
109  
107  
105  
117  
115  
113  
111  
109  
107  
105  
4.5  
4.75  
5
5.25  
5.5  
2
2.5  
3
3.5  
4
4.5  
5
Supply Voltage (V)  
Reference Voltage (V)  
C021  
C022  
+VBD = 2.7 V, Vref = 4.096 V, fIN = 1.9 kHz, fS = 250 kSPS,  
TA = 30°C  
+VBD = 2.7 V, +VA = 5 V, fIN = 1.9 kHz, fS = 250 kSPS, TA = 30°C  
Figure 21. THD vs Supply Voltage  
Figure 22. SFDR vs Reference Voltage  
95  
94.5  
94  
95  
94.5  
94  
93.5  
93  
93.5  
93  
92.5  
92  
92.5  
92  
91.5  
91  
91.5  
91  
90.5  
90  
90.5  
90  
2
2.5  
3
3.5  
4
4.5  
5
2
2.5  
3
3.5  
4
4.5  
5
Reference Voltage (V)  
Reference Voltage (V)  
C023  
C024  
+VBD = 2.7 V, +VA = 5 V, fIN = 1.9 kHz, fS = 250 kSPS, TA = 30°C  
+VBD = 2.7 V, +VA = 5 V, fIN = 1.9 kHz, fS = 250 kSPS, TA = 30°C  
Figure 23. SINAD vs Reference Voltage  
Figure 24. SNR vs Reference Voltage  
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Typical Characteristics (continued)  
At TA = 30°C, +VA = 5 V, +VBD = 2.7 V, Vref = 4.096 V, and fsample = 250 kHz, unless otherwise noted.  
119  
117  
115  
113  
111  
109  
107  
105  
119  
117  
115  
113  
111  
109  
107  
105  
103  
2
2.5  
3
3.5  
4
4.5  
5
0
20  
40  
60  
80  
100  
±40  
±20  
Reference Voltage (V)  
Free-Air Temperature (ƒC)  
C025  
C026  
+VBD = 2.7 V, +VA = 5 V, fIN = 1.9 kHz, fS = 250 kSPS, TA = 30°C  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fIN = 1.9 kHz,  
fS = 250 kSPS  
Figure 26. SFDR vs Free-Air Temperature  
Figure 25. THD vs Reference Voltage  
96  
96  
95  
94  
93  
92  
91  
90  
95  
94  
93  
92  
91  
90  
0
20  
40  
60  
80  
100  
0
20  
40  
60  
80  
100  
±40  
±20  
±40  
±20  
Free-Air Temperature (ƒC)  
Free-Air Temperature (ƒC)  
C027  
C028  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fIN = 1.9 kHz,  
fS = 250 kSPS  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fIN = 1.9 kHz,  
fS = 250 kSPS  
Figure 27. SINAD vs Free-Air Temperature  
Figure 28. SNR vs Free-Air Temperature  
117  
95  
SINAD at ±10 dB  
94  
93  
92  
91  
90  
89  
88  
87  
SINAD at ±0.5 dB  
115  
113  
111  
109  
107  
105  
103  
0
20  
40  
60  
80  
100  
1
10  
100  
±40  
±20  
Free-Air Temperature (ƒC)  
Signal Input Frequency (kHz)  
C029  
C030  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fIN = 1.9 kHz,  
fS = 250 kSPS  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fS = 250 kSPS, TA = 30°C  
Figure 29. THD vs Free-Air Temperature  
Figure 30. SINAD vs Signal Input Frequency  
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Typical Characteristics (continued)  
At TA = 30°C, +VA = 5 V, +VBD = 2.7 V, Vref = 4.096 V, and fsample = 250 kHz, unless otherwise noted.  
135  
125  
115  
105  
95  
300000  
250000  
200000  
150000  
100000  
50000  
0
THD at ±10 dB  
THD at ±0.5 dB  
262043  
85  
101  
0
75  
1
10  
Signal Input Frequency (kHz)  
100  
C031  
Codes  
C032  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fS = 250 kSPS, TA = 30°C  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fS = 250 kSPS, TA = 30°C  
Figure 32. DC Histogram of ADC Close-to-Center Code  
Figure 31. THD vs Signal Input Frequency  
114  
3.5  
0 pF  
100 pF  
680 pF  
112  
3.45  
3.4  
110  
108  
106  
104  
102  
100  
3.35  
3.3  
3.25  
3.2  
0
100  
200  
300  
400  
500  
600  
4.5  
4.75  
5
5.25  
5.5  
Source Resistance (  
Supply Voltage (V)  
C033  
C034  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fIN = 1.9 kHz,  
fS = 250 kSPS, TA = 30°C  
+VBD = 2.7 V, Vref = 4.096 V, fS = 250 kSPS, TA = 30°C  
Figure 33. THD vs Source Resistance  
Figure 34. Supply Current vs Supply Voltage  
3.8  
3.7  
3.6  
3.5  
3.4  
3.3  
3.2  
3.1  
3.0  
2.9  
2.8  
4
3.5  
3
2.5  
2
1.5  
1
0.5  
0
0
20  
40  
60  
80  
100  
0
50  
100  
150  
200  
250  
±40  
±20  
Free-Air Temperature (ƒC)  
Sampling Frequency (kSPS)  
C035  
C036  
+VBD = 2.7 V, +VA = 5 V, fS = 250 kSPS  
Figure 35. Supply Current vs Free-Air Temperature  
+VBD = 2.7 V, +VA = 5 V, TA = 30°C  
Figure 36. Supply Current vs Sampling Frequency  
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Typical Characteristics (continued)  
At TA = 30°C, +VA = 5 V, +VBD = 2.7 V, Vref = 4.096 V, and fsample = 250 kHz, unless otherwise noted.  
20  
18  
16  
14  
12  
10  
8
15  
14  
13  
12  
11  
10  
9
6
8
4
7
2
6
0
5
0
50  
100  
150  
200  
250  
4.5  
4.75  
5
5.25  
5.5  
Sampling Frequency (kSPS)  
Supply Voltage (V)  
C037  
C038  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, TA = 30°C  
+VBD = 2.7 V, Vref = 4.096 V, fS = 250 kSPS, TA = 30°C  
Figure 37. Power Dissipation vs Sampling Frequency  
Figure 38. Power-Down Current vs Supply Voltage  
60  
1
0.8  
0.6  
0.4  
0.2  
50  
40  
30  
20  
10  
0
0
±0.2  
±0.4  
±0.6  
±0.8  
±1  
0
20  
40  
60  
80  
100  
0
10000 20000 30000 40000 50000 60000  
Codes  
±40  
±20  
Free-Air Temperature (ƒC)  
C039  
C040  
+VBD = 2.7 V, +VA = 5 V, Vref = 4.096 V, fS = 250 kSPS  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fS = 250 kSPS, TA = 30°C  
Figure 39. Power-Down Current vs Free-Air Temperature  
Figure 40. DNL Error vs Output Code  
1
0
±20  
0.8  
0.6  
0.4  
0.2  
±40  
±60  
±80  
0
±100  
±120  
±140  
±160  
±180  
±200  
±0.2  
±0.4  
±0.6  
±0.8  
±1  
0
10000 20000 30000 40000 50000 60000  
Codes  
0
50000  
100000  
150000  
200000  
250000  
Frequency (Hz)  
C041  
C042  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fS = 250 kSPS, TA = 30°C  
+VBD = 2.7 V, +VA = 5 V, Vref = 5 V, fIN = 1.9 kHz,  
fS = 250 kSPS, TA = 30°C  
Figure 42. Signal Strength vs Frequency  
Figure 41. INL Error vs Output Code  
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8 Parametric Measurement Information  
8.1 Timing Diagrams  
IOL  
500 mA  
From SDO  
20 pF  
1.4 V  
IOH  
500 mA  
Figure 43. Digital Interface Timing Load Circuit  
0.7 VBD  
0.3 VBD  
tDELAY  
tDELAY  
2 V  
2 V  
0.8 V  
0.8 V  
Figure 44. Timing Voltage Levels  
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9 Detailed Description  
9.1 Overview  
The ADS8339 is a 250-kSPS, low-power, successive-approximation register (SAR), analog-to-digital converter  
(ADC) that uses an external reference. The architecture is based on charge redistribution, which inherently  
includes a sample-and-hold function.  
The ADS8339 is a single-channel device. The analog input is provided to two input pins: +IN and –IN, where –IN  
is a pseudo-differential input and has a limited range of ±0.1 V. When a conversion is initiated, the differential  
input on these pins is sampled on the internal capacitor array. While a conversion is in progress, both the +IN  
and –IN inputs are disconnected from any internal functions.  
The device has an internal clock that is used to run the conversion. Therefore, the conversion requires a fixed  
amount of time. After a conversion is completed, the device reconnects the sampling capacitors to the +IN and  
–IN pins and the device is in the acquisition phase. During this phase, the device is powered down and  
conversion data can be read.  
The device digital output is available in SPI-compatible format. The device easily interfaces with  
microprocessors, digital signal processors (DSPs), or field-programmable gate arrays (FPGAs).  
9.2 Functional Block Diagram  
+VA  
+VBD  
Output  
Drive  
SAR  
SDO  
Comparator  
IN+  
Input  
Shift  
Register  
SDI  
CDAC  
IN-  
REFIN  
Conversion and I/O  
Control Logic  
SCLK  
Device  
GND  
CONVST  
16  
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9.3 Feature Description  
9.3.1 Analog Input  
When the converter samples the input, the voltage difference between the +IN and –IN inputs is captured on the  
internal capacitor array. The differential signal range is [(+IN) – (–IN)]. The voltage on +IN is limited between  
GND – 0.1 V and Vref + 0.1 V and the voltage on –IN is limited between GND – 0.1 V to GND + 0.1 V. The input  
rejects any small signal that is common to both the +IN and –IN input.  
The (peak) input current through the analog input depends upon a number of factors: sample rate, input voltage,  
and source impedance. The current into the device charges the internal capacitor array (as shown in Figure 45)  
during the sample period. When this capacitance is fully charged, there is no further input current. The source of  
the analog input voltage must be able to charge the input capacitance (59 pF) to a 18-bit settling level within the  
minimum acquisition time. When the converter goes into hold mode, the input impedance is greater than 1 G.  
Care must be taken regarding the absolute analog input voltage. To maintain linearity of the converter, the +IN  
input, –IN input, and span [+IN – (–IN)] must be within the limits specified. Outside of these ranges, the converter  
linearity may not meet specifications.  
Care must also be taken to ensure that the output impedance of the sources driving the +IN input and the –IN  
input is matched. If this output impedance is not well matched, the two inputs can have different settling times.  
This mismatch may result in an offset error, gain error, and linearity error that changes with temperature and  
input voltage. Typically, the –IN input is grounded at the input decoupling capacitor.  
Device in Hold Mode  
55 pF  
218 W  
+IN  
4 pF  
4 pF  
+VA  
AGND  
55 pF  
218 W  
-IN  
Figure 45. Input Equivalent Circuit  
9.3.2 Power Saving  
The device has an auto power-down feature. The device powers down at the end of every conversion. The input  
signal is acquired on sampling capacitors when the device is in power-down state. At the same time, the  
conversion results are available for reading. The device powers up automatically at the start of the conversion.  
The conversion runs on an internal clock and requires a fixed time. As a result, device power consumption is  
directly proportional to the speed of operation.  
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Feature Description (continued)  
9.3.3 Digital Output  
As discussed in the Description and Timing Diagrams sections, the device digital output is SPI-compatible.  
Table 1 lists the output codes corresponding to various analog input voltages.  
Table 1. Output Codes  
DESCRIPTION  
ANALOG VALUE (V)  
DIGITAL OUTPUT STRAIGHT BINARY  
BINARY CODE HEX CODE  
Full-scale range  
Vref  
Vref / 65536  
+Vref – 1 LSB  
Vref / 2  
Least significant bit (LSB)  
Positive full-scale  
Mid-scale  
1111 1111 1111 1111  
1000 0000 0000 0000  
0111 1111 1111 1111  
0000 0000 0000 0000  
FFFF  
8000  
7FFF  
0000  
Mid-scale – 1 LSB  
Zero  
Vref / 2 – 1 LSB  
0
9.3.4 SCLK Input  
The device uses SCLK for the serial data output. Data are read after the conversion is complete and the device  
is in acquisition phase. A free-running SCLK can be used, but TI recommends stopping the clock during  
conversion time because the clock edges can couple with the internal analog circuit that, in turn, can affect the  
conversion results.  
9.4 Device Functional Modes  
The ADS8339 supports three interface options. Under each option, the device can be used with or without a  
busy indicator.  
1. CS mode for a 3-wire interface (with or without a busy indicator): This mode is useful for applications where  
a single ADS8339 device is connected to the digital host.  
2. CS mode for a 4-wire interface (with or without a busy indicator): This mode can be used when more than  
one ADS8339 device is connected to the digital host on a common data bus.  
3. Daisy-chain mode (with or without a busy indicator): This mode is provided to connect multiple ADS8339  
devices in a chain (such as a shift register) and is useful when reducing the number of signal traces on the  
board or the component count.  
The busy indicator is generated as the bit preceding the 16-bit serial data.  
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Device Functional Modes (continued)  
9.4.1 CS Mode for a 3-Wire Interface  
CS mode is selected if SDI is high at the CONVST rising edge. As previously indicated, the device can be used  
without or with a busy indicator. This section discusses this interface and the two options in detail.  
9.4.1.1 3-Wire CS Mode Without a Busy Indicator  
In a 3-wire CS mode, SDI is permanently tied to +VBD, as shown in Figure 46. CONVST functions like CS. As  
shown in Figure 47, the device samples the input signal and enters the conversion phase on the CONVST rising  
edge. SDO goes to 3-state at the same time. Conversion is done with the internal clock and continues regardless  
of the state of CONVST. As a result, CONVST (functioning as CS) can be brought low after the start of the  
conversion to select other devices on the board.  
CONVST must return to high before the minimum conversion time (tcnv_min in the Timing Requirements table)  
elapses. A high level on CONVST at the end of the conversion ensures the device does not generate a busy  
indicator.  
Digital Host  
Device  
CNV  
CONVST  
+VBD  
CLK  
SDI  
SDI  
SCLK  
SDO  
Figure 46. Connection Diagram: 3-Wire CS Mode without a Busy Indicator (SDI = 1)  
tcyc  
t1  
CONVST  
tcnv_min  
tcnv  
tacq  
Acquisition  
Acquisition  
Phase  
SCLK  
Conversion  
tclkl  
t2  
1
2
16  
15  
tclkh  
ten  
tdis  
t3  
D14  
tclk  
D15  
D0  
SDO  
D1  
Figure 47. Interface Timing Diagram: 3-Wire CS Mode Without a Busy Indicator (SDI = 1)  
When the conversion is complete, the device enters acquisition phase and powers down. On the CONVST falling  
edge, SDO comes out of 3-state and the device outputs the MSB of the data. Afterwards, the device outputs the  
next lower data bits on every subsequent SCLK falling edge. A minimum of 15 SCLK falling edges must occur  
during the low period of CONVST. SDO goes to 3-state after the 16th SCLK falling edge or when CONVST is  
high, whichever occurs first.  
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Device Functional Modes (continued)  
9.4.1.2 3-Wire CS Mode With a Busy Indicator  
As stated in the 3-Wire CS Mode Without a Busy Indicator section, SDI is permanently tied to +VBD, as shown in  
Figure 48. CONVST functions like CS. As shown in Figure 49, the device samples the input signal and enters the  
conversion phase on the CONVST rising edge. SDO goes to 3-state at the same time. Conversion is done with  
the internal clock and continues regardless of the state of CONVST. As a result, CONVST (functioning as CS)  
can be toggled after the start of the conversion to select other devices on the board.  
CONVST must return to low before the minimum conversion time (tcnv_min in the Timing Requirements table)  
elapses and remains low until the end of the maximum conversion time. A low level on the CONVST input at the  
end of a conversion ensures the device generates a busy indicator (low level on SDO). For fast settling, a 10-kΩ  
pull-up resistor tied to +VBD is recommended to provide the necessary current to drive SDO low.  
Digital Host  
Device  
CNV  
CLK  
CONVST  
+VBD  
SDI  
SCLK  
SDO  
+VBD  
SDI  
IRQ  
Figure 48. Connection Diagram: 3-Wire CS Mode With a Busy Indicator  
tcyc  
t1  
CONVST  
tcnv_min  
tacq  
Acquisition  
tcnv  
Acquisition  
Conversion  
Phase  
SCLK  
t2  
tclkl  
1
17  
2
3
16  
tclkh  
t3  
D14  
tdis  
tclk  
D15  
D0  
SDO  
D1  
Figure 49. Interface Timing Diagram: 3-Wire CS Mode With a Busy Indicator (SDI = 1)  
When the conversion is complete, the device enters acquisition phase, powers down, forces SDO out of 3-state,  
and outputs a busy indicator bit (low level). The device outputs the MSB of data on the first SCLK falling edge  
after the conversion is complete and continues to output the next lower data bits on every subsequent SCLK  
falling edge. A minimum of 16 SCLK falling edges must occur during the low period of CONVST. SDO goes to 3-  
state after the 17th SCLK falling edge or when CONVST is high, whichever occurs first.  
20  
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Device Functional Modes (continued)  
9.4.2 CS Mode for a 4-Wire Interface  
This interface is similar to the CS mode for 3-wire interface except that SDI is controlled by the digital host. This  
section discusses in detail the interface option with and without a busy indicator.  
9.4.2.1 4-Wire CS Mode Without a Busy Indicator  
As mentioned previously, in order to select CS mode, SDI must be high at the time of the CONVST rising edge.  
Unlike in the 3-wire interface option, SDI is controlled by the digital host and functions like CS. As shown in  
Figure 50, SDI goes to a high level before the CONVST rising edge. When SDI is high, the CONVST rising edge  
selects CS mode, forces SDO to 3-state, samples the input signal, and the device enters the conversion phase.  
In the 4-wire interface option, CONVST must be at a high level from the start of the conversion until all data bits  
are read. Conversion is done with the internal clock and continues regardless of the state of SDI. As a result, SDI  
(functioning as CS) can be brought low to select other devices on the board.  
SDI must return to high before the minimum conversion time (tcnv_min in the Timing Requirements table) elapses.  
t
CONVST  
6
SDI (CS) 1  
t
4
t
5
SDI (CS) 2  
tcnv_min  
t
t
acq  
cnv  
t
en  
Acquisition  
Phase  
SCLK  
Conversion  
Acquisition  
t
t
clkl  
2
17  
1
2
t
16  
31  
32  
15  
18  
t
t
dis  
clkh  
t
t
dis  
en  
t
clk  
3
D15 #1 D14 #1  
D1 #1  
D0 #1  
D15 #2 D14 #2  
D1 #2  
D0 #2  
SDO  
Figure 50. Interface Timing Diagram: 4-Wire CS Mode Without a Busy Indicator  
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Device Functional Modes (continued)  
When the conversion is complete, the device enters the acquisition phase and powers down. An SDI falling edge  
can occur after the maximum conversion time (tcnv in the Timing Requirements table). Note that SDI must be high  
at the end of the conversion so that the device does not generate a busy indicator. The SDI falling edge brings  
SDO out of 3-state and the device outputs the MSB of the data. Subsequently, the device outputs the next lower  
data bits on every subsequent SCLK falling edge. SDO goes to 3-state after the 16th SCLK falling edge or when  
SDI (CS) is high, whichever occurs first. As shown in Figure 51, multiple devices can be chained on the same  
data bus. In this case, the second device SDI (functioning as CS) can go low after the first device data are read  
and the device 1 SDO is in 3-state.  
Care must be taken so that CONVST and SDI are not both low at any time during the cycle.  
CS1  
CS2  
CNV  
CONVST  
SDI  
CONVST  
SDI  
SDO  
SDO  
SDI  
SCLK  
SCLK  
CLK  
Device 2  
Device 1  
Digital Host  
Figure 51. Connection Diagram: 4-Wire CS Mode Without a Busy Indicator  
9.4.2.2 4-Wire CS Mode With a Busy Indicator  
As mentioned previously, in order to select CS mode, SDI must be high at the time of the CONVST rising edge.  
In this mode of operation, the connection is made as shown in Figure 52.  
CS  
SDI  
CONVST  
SCLK  
CNV  
CLK  
+VBD  
SDO  
SDI  
IRQ  
Device  
Digital Host  
Figure 52. Connection Diagram: 4-Wire CS Mode With a Busy Indicator  
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Device Functional Modes (continued)  
Unlike in the 3-wire interface option, SDI is controlled by the digital host and functions like CS. As shown in  
Figure 53, SDI goes to a high level before the CONVST rising edge. When SDI is high, the CONVST rising edge  
selects the CS mode, forces SDO to 3-state, samples the input signal, and the device enters the conversion  
phase.  
In the 4-wire interface option, CONVST must be at a high level from the start of the conversion until all data bits  
are read. Conversion is done with the internal clock and continues regardless of the state of SDI. As a result, SDI  
(functioning as CS) can be toggled to select other devices on the board.  
SDI must return low before the minimum conversion time (tcnv_min in the Timing Requirements table) elapses and  
must remain low until the end of the maximum conversion time. A low level on the SDI input at the end of a  
conversion ensures the device generates a busy indicator (low on SDO). For fast settling, a 10-kΩ pull-up  
resistor tied to +VBD is recommended to provide the necessary current to drive SDO low.  
tcyc  
t6  
CNVST  
t5  
SDI ( CS )  
t4  
tcnv_min  
tacq  
tcnv  
Acquisition  
Phase  
SCLK  
SDO  
Conversion  
Acquisition  
t2  
tclkh  
1
17  
2
3
16  
tclkl  
t3  
tdis  
tclk  
D15  
D14  
D 0  
D1  
Figure 53. Interface Timing Diagram: 4-Wire CS Mode With a Busy Indicator  
When the conversion is complete, the device enters acquisition phase, powers down, forces SDO out of 3-state,  
and outputs a busy indicator bit (low level). The device outputs the MSB of the data on the first SCLK falling  
edge after the conversion is complete and continues to output the next lower data bits on every subsequent  
SCLK falling edge. SDO goes to 3-state after the 17th SCLK falling edge or when SDI (CS) is high, whichever  
occurs first.  
Care must be taken so that CONVST and SDI are not both low at any time during the cycle.  
9.4.3 Daisy-Chain Mode  
Daisy-chain mode is selected if SDI is low at the time of the CONVST rising edge. This mode is useful to reduce  
wiring and hardware requirements (such as digital isolators in applications where multiple ADC devices are  
used). In this mode, all devices are connected in a chain (the SDO of one device is connected to the SDI of the  
next device) and data transfer is analogous to a shift register.  
As in CS mode, this mode offers operation with or without a busy indicator. This section discusses these  
interface options in detail.  
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Device Functional Modes (continued)  
9.4.3.1 Daisy-Chain Mode Without a Busy Indicator  
A connection diagram for this mode is shown in Figure 54. The SDI for device 1 is tied to ground and the SDO of  
device 1 goes to the SDI of device 2, and so on. The SDO of the last device in the chain goes to the digital host.  
CONVST for all devices in the chain are tied together. There is no CS signal in this mode.  
CNV  
CONVST  
CONVST  
SDI  
SDO  
SDI  
SDO  
SDI  
SCLK  
SCLK  
CLK  
Device 1  
Device 2  
Digital Host  
Figure 54. Connection Diagram: Daisy-Chain Mode Without a Busy Indicator (SDI = 0)  
The device SDO is driven low when SDI low selects daisy-chain mode and the device samples the analog input  
and enters the conversion phase. SCLK must be low at the CONVST rising edge (as shown in Figure 55) so that  
the device does not generate a busy indicator at the end of the conversion. In this mode, CONVST remains high  
from the start of the conversion until all data bits are read. When started, the conversion continues regardless of  
the state of SCLK.  
t
cyc  
CONVST  
Phase  
t6  
tcnv  
tacq  
Acquisition  
Acquisition  
t7  
Conversion  
t2  
tclkl  
SCLK  
1
2
16  
tclkh  
17  
18  
32  
15  
31  
t8  
tclk  
#1-D1  
SDO 1, SDI 2  
SDO 2  
#1-D15 #1-D14  
t3  
#1-D0  
#
#2-D15 #2-D14  
2-D1  
#2-D0 #1-D15 #1-D14  
#1-D1  
#1-D0  
Figure 55. Interface Timing Diagram: Daisy-Chain Mode Without a Busy Indicator  
At the end of the conversion, every device in the chain initiates an output of its conversion data starting with the  
MSB bit. Furthermore, the next lower data bit is output on every subsequent SCLK falling edge. While every  
device outputs its data on the SDO pin, each device also receives the previous device data on the SDI pin (other  
than device 1) and stores the data in the shift register. The device latches incoming data on every SCLK falling  
edge. The SDO of the first device in the chain goes low after the 16th SCLK falling edge. All subsequent devices  
in the chain output the stored data from the previous device in MSB-first format immediately following their own  
data word. 16 × N clocks must read data for N devices in the chain.  
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Device Functional Modes (continued)  
9.4.3.2 Daisy-Chain Mode With a Busy Indicator  
A connection diagram for this mode is shown in Figure 56. The SDI for device 1 is wired to its CONVST and the  
CONVST for all devices in the chain are wired together. The SDO of device 1 goes to the SDI of device 2, and  
so on. The SDO of the last device in the chain goes to the digital host. There is no CS signal in this mode.  
CNV  
+VBD  
CONVST  
SCLK  
CONVST  
SCLK  
SDI  
SDO  
SDI  
SDO  
SDI  
IRQ  
CLK  
Device 1  
Device 2  
Digital Host  
Figure 56. Connection Diagram: Daisy Chain Mode With a Busy Indicator (SDI = 0)  
On the CONVST rising edge, all devices in the chain sample the analog input and enter the conversion phase.  
For the first device, SDI and CONVST are wired together and the setup time of SDI to the CONVST rising edge  
is adjusted so that the device still enters daisy-chain mode even though SDI and CONVST rise together. SCLK  
must be high at the CONVST rising edge (as shown in Figure 57) so that the device generates a busy indicator  
at the end of the conversion. In this mode, CONVST remains high from the start of the conversion until all data  
bits are read. When started, the conversion continues regardless of the state of SCLK.  
tcyc  
t6  
CONVST  
tcnv  
tacq  
Conversion  
Acquisition  
Phase  
SCLK  
Acquisition  
t7  
t2  
tclkl  
1
17  
tclkh  
#1-D1 #1-D0  
18  
33  
2
3
16  
19  
32  
tclk  
t8  
#1-D15 #1-D14  
t3  
SDO 1, SDI 2  
SDO 2  
#2-D15 #2-D14  
#2-D1 #2-D0 #1-D15 #1-D14  
#1-D1 #1-D0  
Figure 57. Interface Timing Diagram: Daisy Chain Mode With a Busy Indicator  
At the end of the conversion, all devices in the chain generate busy indicators. On the first SCLK falling edge  
following the busy indicator bit, all devices in the chain output their conversion data starting with the MSB bit.  
Afterwards, the next lower data bit is output on every SCLK falling edge. While every device outputs its data on  
the SDO pin, each device also receives the previous device data on the SDI pin (except for device 1) and stores  
the data in the shift register. Each device latches incoming data on every SCLK falling edge. The SDO of the first  
device in the chain goes high after the 17th SCLK falling edge. All subsequent devices in the chain output the  
stored data from the pervious device in MSB-first format immediately following their own data word. 16 × N + 1  
clock pulses are required to read data for N devices in the chain.  
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10 Application and Implementation  
NOTE  
Information in the following applications sections is not part of the TI component  
specification, and TI does not warrant its accuracy or completeness. TI’s customers are  
responsible for determining suitability of components for their purposes. Customers should  
validate and test their design implementation to confirm system functionality.  
10.1 Application Information  
To obtain the best performance from a high-precision successive approximation register (SAR) analog-to-digital  
converter (ADC), the reference driver and the input driver circuit must be optimized. This section details general  
principles for designing such drivers, followed by typical application circuits designed using the ADS8339.  
10.1.1 ADC Reference Driver  
A simplified circuit diagram for such a reference driver is shown in Figure 58.The external voltage reference must  
provide a low-noise, low-drift, highly-accurate voltage for the ADC reference input pin. The output broadband  
noise of most voltage references can be in the order of a few hundred μVRMS, which degrades the conversion  
result. To prevent any noticeable degradation in the noise performance of the ADC, the noise from the voltage  
reference must be filtered. This filtering can be done by using a low-pass filter with a cutoff frequency of a few  
hundred hertz.  
RREF_FLT  
Voltage  
Reference  
Buffer  
REFIN  
CREF_FLT  
ADC  
CBUF_FLT  
Figure 58. Reference Driver Schematic  
During the conversion process, the ADS8339 switches binary-weighted capacitors onto the reference pin  
(REFIN). The switching frequency is proportional to the internal conversion clock frequency. The dynamic charge  
required by the capacitors is a function of the ADC input voltage and the reference voltage. Design the reference  
driver circuit such that the dynamic loading of the capacitors can be handled without degrading the noise and  
linearity performance of the ADC.  
When the noise of the voltage reference is band-limited the next step is to design a reference buffer that can  
drive the dynamic load posed during the conversion cycle. The buffer must regulate the voltage at the REFIN pin  
of the device such that the reference voltage to the ADC stays within 1 LSB of an error at the start of each  
conversion. This condition necessitates the use of a large capacitor, CBUF_FLT (as shown in Figure 58). The  
amplifier selected as the buffer must have very low offset, temperature drift, and output impedance to drive the  
internal binary-weighted capacitors at the REFIN pin of the ADC without any stability issues.  
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Application Information (continued)  
10.1.1.1 Reference Driver Circuit  
A more detailed circuit shows the schematic (as shown in Figure 59) of a complete reference driver circuit that  
generates 4.5 V dc using a single 5-V supply. This circuit can drive the reference pin of the ADS8339 at  
sampling rates of up to 250 kSPS. The 4.5-V reference voltage is generated using a high-precision, low-noise  
REF5045. The output broadband noise of the reference is further filtered using a low-pass filter with a 3-dB cutoff  
frequency of 16 Hz.  
20 k  
AVDD  
1 µF  
REF5045  
-
VIN  
-
1 kꢀ  
1 µF  
+
AVDD  
+
10 kꢀ  
THS4281  
+
0.2 ꢀ  
+
OUT  
GND  
1 µF  
OPA333  
AVDD  
+VA  
REFIN  
IN+  
AVDD  
1 µF  
10 µF  
Device  
-IN  
GND  
Figure 59. Reference Driver Circuit Schematic  
The driver also includes a THS4281 and an OPA333. This composite architecture provides superior ac and dc  
performance at reduced power levels compared to a single high-performance amplifier.  
The THS4281 is a high-bandwidth amplifier with very low output impedance of 1 Ω at a frequency of 1 MHz. The  
low output impedance makes the THS4281 a good choice for driving large capacitive loads. The high offset and  
drift specifications of the THS4281 are corrected using a dc-correcting amplifier (OPA333) inside the feedback  
loop. Thus, the composite scheme also inherits the extremely low offset and temperature drift specifications of  
the OPA333.  
10.1.2 ADC Input Driver  
The input driver circuit for a high-precision ADC mainly consists of two parts: a driving amplifier and an RC filter.  
An amplifier is used for signal conditioning the input voltage. The low output impedance of the amplifier functions  
as a buffer between the signal source and the sampling capacitor input of the ADC. The RC filter functions as an  
antialiasing filter that band-limits the wideband noise contributed by the front-end circuit. The RC filter also helps  
attenuate the sampling capacitor charge injection from the switched-capacitor input stage of the ADC. Careful  
design of the front-end circuit is critical to meet the linearity and noise performance of a high-precision, 16-bit  
ADC such as the ADS8339.  
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Application Information (continued)  
10.1.2.1 Input Amplifier Selection  
Selection criteria for the input amplifier is dependent on the input signal type as well as performance goals of the  
data acquisition system. Some key specifications to consider when selecting an amplifier to drive the inputs of  
the ADS8339 are:  
Small-signal bandwidth. The small-signal bandwidth of the input amplifier must be as high as possible for a  
given power budget. Higher bandwidth reduces the closed-loop output impedance of the amplifier, thus  
allowing the amplifier to more easily drive the RC filter (with low cutoff frequency) at the inputs of the ADC.  
Higher bandwidth also minimizes harmonic distortion at higher input frequencies. In order to maintain overall  
stability, the amplifier bandwidth must satisfy Equation 1:  
§
·
1
¨
¨
¸
¸
Unity Gain Bandwidth t 4u  
2S  
u(RFLT RFLT )uCFLT  
©
¹
(1)  
Noise. Noise contribution of the front-end amplifiers must be as low as possible to prevent any degradation in  
the overall SNR performance of the system. As a rule of thumb, to ensure that the noise performance of the  
data acquisition system is not limited by the front-end circuit, keep the total noise contribution from the front-  
end circuit below 20% of the input-referred noise of the ADC. Noise from the input driver circuit gets band-  
limited by the RC filter, as given in Equation 2.  
2
SNR  
dB  
§
¨
·
¸
V
§
¨
·
¸
1
_ AMP_PP  
S
2
1
5
VREF  
2
20  
en2_RMS  
u
u f3dB  
d
u
u10  
f
©
¹
NG u 2 u  
¨
¨
¸
¸
6.6  
©
¹
where:  
V1 / f_AMP_PP is the peak-to-peak flicker noise in µV,  
en_RMS is the amplifier broadband noise density in nV/Hz,  
f–3dB is the 3-dB bandwidth of the RC filter, and  
NG is the noise gain of the front-end circuit, which is equal to 1 in a buffer configuration.  
(2)  
Distortion. The ADC and the input driver introduce nonlinearity in a data acquisition block. As a rule of thumb,  
to ensure that the distortion performance of the data acquisition system is not limited by the front-end circuit,  
the distortion of the input driver must be at least 10 dB lower than the distortion of the ADC, as given in  
Equation 3.  
THDAMP d THDADC 10  
dB  
(3)  
Settling Time. For dc signals with fast transients that are common in a multiplexed application, the input signal  
must settle to a 16-bit accuracy level at the device inputs during the acquisition time. This condition is critical  
in maintaining the overall linearity of the ADC. Typically, the amplifier data sheets specify the output settling  
performance only up to 0.1% to 0.001%, which may not be sufficient for the desired 16-bit accuracy.  
Therefore, the settling behavior of the input driver must always be verified by TINA™-SPICE simulations  
before selecting the amplifier.  
10.1.2.2 Antialiasing Filter  
Converting analog-to-digital signals requires sampling the input signal at a constant rate. Any frequency content  
in the input signal that is beyond half the sampling frequency is folded back into the low-frequency spectrum,  
which is undesirable. This process is called aliasing. An analog antialiasing filter must be used to remove the  
high-frequency component (beyond half the sampling frequency) from the input signal before being sampled by  
the ADC.  
An antialiasing filter is designed as a low-pass, RC filter for which the 3-dB bandwidth is optimized based on  
specific application requirements. For dc signals with fast transients (including multiplexed input signals), a high-  
bandwidth filter is designed to allow for accurate settling of the signal at the input of the ADC. For ac signals,  
keep the filter bandwidth as low as possible to band-limit the noise fed into the ADC, which improves the signal-  
to-noise ratio (SNR) performance of the system.  
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Application Information (continued)  
The RC filter also helps absorb the sampling charge injection from the switched-capacitor input of the ADC. A  
filter capacitor, CFLT, is connected across the inputs of the ADC (as shown in Figure 60). This capacitor helps  
absorb the sampling capacitor charge injection in addition to functioning as a charge bucket to quickly charge the  
internal sample-and-hold capacitors during the acquisition phase.  
When selecting this capacitor, as a rule of thumb, the capacitor value must be at least 10 times the ADC  
sampling capacitor specified on the data sheet. The input sampling capacitance is approximately 59 pF for the  
ADS8339. The value of CFLT must be greater than 590 pF. The capacitor must be a COG- or NPO-type because  
these capacitor types have a high-Q, low-temperature coefficient and stable electrical characteristics under  
varying voltages, frequency, and time.  
RFLT ”ꢀ44 ꢀ  
IN+  
1
f3dB  
 
CFLT •ꢀꢀ590 pF  
Device  
2Su  
RFLT  RFLT u CFLT  
-IN  
GND  
RFLT ”ꢀ44 ꢀ  
Figure 60. Antialiasing Filter  
NOTE  
Driving capacitive loads can degrade the phase margin of the input amplifiers, thus  
making the amplifier marginally unstable. To avoid stability issues, series isolation  
resistors (RFLT) are used at the output of the amplifiers. A higher value of RFLT is helpful  
from the amplifier stability perspective. Distortion increases with source impedance, input  
signal frequency, and input signal amplitude. The selection of RFLT thus requires a balance  
between stability and distortion of the design.  
TI recommends limiting the value of RFLT to a maximum of 44 Ω in order to avoid any  
significant degradation in linearity performance for the ADS8339. The tolerance of  
resistors can be 1% because the differential capacitor at the input balances the effects  
resulting from resistor mismatch.  
The input amplifier bandwidth must be much higher than the cutoff frequency of the  
antialiasing filter. TI strongly recommends running a SPICE simulation to confirm that the  
amplifier has more than 40° phase margin with the filter that is designed. Simulation is  
critical because some amplifiers may require more bandwidth than others to drive similar  
filters. If an amplifier has less than 40° phase margin with 44-Ω resistors, using a different  
amplifier with higher bandwidth or reducing the filter cutoff frequency with a larger  
differential capacitor is advisable.  
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10.2 Typical Application  
This section describes a typical application circuit using the ADS8339. The circuit is optimized to derive the best  
ac performance. For simplicity, power-supply decoupling capacitors are not shown in these circuit diagrams.  
Reference Drive Circuit  
20 k:  
1 PF  
-
-
THS4281  
1 k:  
AVDD  
+
+
OPA333  
REF5045  
1 k:  
1 PF  
+
0.2 :  
10 PF  
+
1 PF  
Vout  
Vin  
AVDD  
AVDD  
1 PF  
GND  
16-Bit, 250-kSPS  
SAR ADC  
Input Driver  
1 k:  
1 k:  
AVDD  
AVDD  
VIN  
+
-
REFIN AVDD  
4.7 :  
IN+  
OPA836  
CONVST  
+
10 nF  
Device  
IN  
VCM  
CONVST  
GND  
4.7 :  
Figure 61. Single-Ended Input DAQ Circuit for Lowest Distortion and Noise at 250 kSPS  
10.2.1 Design Requirements  
The application circuit for the ADS8339 (as shown in Figure 61) is optimized for lowest distortion and noise for a  
10-kHz input signal to achieve:  
–106-dB THD and 93-dB SNR at a maximum specified throughput of 250 kSPS.  
10.2.2 Detailed Design Procedure  
In the application circuit, the input signal is processed through a high-bandwidth, low-distortion, inverting amplifier  
and a low-pass RC filter before being fed to the ADC.  
The reference driver circuit illustrated in Figure 59 generates 4.5 V dc using a single 5-V supply. This circuit is  
suitable to drive the reference at sampling rates of up to 250 kSPS. To keep the noise low, a high-precision  
REF5045 is used. The output broadband noise of the reference is heavily filtered by a low-pass filter with a 3-dB  
cutoff frequency of 16 Hz.  
The reference buffer is designed in a composite architecture to achieve superior dc and ac performance at  
reduced power consumption. The low output impedance makes the THS4281 a good choice for driving large  
capacitive loads that regulate the voltage at the reference input pin of the ADC. The high offset and drift  
specifications of the THS4281 are corrected by using a dc-correcting amplifier (such as the OPA333) inside the  
feedback loop.  
For the input driver, as a rule of thumb, the distortion of the amplifier must be at least 10 dB less than the ADC  
distortion. The distortion resulting from variation in the common-mode signal is eliminated by using the driver in  
an inverting gain configuration. This configuration also eliminates the need for an amplifier that supports rail-to-  
rail input. The OPA836 is a good choice for an input driver because of its low-power consumption and  
exceptional ac performance (such as low distortion and high bandwidth).  
Finally, the components of the antialiasing filter are chosen such that the noise from the front-end circuit is kept  
low without adding distortion to the input signal.  
30  
Copyright © 2014, Texas Instruments Incorporated  
 
ADS8339  
www.ti.com.cn  
ZHCSCX4A JUNE 2014REVISED OCTOBER 2014  
Typical Application (continued)  
10.2.3 Application Curve  
To ensure that the circuit meets the design requirements, the dc noise performance and the frequency content of  
the digitized output is verified. The input is set to a fixed dc value at half the reference. The histogram of the  
output code shows a peak-to-peak noise distribution of four codes which translates to 14 bits of noise-free bits.  
An ac signal at 10 kHz is then fed to the input. The FFT of the output shows a THD of –106 dB and an SNR of  
92 dB, which is close to the design requirements.  
0
±10  
±20  
±30  
±40  
±50  
±60  
±70  
±80  
1800  
1600  
1400  
1200  
1000  
800  
600  
400  
200  
0
1685  
HD2 -107.45  
±90  
±100  
±110  
±120  
±130  
±140  
±150  
290  
72  
1
32760  
32761  
32762  
32763  
0
25  
50  
75  
100  
125  
ADC Output Code  
Frequency (kHz)  
C044  
C043  
SNR = 92 dB, THD = – 106 dB, number of samples = 1024  
VDIFF = Vref / 2, 2048 data points, standard deviation = 0.41 bits  
Figure 63. 0.4-dBFS, 10-kHz Sine Input FFT  
Figure 62. DC Input Histogram at Mid-Code  
10.3 Do's and Don'ts  
Use multiple capacitors to decouple the dynamic current transients at various input pins including the  
reference, supply, and input signal.  
Parasitic inductance can induce ringing on the clock signal. Include a resistor on the SCLK pin to clean up the  
clock edges.  
11 Power-Supply Recommendations  
The ADS8339 is designed to operate from an analog supply voltage range between 4.5 V and 5.5 V and a digital  
supply voltage range between 2.375 V and 5.5 V. Both supplies must be well regulated. The analog supply must  
always be greater than or equal to the digital supply. A 1-μF ceramic decoupling capacitor is required at each  
supply pin and must be placed as close as possible to the device.  
Copyright © 2014, Texas Instruments Incorporated  
31  
ADS8339  
ZHCSCX4A JUNE 2014REVISED OCTOBER 2014  
www.ti.com.cn  
12 Layout  
12.1 Layout Guidelines  
Figure 64 shows one of the board layouts as an example when using ADS8339 in a circuit.  
A printed circuit board (PCB) board with at least four layers is recommended to keep all critical components  
on the top layer.  
Analog input signals and the reference input signals must be kept away from noise sources. Crossing digital  
lines with the analog signal path should be avoided. The analog input and the reference signals are routed on  
to the left side of the board and the digital connections are routed on the right side of the device.  
Due to the dynamic currents that occur during conversion and data transfer, each supply pin (AVDD and  
DVDD) must have a decoupling capacitor that keeps the supply voltage stable. TI recommends using one 1-  
μF ceramic capacitor at each supply pin.  
A layout that interconnects the converter and accompanying capacitors with the low inductance path is critical  
for achieving optimal performance. Using 15-mil vias to interconnect components to a solid analog ground  
plane at the subsequent inner layer minimizes stray inductance. Avoid placing vias between the supply pin  
and the decoupling capacitor. Any inductance between the supply capacitor and the supply pin of the  
converter must be kept to less than 5 nH by placing the capacitor within 0.2 inches from the supply or input  
pins of the ADS8339 and by using 20-mil traces, as shown in Figure 64.  
Dynamic currents are also present at the REFIN pin during the conversion phase. Therefore, good decoupling  
is critical to achieve optimal performance. The inductance between the reference capacitor and the REFIN pin  
must be kept to less than 2 nH by placing the capacitor within 0.1 inches from the REFIN pin and by using  
20-mil traces.  
A single 10-μF, X7R-grade, 0805-size ceramic capacitor with at least a 10-V rating is recommended for good  
performance over temperature range.  
A small, 0.1-Ω to 0.47-Ω, 0603-size resistor placed in series with the reference capacitor keeps the overall  
impedance low and constant, especially at very high frequencies.  
Avoid using additional lower value capacitors because the interactions between multiple capacitors can affect  
the ADC performance at higher sampling rates.  
Place the RC filters immediately next to the input pins. Among surface-mount capacitors, COG (NPO)  
ceramic capacitors provide the best capacitance precision. The type of dielectric used in COG (NPO) ceramic  
capacitors provides the most stable electrical properties over voltage, frequency, and temperature changes.  
12.2 Layout Example  
GND  
1PF  
1PF  
10PF  
GND  
0.1Ot 0.47O  
GND  
DVDD  
REF  
47O  
1: REF  
10: DVDD  
Analog Input  
2: AVDD  
3: AINP  
4: AINN  
5: GND  
9: SDI  
8: SCLK  
7: SDO  
47O  
GND  
6: CONVST  
SDO  
GND  
47O  
Figure 64. Board Layout Example  
32  
版权 © 2014, Texas Instruments Incorporated  
 
ADS8339  
www.ti.com.cn  
ZHCSCX4A JUNE 2014REVISED OCTOBER 2014  
13 器件和文档支持  
13.1 文档支持  
13.1.1 相关文档ꢀ  
REF5045 数据表》(文献编号 SBOS410)  
THS4281 数据表》(文献编号 SLOS432)  
OPA333 数据表》(文献编号 SBOS351)  
OPA836 数据表》(文献编号 SLOS713)  
ADS886xEVM-PDK ADS83x9EVM-PDK 用户指南》(文献编号 SBAU233)  
13.2 商标  
TINA is a trademark of Texas Instruments Inc..  
SPI is a trademark of Motorola.  
All other trademarks are the property of their respective owners.  
13.3 静电放电警告  
ESD 可能会损坏该集成电路。德州仪器 (TI) 建议通过适当的预防措施处理所有集成电路。如果不遵守正确的处理措施和安装程序 , 可  
能会损坏集成电路。  
ESD 的损坏小至导致微小的性能降级 , 大至整个器件故障。 精密的集成电路可能更容易受到损坏 , 这是因为非常细微的参数更改都可  
能会导致器件与其发布的规格不相符。  
13.4 术语表  
SLYZ022 TI 术语表。  
这份术语表列出并解释术语、首字母缩略词和定义。  
14 机械封装和可订购信息  
以下页中包括机械封装和可订购信息。 这些信息是针对指定器件可提供的最新数据。 这些数据会在无通知且不对  
本文档进行修订的情况下发生改变。 欲获得该数据表的浏览器版本,请查阅左侧的导航栏。  
版权 © 2014, Texas Instruments Incorporated  
33  
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Copyright © 2014, 德州仪器半导体技术(上海)有限公司  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
PACKAGING INFORMATION  
Orderable Device  
Status Package Type Package Pins Package  
Eco Plan  
Lead finish/  
Ball material  
MSL Peak Temp  
Op Temp (°C)  
Device Marking  
Samples  
Drawing  
Qty  
(1)  
(2)  
(3)  
(4/5)  
(6)  
ADS8339IDGSR  
ADS8339IDGST  
ACTIVE  
ACTIVE  
VSSOP  
VSSOP  
DGS  
DGS  
10  
10  
2500 RoHS & Green  
250 RoHS & Green  
SN  
Level-2-260C-1 YEAR  
Level-2-260C-1 YEAR  
-40 to 85  
-40 to 85  
8339  
8339  
SN  
(1) The marketing status values are defined as follows:  
ACTIVE: Product device recommended for new designs.  
LIFEBUY: TI has announced that the device will be discontinued, and a lifetime-buy period is in effect.  
NRND: Not recommended for new designs. Device is in production to support existing customers, but TI does not recommend using this part in a new design.  
PREVIEW: Device has been announced but is not in production. Samples may or may not be available.  
OBSOLETE: TI has discontinued the production of the device.  
(2) RoHS: TI defines "RoHS" to mean semiconductor products that are compliant with the current EU RoHS requirements for all 10 RoHS substances, including the requirement that RoHS substance  
do not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered at high temperatures, "RoHS" products are suitable for use in specified lead-free processes. TI may  
reference these types of products as "Pb-Free".  
RoHS Exempt: TI defines "RoHS Exempt" to mean products that contain lead but are compliant with EU RoHS pursuant to a specific EU RoHS exemption.  
Green: TI defines "Green" to mean the content of Chlorine (Cl) and Bromine (Br) based flame retardants meet JS709B low halogen requirements of <=1000ppm threshold. Antimony trioxide based  
flame retardants must also meet the <=1000ppm threshold requirement.  
(3) MSL, Peak Temp. - The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder temperature.  
(4) There may be additional marking, which relates to the logo, the lot trace code information, or the environmental category on the device.  
(5) Multiple Device Markings will be inside parentheses. Only one Device Marking contained in parentheses and separated by a "~" will appear on a device. If a line is indented then it is a continuation  
of the previous line and the two combined represent the entire Device Marking for that device.  
(6)  
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lines if the finish value exceeds the maximum column width.  
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TI and TI suppliers consider certain information to be proprietary, and thus CAS numbers and other limited information may not be available for release.  
In no event shall TI's liability arising out of such information exceed the total purchase price of the TI part(s) at issue in this document sold by TI to Customer on an annual basis.  
Addendum-Page 1  
PACKAGE OPTION ADDENDUM  
www.ti.com  
10-Dec-2020  
Addendum-Page 2  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
18-Aug-2020  
TAPE AND REEL INFORMATION  
*All dimensions are nominal  
Device  
Package Package Pins  
Type Drawing  
SPQ  
Reel  
Reel  
A0  
B0  
K0  
P1  
W
Pin1  
Diameter Width (mm) (mm) (mm) (mm) (mm) Quadrant  
(mm) W1 (mm)  
ADS8339IDGSR  
ADS8339IDGST  
VSSOP  
VSSOP  
DGS  
DGS  
10  
10  
2500  
250  
330.0  
180.0  
12.4  
12.4  
5.3  
5.3  
3.4  
3.4  
1.4  
1.4  
8.0  
8.0  
12.0  
12.0  
Q1  
Q1  
Pack Materials-Page 1  
PACKAGE MATERIALS INFORMATION  
www.ti.com  
18-Aug-2020  
*All dimensions are nominal  
Device  
Package Type Package Drawing Pins  
SPQ  
Length (mm) Width (mm) Height (mm)  
ADS8339IDGSR  
ADS8339IDGST  
VSSOP  
VSSOP  
DGS  
DGS  
10  
10  
2500  
250  
367.0  
210.0  
367.0  
185.0  
35.0  
35.0  
Pack Materials-Page 2  
PACKAGE OUTLINE  
DGS0010A  
VSSOP - 1.1 mm max height  
S
C
A
L
E
3
.
2
0
0
SMALL OUTLINE PACKAGE  
C
SEATING PLANE  
0.1 C  
5.05  
4.75  
TYP  
PIN 1 ID  
AREA  
A
8X 0.5  
10  
1
3.1  
2.9  
NOTE 3  
2X  
2
5
6
0.27  
0.17  
10X  
3.1  
2.9  
1.1 MAX  
0.1  
C A  
B
B
NOTE 4  
0.23  
0.13  
TYP  
SEE DETAIL A  
0.25  
GAGE PLANE  
0.15  
0.05  
0.7  
0.4  
0 - 8  
DETAIL A  
TYPICAL  
4221984/A 05/2015  
NOTES:  
1. All linear dimensions are in millimeters. Any dimensions in parenthesis are for reference only. Dimensioning and tolerancing  
per ASME Y14.5M.  
2. This drawing is subject to change without notice.  
3. This dimension does not include mold flash, protrusions, or gate burrs. Mold flash, protrusions, or gate burrs shall not  
exceed 0.15 mm per side.  
4. This dimension does not include interlead flash. Interlead flash shall not exceed 0.25 mm per side.  
5. Reference JEDEC registration MO-187, variation BA.  
www.ti.com  
EXAMPLE BOARD LAYOUT  
DGS0010A  
VSSOP - 1.1 mm max height  
SMALL OUTLINE PACKAGE  
10X (1.45)  
(R0.05)  
TYP  
SYMM  
10X (0.3)  
1
5
10  
SYMM  
6
8X (0.5)  
(4.4)  
LAND PATTERN EXAMPLE  
SCALE:10X  
SOLDER MASK  
OPENING  
SOLDER MASK  
OPENING  
METAL UNDER  
SOLDER MASK  
METAL  
0.05 MAX  
ALL AROUND  
0.05 MIN  
ALL AROUND  
SOLDER MASK  
DEFINED  
NON SOLDER MASK  
DEFINED  
SOLDER MASK DETAILS  
NOT TO SCALE  
4221984/A 05/2015  
NOTES: (continued)  
6. Publication IPC-7351 may have alternate designs.  
7. Solder mask tolerances between and around signal pads can vary based on board fabrication site.  
www.ti.com  
EXAMPLE STENCIL DESIGN  
DGS0010A  
VSSOP - 1.1 mm max height  
SMALL OUTLINE PACKAGE  
10X (1.45)  
SYMM  
(R0.05) TYP  
10X (0.3)  
8X (0.5)  
1
5
10  
SYMM  
6
(4.4)  
SOLDER PASTE EXAMPLE  
BASED ON 0.125 mm THICK STENCIL  
SCALE:10X  
4221984/A 05/2015  
NOTES: (continued)  
8. Laser cutting apertures with trapezoidal walls and rounded corners may offer better paste release. IPC-7525 may have alternate  
design recommendations.  
9. Board assembly site may have different recommendations for stencil design.  
www.ti.com  
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