TI ADS8557IPM

ADS8556
ADS8557
ADS8558
www.ti.com ............................................................................................................................................... SBAS404A – OCTOBER 2006 – REVISED AUGUST 2009
16-, 14-, 12-Bit, Six-Channel, Simultaneous Sampling
ANALOG-TO-DIGITAL CONVERTERS
FEATURES
1
• Family of 16-, 14-, 12-Bit, Pin- and
Software-Compatible ADCs
• Six SAR ADCs Grouped in Three Pairs
• Maximum Data Rate Per Channel with Internal
Conversion Clock and Reference:
ADS8556: 630kSPS (PAR) or 450kSPS (SER)
ADS8557: 670kSPS (PAR) or 470kSPS (SER)
ADS8558: 730kSPS (PAR) or 500kSPS (SER)
• Maximum Data Rate with External Conversion
Clock and Reference:
800kSPS (PAR) or 530kSPS (SER)
• Pin-Selectable or Programmable Input Voltage
Ranges: Up to ±12V
• Excellent Signal-to-Noise Performance:
91.5dB (ADS8556)
85dB (ADS8557)
73.9dB (ADS8558)
• Programmable and Buffered Internal
Reference: 0.5V to 2.5V and 0.5V to 3.0V
• Comprehensive Power-Down Modes:
Deep Power-Down (Standby Mode)
Partial Power-Down
Auto-Nap Power-Down
• Selectable Parallel or Serial Interface
• Operating Temperature Range:
–40°C to +125°C
• LQFP-64 Package
2
DESCRIPTION
The ADS8556/7/8 contain six low-power, 16-, 14-, or
12-bit, successive approximation register (SAR)
based analog-to-digital converters (ADCs) with true
bipolar
inputs.
Each
channel
contains
a
sample-and-hold circuit that allows simultaneous
high-speed multi-channel signal acquisition.
The ADS8556/7/8 support data rates of up to
730kSPS in parallel interface mode or up to 500kSPS
if the serial interface is used. The bus width of the
parallel interface can be set to eight or 16 bits. In
serial mode, up to three output channels can be
activated.
The ADS8556/7/8 is specified over the full industrial
temperature range of –40°C to +125°C and is
available in an LQFP-64 package.
ADS8556
ADS8557
ADS8558
Clock
Generator
CONVST_A
Comparator
CH_A0
S/H
CDAC 1
AGND
BUSY/INT
RANGE/XCLK
Buffer
SAR Register 1/2
Control
Logic
REFC_A
CH_A1
S/H
HW/SW
REFEN/WR
STBY
RESET
CDAC 2
AGND
Comparator
CONVST_B
Comparator
CH_B0
S/H
CDAC 3
AGND
Buffer
SAR Register 3/4
Config
Register
REFC_B
CH_B1
APPLICATIONS
•
•
•
•
•
Power Quality Measurement
Protection Relays
Multi-Axis Motor Control
Programmable Logic Controllers
Industrial Data Acquisition
S/H
CDAC 4
AGND
Comparator
CONVST_C
Comparator
CH_C0
S/H
CDAC 5
AGND
Buffer
CS/FS
SAR Register 5/6
I/O
RD
DB[15:0]
WORD/BYTE
PAR/SER
REFC_C
CH_C1
S/H
CDAC 6
AGND
Comparator
Buffer
REF_IO
BVDD
String DAC
Internal 2.5V
Reference
BGND
AVDD
HVDD
AGND
HVSS
1
2
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.
All trademarks are the property of their respective owners.
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.
Copyright © 2006–2009, Texas Instruments Incorporated
ADS8556
ADS8557
ADS8558
SBAS404A – OCTOBER 2006 – REVISED AUGUST 2009 ............................................................................................................................................... www.ti.com
This integrated circuit can be damaged by ESD. Texas Instruments recommends that all integrated circuits be handled with
appropriate precautions. Failure to observe proper handling and installation procedures can cause damage.
ESD damage can range from subtle performance degradation to complete device failure. Precision integrated circuits may be more
susceptible to damage because very small parametric changes could cause the device not to meet its published specifications.
PACKAGE/ORDERING INFORMATION (1)
(1)
PRODUCT
RESOLUTION
(Bits)
PACKAGELEAD
PACKAGE
DESIGNATOR
ADS8556I
16
LQFP-64
PM
ADS8557I
14
LQFP-64
PM
ADS8558I
12
LQFP-64
PM
ORDERING
NUMBER
TRANSPORT
MEDIA, QUANTITY
ADS8556IPM
Tray, 160
ADS8556IPMR
Tape and Reel, 1000
ADS8557IPM
Tray, 160
ADS8557IPMR
Tape and Reel, 1000
ADS8558IPM
Tray, 160
ADS8558IPMR
Tape and Reel, 1000
For the most current package and ordering information see the Package Option Addendum at the end of this document, or see the TI
web site at www.ti.com.
ABSOLUTE MAXIMUM RATINGS (1)
Over operating free-air temperature range, unless otherwise noted.
ADS8556, ADS8557, ADS8558
UNIT
Supply voltage, HVDD to AGND
–0.3 to +18
V
Supply voltage, HVSS to AGND
–18 to +0.3
V
Supply voltage, AVDD to AGND
–0.3 to +6
V
Supply voltage, BVDD to BGND
–0.3 to +6
V
Analog input voltage
HVSS – 0.3 to HVDD + 0.3
V
Reference input voltage with respect to AGND
AGND – 0.3 to AVDD + 0.3
V
Digital input voltage with respect to BGND
BGND – 0.3 to BVDD + 0.3
V
Ground voltage difference AGND to BGND
Input current to all pins except supply
Maximum virtual junction temperature, TJ
ESD ratings
(1)
2
±0.3
V
–10 to +10
mA
+150
°C
Human body model (HBM)
JEDEC standard 22, test method A114-C.01, all pins
±2000
V
Charged device model (CDM)
JEDEC standard 22, test method C101, all pins
±500
V
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.
Copyright © 2006–2009, Texas Instruments Incorporated
Product Folder Link(s): ADS8556 ADS8557 ADS8558
ADS8556
ADS8557
ADS8558
www.ti.com ............................................................................................................................................... SBAS404A – OCTOBER 2006 – REVISED AUGUST 2009
RECOMMENDED OPERATING CONDITIONS
MIN
Supply voltage, AVDD to AGND
Supply voltage, BVDD to BGND
Input supply voltage, HVDD to AGND
Input supply voltage, HVSS to AGND
MAX
UNIT
4.5
5
5.5
V
Low-voltage levels
2.7
3.0
3.6
V
5V logic levels
4.5
5
5.5
V
Range 1 (±2 × VREF)
2 × VREF
16.5
V
Range 2 (±4 × VREF)
4 × VREF
16.5
V
Range 1 (±2 × VREF)
–16.5
–2 × VREF
V
Range 2 (±4 × VREF)
–16.5
–4 × VREF
V
3.0
V
Reference input voltage (VREF)
0.5
Analog inputs
(also see the Analog Inputs section)
TYP
2.5
Range 1 (±2 × VREF)
–2 × VREF
+2 × VREF
V
Range 1 (±4 × VREF)
–4 × VREF
+4 × VREF
V
–40
+125
°C
Operating ambient temperature range, TA
DISSIPATION RATINGS (1)
(1)
PACKAGE
DERATING FACTOR
ABOVE TA = +25°C
TA ≤ +25°C
POWER RATING
TA = +70°C
POWER RATING
TA = +85°C
POWER RATING
TA = +125°C
POWER RATING
LQFP-64
20.8mW/°C
2.60W
1.66W
1.35W
0.52W
Based on High-K θJA.
THERMAL CHARACTERISTICS
Over recommended operating conditions, unless otherwise noted.
ADS8556, ADS8557, ADS8558
PARAMETER
θJA
Junction-to-air thermal resistance
θJC
Junction-to-case thermal
resistance
PD
(1)
Device power dissipation
TEST CONDITIONS
MIN
TYP
MAX
UNIT
Low-K thermal resistance (1)
74
°C/W
High-K thermal resistance (1)
48
°C/W
16
°C/W
ADS8556, HVDD = +15V, HVSS = –15V, AVDD = 5V,
BVDD = 3V, and fDATA = maximum
251.7
298.5
mW
ADS8557, HVDD = +15V, HVSS = –15V, AVDD = 5V,
BVDD = 3V, and fDATA = maximum
253.2
303.0
mW
ADS8558, HVDD = +15V, HVSS = –15V, AVDD = 5V,
BVDD = 3V, and fDATA = maximum
262.2
318.0
mW
Modeled in accordance with the Low-K or High-K thermal metric definitions of EIA/JESD51-3.
Copyright © 2006–2009, Texas Instruments Incorporated
Product Folder Link(s): ADS8556 ADS8557 ADS8558
3
ADS8556
ADS8557
ADS8558
SBAS404A – OCTOBER 2006 – REVISED AUGUST 2009 ............................................................................................................................................... www.ti.com
ELECTRICAL CHARACTERISTICS: ADS8556
Over recommended operating free-air temperature range of –40°C to +125°C, AVDD = 4.5V to 5V, BVDD = 2.7V to 5.5V,
HVDD = 10V to 15V, HVSS = –15V to –10V, VREF = 2.5V (internal), and fDATA = 630kSPS in parallel mode or 450kSPS in
serial mode, unless otherwise noted.
ADS8556
PARAMETER
CONDITIONS
TYP (1)
MIN
MAX
UNIT
DC ACCURACY
Resolution
16
No missing codes
Integral linearity error
Differential linearity error
Bits
16
INL
DNL
At TA = –40°C to +85°C
–3
At TA = –40°C to +125°C
–4
At TA = –40°C to +85°C
–1
At TA = –40°C to +125°C
–1
–4.0
Offset error
Offset error drift
Bits
±1.5
3
LSB
±1.5
4
LSB
±0.75
1.5
LSB
±0.75
2
LSB
±0.8
4.0
Gain error
Referenced to voltage at REFIO
Gain error drift
Referenced to voltage at REFIO
±6
ppm/°C
PSRR At output code FFFFh, related to AVDD
60
dB
Power-supply rejection ratio
–0.75
±0.25
mV
µV/°C
±3.5
0.75
%FSR
SAMPLING DYNAMICS
Acquisition time
tACQ
Conversion time per ADC
tCONV
Internal conversion clock period
tCCLK
Throughput rate
fDATA
280
ns
1.26
µs
18.5
tCCLK
68.0
ns
Parallel interface,
internal clock and reference
630
kSPS
Serial interface,
internal clock and reference
450
kSPS
AC ACCURACY
Signal-to-noise ratio
Signal-to-noise ratio + distortion
Total harmonic distortion (2)
Spurious-free dynamic range
Channel-to-channel isolation
–3dB small-signal bandwidth
(1)
(2)
4
SNR
SINAD
THD
SFDR
At fIN = 10kHz, TA = –40°C to +85°C
90
91.5
dB
At fIN = 10kHz, TA = –40°C to +125°C
89
91.5
dB
At fIN = 10kHz, TA = –40°C to +85°C
87
89.5
dB
86.5
89.5
At fIN = 10kHz, TA = –40°C to +125°C
dB
At fIN = 10kHz, TA = –40°C to +85°C
–94
–90
At fIN = 10kHz, TA = –40°C to +125°C
–94
–89.5
At fIN = 10kHz, TA = –40°C to +85°C
90
At fIN = 10kHz, TA = –40°C to +125°C
89.5
At fIN = 10kHz
dB
95
dB
95
dB
100
dB
In 4 × VREF mode
48
MHz
In 2 × VREF mode
24
MHz
All values are at TA = +25°C.
Calculated on the first nine harmonics of the input frequency.
Copyright © 2006–2009, Texas Instruments Incorporated
Product Folder Link(s): ADS8556 ADS8557 ADS8558
ADS8556
ADS8557
ADS8558
www.ti.com ............................................................................................................................................... SBAS404A – OCTOBER 2006 – REVISED AUGUST 2009
ELECTRICAL CHARACTERISTICS: ADS8557
Over recommended operating free-air temperature range of –40°C to +125°C, AVDD = 4.5V to 5.5V, BVDD = 2.7V to 5.5V,
HVDD = 10V to 15V, HVSS = –15V to –10V, VREF = 2.5V (internal), and fDATA = 670kSPS in parallel mode or 470kSPS in
serial mode, unless otherwise noted.
ADS8557
PARAMETER
CONDITIONS
TYP (1)
MIN
MAX
UNIT
DC ACCURACY
Resolution
14
No missing codes
Integral linearity error
Differential linearity error
Bits
14
Bits
INL
–1
±0.4
1
LSB
DNL
–1
±0.25
1
LSB
–4
±0.8
4
Offset error
Offset error drift
Gain error
Referenced to voltage at REFIO
Gain error drift
Referenced to voltage at REFIO
±6
ppm/°C
PSRR At output code FFFFh, related to AVDD
60
dB
Power-supply rejection ratio
–0.75
±0.25
mV
µV/°C
±3.5
0.75
%FSR
SAMPLING DYNAMICS
Acquisition time
tACQ
Conversion time per ADC
tCONV
Internal conversion clock period
tCCLK
Throughput rate
fDATA
280
ns
1.19
µs
18.5
tCCLK
64.1
ns
Parallel interface,
internal clock and reference
670
kSPS
Serial interface,
internal clock and reference
470
kSPS
AC ACCURACY
Signal-to-noise ratio
Signal-to-noise ratio + distortion
Total harmonic distortion (2)
SNR At fIN = 10kHz
84
85
SINAD At fIN = 10kHz
83
84
THD At fIN = 10kHz
Spurious-free dynamic range
SFDR At fIN = 10kHz
Channel-to-channel isolation
At fIN = 10kHz
–3dB small-signal bandwidth
(1)
(2)
–91
86
92
dB
dB
–86
dB
dB
100
dB
In 4 × VREF mode
48
MHz
In 2 × VREF mode
24
MHz
All values are at TA = +25°C.
Calculated on the first nine harmonics of the input frequency.
Copyright © 2006–2009, Texas Instruments Incorporated
Product Folder Link(s): ADS8556 ADS8557 ADS8558
5
ADS8556
ADS8557
ADS8558
SBAS404A – OCTOBER 2006 – REVISED AUGUST 2009 ............................................................................................................................................... www.ti.com
ELECTRICAL CHARACTERISTICS: ADS8558
Over recommended operating free-air temperature range of –40°C to +125°C, AVDD = 4.5V to 5V, BVDD = 2.7V to 5.5V,
HVDD = 10V to 15V, HVSS = –15V to –10V, VREF = 2.5V (internal), and fDATA = 730kSPS in parallel mode or 500kSPS in
serial mode, unless otherwise noted.
ADS8558
PARAMETER
CONDITIONS
TYP (1)
MIN
MAX
UNIT
DC ACCURACY
Resolution
12
No missing codes
Integral linearity error
Differential linearity error
Bits
12
Bits
INL
–0.75
±0.2
0.75
LSB
DNL
–0.5
±0.2
0.5
LSB
–4
±0.8
4
Offset error
Offset error drift
Gain error
Referenced to voltage at REFIO
Gain error drift
Referenced to voltage at REFIO
±6
ppm/°C
PSRR At output code FFFFh, related to AVDD
60
dB
Power-supply rejection ratio
–0.75
±0.25
mV
µV/°C
±3.5
0.75
%FSR
SAMPLING DYNAMICS
Acquisition time
tACQ
Conversion time per ADC
tCONV
Internal conversion clock period
tCCLK
Throughput rate
fDATA
280
ns
1.09
µs
18.5
tCCLK
58.8
ns
Parallel interface,
internal clock and reference
730
kSPS
Serial interface,
internal clock and reference
500
kSPS
AC ACCURACY
Signal-to-noise ratio
Signal-to-noise ratio + distortion
Total harmonic distortion (2)
SNR At fIN = 10kHz
73
73.9
SINAD At fIN = 10kHz
73
73.8
THD At fIN = 10kHz
Spurious-free dynamic range
SFDR At fIN = 10kHz
Channel-to-channel isolation
At fIN = 10kHz
–3dB small-signal bandwidth
(1)
(2)
6
–89
84
92
dB
dB
–84
dB
dB
100
dB
In 4 × VREF mode
48
MHz
In 2 × VREF mode
24
MHz
All values are at TA = +25°C.
Calculated on the first nine harmonics of the input frequency.
Copyright © 2006–2009, Texas Instruments Incorporated
Product Folder Link(s): ADS8556 ADS8557 ADS8558
ADS8556
ADS8557
ADS8558
www.ti.com ............................................................................................................................................... SBAS404A – OCTOBER 2006 – REVISED AUGUST 2009
ELECTRICAL CHARACTERISTICS: GENERAL
Over recommended operating free-air temperature range of –40°C to +125°C, AVDD = 4.5V to 5.5V, BVDD = 2.7V to 5.5V,
HVDD = 10V to 15V, HVSS = –15V to –10V, VREF = 2.5V (internal), and fDATA = maximum, unless otherwise noted.
ADS8556, ADS8557, ADS8558
PARAMETER
CONDITIONS
TYP (1)
MIN
MAX
UNIT
ANALOG INPUT
Bipolar full-scale range
CHXX
Input capacitance
Input leakage current
RANGE pin/RANGE bit = 0
–4 × VREF
RANGE pin/RANGE bit = 1
–2 × VREF
+4 × VREF
+2 × VREF
Input range = ±4 × VREF
10
Input range = ±2 × VREF
20
Aperture delay matching
pF
±1
Common CONVST for all channels
Aperture jitter
V
pF
No ongoing conversion
Aperture delay
V
µA
5
ns
250
ps
50
ps
EXTERNAL CLOCK INPUT (XCLK)
External clock frequency
fXCLK An external reference must be used for fXCLK > fCCLK
1
External clock duty cycle
18
45
20
MHz
55
%
REFERENCE VOLTAGE OUTPUT (REFOUT)
Reference voltage
Reference voltage drift
Power-supply rejection ratio
Output current
VREF
2.5V operation, REFDAC = 0x3FF
2.485
2.5
2.515
V
2.5V operation, REFDAC = 0x3FF at +25°C
2.496
2.5
2.504
V
3.0V operation, REFDAC = 0x3FF
2.985
3.0
3.015
V
3.0V operation, REFDAC = 0x3FF at +25°C
2.995
3.0
3.005
dVREF/dT
±10
PSRR
73
IREFOUT DC current
V
ppm/°C
dB
–2
2
mA
Short-circuit current (2)
IREFSC
50
mA
Turn-on settling time
tREFON
10
ms
µF
External load capacitance
Tuning range
At CREF_x pins
4.7
10
At REFIO pins
100
470
REFDAC Internal reference output voltage range
REFDAC resolution
REFDAC differential nonlinearity
nF
0.2 × VREF
VREF
10
V
Bits
DNLDAC
–1
±0.1
1
LSB
REFDAC integral nonlinearity
INLDAC
–2
±0.1
2
LSB
REFDAC offset error
VOSDAC VREF = 0.5V (DAC = 0x0CC)
–4
±0.65
4
LSB
2.5
3.025
REFERENCE VOLTAGE INPUT (REFIN)
Reference input voltage
VREFIN
0.5
Input resistance
100
Input capacitance
V
MΩ
5
pF
Reference input current
1
µA
SERIAL CLOCK INPUT (SCLK)
Serial clock input frequency
fSCLK
0.1
36
MHz
Serial clock period
tSCLK
0.0278
10
µs
40
60
%
Serial clock duty cycle
DIGITAL INPUTS (3)
Logic family
CMOS with Schmitt-Trigger
High-level input voltage
0.7 × BVDD
BVDD + 0.3
V
Low-level input voltage
BGND – 0.3
0.3 × BVDD
V
+50
nA
Input current
VI = BVDD to BGND
Input capacitance
(1)
(2)
(3)
–50
5
pF
All values are at TA = +25°C.
Reference output current is not limited internally.
Specified by design.
Copyright © 2006–2009, Texas Instruments Incorporated
Product Folder Link(s): ADS8556 ADS8557 ADS8558
7
ADS8556
ADS8557
ADS8558
SBAS404A – OCTOBER 2006 – REVISED AUGUST 2009 ............................................................................................................................................... www.ti.com
ELECTRICAL CHARACTERISTICS: GENERAL (continued)
Over recommended operating free-air temperature range of –40°C to +125°C, AVDD = 4.5V to 5.5V, BVDD = 2.7V to 5.5V,
HVDD = 10V to 15V, HVSS = –15V to –10V, VREF = 2.5V (internal), and fDATA = maximum, unless otherwise noted.
ADS8556, ADS8557, ADS8558
PARAMETER
CONDITIONS
TYP (1)
MIN
MAX
UNIT
DIGITAL OUTPUTS (4)
Logic family
CMOS
High-level output voltage
IOH = 100µA
Low-level output voltage
IOH = –100µA
BVDD – 0.6
BVDD
BGND
BGND + 0.4
V
–50
50
nA
High-impedance-state output current
Output capacitance
5
Load capacitance
V
pF
30
pF
POWER-SUPPLY REQUIREMENTS
Analog supply voltage
AVDD
4.5
5.0
5.5
V
Buffer I/O supply voltage
BVDD
2.7
3.0
5.5
V
Input positive supply voltage
HVDD
5.0
10.0
16.5
V
Input negative supply voltage
HVSS
–16.5
–10.0
–5.0
V
fDATA = maximum
30.0
36.0
mA
ADS8556, fDATA = 250kSPS (auto-NAP mode)
14.0
16.5
mA
ADS8557, fDATA = 250kSPS (auto-NAP mode)
14.0
17.0
mA
IAVDD ADS8558, fDATA = 250kSPS (auto-NAP mode)
14.0
18.0
mA
Auto-NAP mode, no ongoing conversion,
internal conversion clock
4.0
6.0
mA
Power-down mode
0.1
50.0
µA
fDATA = maximum
0.9
2.0
mA
0.5
1.5
mA
0.1
10.0
µA
Power-down mode
0.1
10.0
µA
ADS8556, fDATA = maximum
3.0
3.5
mA
ADS8557, fDATA = maximum
3.1
3.6
mA
ADS8558, fDATA = maximum
3.3
4.0
mA
1.6
2.0
mA
Auto-NAP mode, no ongoing conversion,
internal conversion clock
0.2
0.3
µA
Power-down mode
0.1
10.0
µA
ADS8556, fDATA = maximum
3.6
4.0
mA
ADS8557, fDATA = maximum
3.6
4.2
mA
ADS8558, fDATA = maximum
4.0
4.8
mA
1.8
2.2
mA
Auto-NAP mode, no ongoing conversion,
internal conversion clock
0.2
0.25
µA
Power-down mode
0.1
10.0
µA
Analog supply current (5)
Buffer I/O supply current (6)
Input positive supply current (7)
Input negative supply current (8)
(4)
(5)
(6)
(7)
(8)
8
fDATA = 250kSPS (auto-NAP mode)
IBVDD Auto-NAP mode, no ongoing conversion,
internal conversion clock
IHVDD fDATA = 250kSPS (auto-NAP mode)
IHVSS fDATA = 250kSPS (auto-NAP mode)
Specified by design.
At AVDD = 5V.
At BVDD = 3V, parallel mode, load capacitance = 6pF/pin.
At HVDD = 15V.
At HVSS = –15V.
Copyright © 2006–2009, Texas Instruments Incorporated
Product Folder Link(s): ADS8556 ADS8557 ADS8558
ADS8556
ADS8557
ADS8558
www.ti.com ............................................................................................................................................... SBAS404A – OCTOBER 2006 – REVISED AUGUST 2009
ELECTRICAL CHARACTERISTICS: GENERAL (continued)
Over recommended operating free-air temperature range of –40°C to +125°C, AVDD = 4.5V to 5.5V, BVDD = 2.7V to 5.5V,
HVDD = 10V to 15V, HVSS = –15V to –10V, VREF = 2.5V (internal), and fDATA = maximum, unless otherwise noted.
ADS8556, ADS8557, ADS8558
PARAMETER
CONDITIONS
MIN
TYP (1)
MAX
UNIT
POWER-SUPPLY REQUIREMENTS (continued)
Power dissipation (9)
ADS8556, fDATA = maximum
251.7
298.5
mW
ADS8557, fDATA = maximum
253.2
303.0
mW
ADS8558, fDATA = maximum
262.2
318.0
mW
ADS8556, fDATA = 250kSPS (auto-NAP mode)
122.5
150.0
mW
ADS8557, fDATA = 250kSPS (auto-NAP mode)
122.5
152.5
mW
ADS8558, fDATA = 250kSPS (auto-NAP mode)
122.5
157.5
mW
26.0
38.3
mW
3.8
580.0
µW
Auto-NAP mode, no ongoing conversion,
internal conversion clock
Power-down mode
(9)
At AVDD = 5V, BVDD = 3V, HVDD = 15V, and HVSS = –15V.
EQUIVALENT INPUT CIRCUITS
Input range: ±2VREF
RSER = 200W
Input range: ±4VREF
RSW = 130W
RSER = 200W
CH_XX
RSW = 130W
CH_XX
CS = 20pF
CPAR = 5pF
CS = 10pF
VDC
CPAR = 5pF
VDC
CS = 20pF
AGND
CS = 10pF
AGND
RSER = 200W
RSW = 130W
RSER = 200W
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RSW = 130W
9
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ADS8557
ADS8558
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PIN CONFIGURATION
AVDD
AGND
56
REFIO
57
AGND
58
AGND
59
AGND
60
REFC_A
AVDD
61
AGND
PAR/SER
62
REFC_B
HW/SW
63
AGND
REFEN/WR
64
REFC_C
DB15
PM PACKAGE
LQFP-64
(TOP VIEW)
55
54
53
52
51
50
49
DB14/REFBUFEN
1
48 CH_C1
DB13/SDI
2
47 AVDD
DB12
3
46 AVDD
DB11
4
45 CH_C0
DB10/SDO_C
5
44 AGND
DB9/SDO_B
6
43 AGND
DB8/SDO_A
7
BGND
8
BVDD
9
42 CH_B1
ADS8556
ADS8557
ADS8558
41 AVDD
40 AVDD
DB7/HBEN/DCEN 10
10
39 CH_B0
20
21
22
23
24
25
26
27
28
29
30
31
32
HVSS
HVDD
AGND
19
WORD/BYTE
18
RESET
17
RANGE/XCLK
33 CH_A0
AVDD
34 AVDD
DB1/SEL_B 16
AGND
DB2/SEL_C 15
STBY
35 AVDD
CONVST_A
DB3/DCIN_C 14
CONVST_B
36 CH_A1
RD
DB4/DCIN_B 13
CONVST_C
37 AGND
CS/FS
DB5/DCIN_A 12
BUSY/INT
38 AGND
DB0/SEL_A
DB6/SCLK 11
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ADS8558
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TERMINAL FUNCTIONS
DESCRIPTION
NAME
DB14/REFBUFEN
PIN #
1
TYPE (1)
DIO/DI
PARALLEL INTERFACE (PAR/SER = 0)
SERIAL INTERFACE (PAR/SER = 1)
Data bit 14 input/output
Output is '0' for the ADS8557/8
Hardware mode (HW/SW = 0):
Reference buffers enable input.
When low, all reference buffers are enabled (mandatory if
internal reference is used). When high, all reference buffers
are disabled.
Software mode (HW/SW = 1):Connect to BGND or BVDD.
The reference buffers are controlled by bit C24 (REFBUF) in
control register (CR).
DB13/SDI
2
DIO/DI
Data bit 13 input/output
Output is MSB for the ADS8557 and '0' for the
ADS8558
Hardware mode (HW/SW = 0): Connect to BGND
Software mode (HW/SW = 1): Serial data input
DB12
3
DIO
Data bit 12 input/output
Output is '0' for the ADS8558
DB11
4
DIO
Data bit 11 input/output
Output is MSB for the ADS8558
Connect to BGND
DB10/SDO_C
5
DIO/DO
Data bit 10 input/output
When SEL_C = 1, data output for channel C
When SEL_C = 0, this pin should be tied to BGND
DB9/SDO_B
6
DIO/DO
Data bit 9 input/output
When SEL_B = 1, data output for channel B
When SEL_B = 0, this pin should be tied to BGND
When SEL_C = 0, data from channel C1 are also available
on this output
Data bit 8 input/output
Data output for channel A
When SEL_C = 0, data from channel C0 are also available
on this output
When SEL_C = 0 and SEL_B = 0, SDO_A acts as the single
data output for all channels
Connect to BGND
DB8/SDO_A
7
DIO/DO
BGND
8
P
Buffer IO ground, connect to digital ground plane
BVDD
9
P
Buffer IO supply, connect to digital supply (2.7V to 5.5V). Decouple with a 1µF ceramic capacitor or a combination
of 100nF and 10µF ceramic capacitors to BGND.
Word mode (WORD/BYTE = 0):
Data bit 7 input/output
DB7/HBEN/DCEN
10
DIO/DI/DI
DB6/SCLK
11
DIO/DI
DB5/DCIN_A
12
DIO/DI
DB4/DCIN_B
13
DIO/DI
DB3/DCIN_C
14
DIO/DI
DB2/SEL_C
DB1/SEL_B
(1)
15
16
DIO/DI
DIO/DI
Byte mode (WORD/BYTE = 1):
High byte enable input.
When high, the high byte is output first on
DB[15:8]. When low, the low byte is output first on
DB[15:8].
Word mode (WORD/BYTE = 0):
Data bit 6 input/output
Byte mode (WORD/BYTE = 1):
Connect to BGND or BVDD
Word mode (WORD/BYTE = 0):
Data bit 5 input/output
Byte mode (WORD/BYTE = 1):
Connect to BGND or BVDD
Word mode (WORD/BYTE = 0):
Data bit 4 input/output
Byte mode (WORD/BYTE = 1):
Connect to BGND or BVDD
Word mode (WORD/BYTE = 0):
Data bit 3 input/output
Byte mode (WORD/BYTE = 1):
Connect to BGND or BVDD
Word mode (WORD/BYTE = 0):
Data bit 2 input/output
Byte mode (WORD/BYTE = 1):
Connect to BGND or BVDD
Word mode (WORD/BYTE = 0):
Data bit 1 input/output
Byte mode (WORD/BYTE = 1):
Connect to BGND or BVDD
Daisy-chain enable input.
When high, DB[5:3] serve as daisy-chain inputs DCIN[A:C].
If daisy-chain mode is not used, connect to BGND.
Serial interface clock input (36MHz max)
When DCEN = 1, daisy-chain data input for channel A
When DCEN = 0, connect to BGND
When SEL_B = 1 and DCEN = 1, daisy-chain data input for
channel B
When DCEN = 0, connect to BGND
When SEL_C = 1 and DCEN = 1, daisy-chain data input for
channel C
When DCEN = 0, connect to BGND
Select SDO_C input.
When high, SDO_C is active. When low, SDO_C is disabled.
Select SDO_B input.
When high, SDO_B is active. When low, SDO_B is disabled.
AI = analog input; AIO = analog input/output; DI = digital input; DO = digital output; DIO = digital input/output; and P = power supply.
Copyright © 2006–2009, Texas Instruments Incorporated
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TERMINAL FUNCTIONS (continued)
DESCRIPTION
NAME
DB0/SEL_A
PIN #
17
TYPE (1)
DIO/DI
BUSY/INT
18
DO
CS/FS
19
DI/DI
RD
20
DI
CONVST_C
21
DI
PARALLEL INTERFACE (PAR/SER = 0)
Word mode (WORD/BYTE = 0):
Data bit 0 (LSB) input/output
Byte mode (WORD/BYTE = 1):
Connect to BGND or BVDD
SERIAL INTERFACE (PAR/SER = 1)
Select SDO_A input.
When high, SDO_A is active. When low, SDO_A is disabled.
Should always be high.
When CR bit C21 = 0 (BUSY/INT), converter busy status output. Transitions high when a conversion has been
started and remains high during the entire process. Transitions low when the conversion data of all six channels
are latched to the output register and remains low thereafter.
In sequential mode (SEQ = 1 in the CR), the BUSY output transitions high when a conversion has been started
and goes low for a single conversion clock cycle (tCCLK) whenever a channel pair conversion is completed.
When bit C21 = 1 (BUSY/INT in CR), interrupt output. This bit transitions high after a conversion has been
completed and remains high until the conversion result has been read.
The polarity of BUSY/INT output can be changed using bit C20 (BUSY L/H) in the control register.
Chip select input.
When low, the parallel interface is enabled. When
high, the interface is disabled.
Frame synchronization.
The falling edge of FS controls the frame transfer.
Read data input.
When low, the parallel data output is enabled.
When high, the data output is disabled.
Connect to BGND
Hardware mode (HW/SW = 0): Conversion start of channel pair C.
The rising edge of this signal initiates simultaneous conversion of analog signals at inputs CH_C[1:0]. CONVST_C
should remain high during the entire conversion cycle, otherwise both ADCs of channel C are put in partial
power-down mode (see the Reset and Power-down Modes sections).
Software mode (HW/SW = 1): Conversion start of channel pair C in sequential mode (CR bit C23 = 1) only;
connect to BGND or BVDD otherwise
CONVST_B
22
DI
Hardware mode (HW/SW = 0): Conversion start of channel pair B.
The rising edge of this signal initiates simultaneous conversion of analog signals at inputs CH_B[1:0]. CONVST_B
should remain high during the entire conversion cycle; otherwise, both ADCs of channel B are put into partial
power-down mode (see the Reset and Power-down Modes sections).
Software mode (HW/SW = 1): Conversion start of channel pair B in sequential mode (CR bit C23 = 1) only;
connect to BGND or BVDD otherwise
CONVST_A
23
DI
Hardware mode (HW/SW = 0): Conversion start of channel pair A.
The rising edge of this signal initiates simultaneous conversion of analog signals at inputs CH_A[1:0]. CONVST_A
should remain high during the entire conversion cycle; otherwise, both ADCs of channel A are put into partial
power-down mode (see the Reset and Power-down Modes sections).
Software mode (HW/SW = 1): Conversion start of all selected channels except in sequential mode
(CR bit C23 = 1): Conversion start of channel pair A only
12
STBY
24
DI
Standby mode input. When low, the entire device is powered-down (including the internal clock and reference).
When high, the device operates in normal mode.
AGND
25, 32,
37, 38,
43, 44,
49, 52,
53, 55,
57, 59
P
Analog ground, connect to analog ground plane
Pin 25 may have a dedicated ground if the difference between its potential and AGND is always kept within
±300mV.
AVDD
26, 34,
35, 40,
41, 46,
47, 50,
60
P
Analog power supply (4.5V to 5.5V). Decouple each pin with a 100nF ceramic capacitor to AGND. Use an
additional 10µF capacitor to AGND close to the device but without compromising the placement of the smaller
capacitor. Pin 26 may have a dedicated power supply if the difference between its potential and AVDD is always
kept within ±300mV.
Hardware mode (HW/SW = 0): Input voltage range select input.
When low, the analog input range is ±4VREF. When high, the analog input range is ±2VREF.
RANGE/XCLK
27
DI/DIO
RESET
28
DI
Reset input, active high. Aborts any ongoing conversions. Resets the internal control register to 0x000003FF. The
RESET pulse should be at least 50ns long.
Software mode (HW/SW = 1): External conversion clock input, if CR bit C11 (CLKSEL) is set high or internal
conversion clock output, if CR bit C10 (CLKOUT_EN) is set high. If not used, connect to BVDD or BGND.
WORD/BYTE
29
DI
Output mode selection input.
When low, data are transferred in word mode using
DB[15:0]. When high, data are transferred in byte
Connect to BGND
mode using DB[15:8] with the byte order controlled
by HBEN pin while two accesses are required for a
complete 16-bit transfer.
HVSS
30
P
Negative supply voltage for the analog inputs (–16.5V to –5V).
Decouple with a 100nF ceramic capacitor to AGND placed next to the device and a 10µF capacitor to AGND close
to the device but without compromising the placement of the smaller capacitor.
Copyright © 2006–2009, Texas Instruments Incorporated
Product Folder Link(s): ADS8556 ADS8557 ADS8558
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ADS8557
ADS8558
www.ti.com ............................................................................................................................................... SBAS404A – OCTOBER 2006 – REVISED AUGUST 2009
TERMINAL FUNCTIONS (continued)
DESCRIPTION
NAME
PIN #
TYPE (1)
PARALLEL INTERFACE (PAR/SER = 0)
SERIAL INTERFACE (PAR/SER = 1)
HVDD
31
P
Positive supply voltage for the analog inputs (5V to 16.5V). Decouple with a 100nF ceramic capacitor to AGND
placed next to the device and a 10µF capacitor to AGND close to the device but without compromising the
placement of the smaller capacitor.
CH_A0
33
AI
Analog input of channel A0. The input voltage range is controlled by RANGE pin in hardware mode or CR bit C26
(RANGE_A) in software mode.
CH_A1
36
AI
Analog input of channel A1. The input voltage range is controlled by RANGE pin in hardware mode or CR bit C26
(RANGE_A) in software mode.
CH_B0
39
AI
Analog input of channel B0. The input voltage range is controlled by RANGE pin in hardware mode or CR bit C27
(RANGE_B) in software mode.
CH_B1
42
AI
Analog input of channel B1. The input voltage range is controlled by RANGE pin in hardware mode or CR bit C27
(RANGE_B) in software mode.
CH_C0
45
AI
Analog input of channel C0. The input voltage range is controlled by RANGE pin in hardware mode or CR bit C28
(RANGE_C) in software mode.
CH_C1
48
AI
Analog input of channel C1. The input voltage range is controlled by RANGE pin in hardware mode or CR bit C28
(RANGE_C) in software mode.
REFIO
51
AIO
Reference voltage input/output (0.5V to 3.025V).
The internal reference is enabled via REFEN/WR pin in hardware mode or CR bit C25 (REFEN) in software mode.
The output value is controlled by the internal DAC (CR bits C[9:0]). Connect a 470nF ceramic decoupling
capacitor between this pin and pin 52.
REFC_A
54
AI
Decoupling capacitor for reference of channels A.
Connect a 10µF ceramic decoupling capacitor between this pin and pin 53.
REFC_B
56
AI
Decoupling capacitor for reference of channels B.
Connect a 10µF ceramic decoupling capacitor between this pin and pin 55.
REFC_C
58
AI
Decoupling capacitor for reference of channels C.
Connect a 10µF ceramic decoupling capacitor between this pin and pin 57.
PAR/SER
61
DI
Interface mode selection input.
When low, the parallel interface is selected. When high, the serial interface is enabled.
HW/SW
62
DI
Mode selection input.
When low, the hardware mode is selected and part works according to the settings of external pins. When high,
the software mode is selected in which the device is configured by writing into the control register.
REFEN/WR
DB15
63
64
DI
DIO
Hardware mode (HW/SW = 0):
Internal reference enable input.
When high, the internal reference is enabled (the
reference buffers are to be enabled). When low,
the internal reference is disabled and an external
reference is applied at REFIO.
Hardware mode (HW/SW = 0):
Internal reference enable input.
When high, the internal reference is enabled (the reference
buffers are to be enabled). When low, the internal reference
is disabled and an external reference should be applied at
REFIO.
Software mode (HW/SW = 1): Write input.
The parallel data input is enabled, when CS and
WR are low. The internal reference is enabled by
the CR bit C25 (REFEN).
Software mode (HW/SW = 1): Connect to BGND or BVDD.
The internal reference is enabled by CR bit C25 (REFEN).
Data bit 15 (MSB) input/output
Output is '0' for the ADS8557/8
Connect to BGND
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TIMING CHARACTERISTICS
t1
CONVST_x
tACQ
tCONV
tD1
BUSY
(C20 = C21 = 0)
t3
t2
FS
tSCLK
32
1
SCLK
tD4
tD3
tD2
ADS8556
SDO_x
CH_x0
MSB
tH2
CH_x1
D3
tS1
SDI or
DCIN_x
Don’t Care
D31
D3
CH_x1
D2
tH1
CH_x1
D1
CH_x1
LSB
D2
D1
D0
Don’t
Care
Figure 1. Serial Operation Timing Diagram (All Three SDOs Active)
Serial Interface Timing Requirements (1)
Over recommended operating free-air temperature range at –40°C to +125°C, AVDD = 5V, and BVDD = 2.7V to 5.5V, unless
otherwise noted.
TEST
CONDITION
PARAMETER
tACQ
Acquisition time
tCONV
Conversion time
ADS8556, ADS8557, ADS8558
MIN
TYP
MAX
280
t1
CONVST_x low time
t2
BUSY low to FS low time
UNIT
ns
ADS8556
1.26
ns
ADS8557
1.19
ns
ADS8558
1.09
ns
20
ns
0
ns
ADS8556
40
ns
ADS8557
20
ns
ADS8558
0
t3
Bus access finished to next conversion
start time
tD1
CONVST_x high to BUSY high delay
5
20
ns
tD2
FS low to SDO_x active delay
5
12
ns
tD3
SCLK rising edge to new data valid delay
15
ns
tD4
FS high to SDO_x 3-state delay
10
ns
tH1
Input data to SCLK falling edge hold time
5
ns
tH2
Output data to SCLK rising edge hold time
5
ns
tS1
Input data to SCLK falling edge setup time
tSCLK
Serial clock period
(1)
14
ns
3
0.0278
ns
10
µs
All input signals are specified with tR = tF = 1.5ns (10% to 90% of BVDD) and timed from a voltage level of (VIL + VIH)/2.
Copyright © 2006–2009, Texas Instruments Incorporated
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ADS8558
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t1
CONVST_A
CONVST_B
CONVST_C
tCONV
tACQ
tD1
BUSY
(C20 = C21 = 0)
t3
t2
CS
t4
t6
t5
t7
RD
tD5
tD5
CH
A0
DB[15:0]
CH
A1
CH
B0
tH3
CH
C0
CH
B1
CH
C1
Figure 2. Parallel Read Access Timing Diagram
Parallel Interface Timing Requirements (Read Access) (1)
Over recommended operating free-air temperature range at –40°C to +125°C, AVDD = 5V, and BVDD = 2.7V to 5.5V, unless
otherwise noted.
TEST
CONDITION
PARAMETER
tACQ
tCONV
Acquisition time
ADS8556, ADS8557, ADS8558
MIN
TYP
MAX
280
Conversion time
t1
CONVST_x low time
t2
BUSY low to CS low time
UNIT
ns
ADS8556
1.26
ns
ADS8557
1.19
ns
ADS8558
1.09
ns
20
ns
0
ns
ADS8556
40
ns
ADS8557
20
ns
ADS8558
t3
Bus access finished to next conversion
start time (2)
0
ns
t4
CS low to RD low time
0
ns
t5
RD high to CS high time
0
ns
t6
RD pulse width
30
ns
t7
Minimum time between two read accesses
10
tD1
CONVST_x high to BUSY high delay
tD5
RD falling edge to output data valid delay
tH3
Output data to RD rising edge hold time
(1)
(2)
5
ns
20
ns
20
ns
5
ns
All input signals are specified with tR = tF = 1.5ns (10% to 90% of BVDD) and timed from a voltage level of (VIL + VIH)/2.
Refer to CS signal or RD, whichever occurs first.
Copyright © 2006–2009, Texas Instruments Incorporated
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ADS8557
ADS8558
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CS
t9
t10
t11
t8
WR
tS2
tH4
C
[31:16]
DB[15:0]
C
[15:0]
Don’t
Care
Word Mode
(WORD/BYTE = 0)
C
[31:24]
C
[15:8]
C
[23:16]
C
[7:0]
Byte Mode
(WORD/BYTE = 1)
Figure 3. Parallel Write Access Timing Diagram
Parallel Interface Timing Requirements (Write Access) (1)
Over recommended operating free-air temperature range at –40°C to +125°C, AVDD = 5V, and BVDD = 2.7V to 5.5V, unless
otherwise noted.
ADS8556, ADS8557, ADS8558
PARAMETER
MIN
t8
CS low to WR low time
t9
t10
t11
TYP
MAX
UNIT
0
ns
WR low pulse width
15
ns
WR high pulse width
10
ns
WR high to CS high time
0
ns
tS2
Output data to WR rising edge setup time
5
ns
tH4
Data output to WR rising edge hold time
5
ns
(1)
16
All input signals are specified with tR = tF = 1.5ns (10% to 90% of BVDD) and timed from a voltage level of (VIL + VIH)/2.
Copyright © 2006–2009, Texas Instruments Incorporated
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ADS8558
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TYPICAL CHARACTERISTICS
At +25°C, over entire supply voltage range, VREF = 2.5V (internal), and fDATA = maximum, unless otherwise noted.
INL vs CODE
(ADS8556 ±10VIN Range)
3.0
2.0
1.5
1.0
0.5
0
-0.5
-1.0
-1.5
-2.0
-2.5
1.5
1.0
0.5
0
-0.5
-1.0
-1.5
-2.0
-3.0
0
1.5
8190 16380 24570 32760 40950 49140 57330 65520
8190 16380 24570 32760 40950 49140 57330 65520
Code
Figure 4.
Figure 5.
DNL vs CODE
(ADS8556 ±10VIN Range)
DNL vs CODE
(ADS8556 ±5VIN Range)
1.5
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
fDATA = Max
Internal Reference
1.0
0
Code
Differential Nonlinearity (LSB)
Differential Nonlinearity (LSB)
2.0
-2.5
-3.0
0.5
0
-0.5
-1.0
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
fDATA = Max
Internal Reference
1.0
0.5
0
-0.5
-1.0
0
1.0
8190 16380 24570 32760 40950 49140 57330 65520
0.4
8190 16380 24570 32760 40950 49140 57330 65520
Code
Figure 6.
Figure 7.
INL vs CODE
(ADS8557 ±10VIN Range)
INL vs CODE
(ADS8557 ±5VIN Range)
1.0
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
fDATA = Max
Internal Reference
0.8
Integral Nonlinearity (LSB)
0.6
0
Code
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
fDATA = Max
Internal Reference
0.8
Integral Nonlinearity (LSB)
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
fDATA = Max
Internal Reference
2.5
Integral Nonlinearity (LSB)
Integral Nonlinearity (LSB)
3.0
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
fDATA = Max
Internal Reference
2.5
INL vs CODE
(ADS8556 ±5VIN Range)
0.2
0
-0.2
-0.4
-0.6
-0.8
0.6
0.4
0.2
0
-0.2
-0.4
-0.6
-0.8
-1.0
-1.0
0
2000
4000
6000
8000 10000 12000 14000 16000
0
2000
4000
6000
8000 10000 12000 14000 16000
Code
Code
Figure 8.
Figure 9.
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TYPICAL CHARACTERISTICS (continued)
At +25°C, over entire supply voltage range, VREF = 2.5V (internal), and fDATA = maximum, unless otherwise noted.
DNL vs CODE
(ADS8557 ±10VIN Range)
1.0
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
fDATA = Max
Internal Reference
0.8
0.6
0.4
Differential Nonlinearity (LSB)
Differential Nonlinearity (LSB)
1.0
DNL vs CODE
(ADS8557 ±5VIN Range)
0.2
0
-0.2
-0.4
-0.6
-0.8
0.6
0.4
0.2
0
-0.2
-0.4
-0.6
-0.8
-1.0
-1.0
0
2000
0.75
4000
6000
8000 10000 12000 14000 16000
0.25
2000
4000
6000
8000 10000 12000 14000 16000
Code
Figure 10.
Figure 11.
INL vs CODE
(ADS8558)
DNL vs CODE
(ADS8558)
0.5
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
fDATA = Max
Internal Reference
0.50
0
Code
Differential Nonlinearity (LSB)
Integral Nonlinearity (LSB)
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
fDATA = Max
Internal Reference
0.8
0
-0.25
-0.50
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
fDATA = Max
Internal Reference
0.4
0.3
0.2
0.1
0
-0.1
-0.2
-0.3
-0.4
-0.75
-0.5
0
500
1000
1500
2000
2500
3000
3500
4000
0
500
1000
1500
Code
2000
2500
3000
3500
4000
Code
Figure 12.
Figure 13.
OFFSET ERROR vs TEMPERATURE
GAIN ERROR vs TEMPERATURE
4
0.75
3
0.50
Gain Error (%)
Offset Error (mV)
2
1
0
-1
0.25
0
-0.25
-2
-0.50
-3
-0.75
-4
-40 -25 -10
5
20
35
50
65
80
95
110 125
-40 -25 -10
Temperature (°C)
20
35
50
65
80
95
110 125
Temperature (°C)
Figure 14.
18
5
Figure 15.
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TYPICAL CHARACTERISTICS (continued)
At +25°C, over entire supply voltage range, VREF = 2.5V (internal), and fDATA = maximum, unless otherwise noted.
PSRR vs AVDD NOISE FREQUENCY
CONVERSION TIME vs TEMPERATURE
1.40
CSUPPLY = 100nF on AVDD
1.35
-40
Conversion Time (ms)
Power-Supply Rejection Ratio (dB)
-30
-50
-60
-70
1.30
1.25
ADS8556
1.20
ADS8557
1.15
1.10
1.05
ADS8558
1.00
-80
0.95
-90
0.90
0
20
40
60
80
100 120 140 160 180
200
4500
4000
3500
3000
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
8192 Samples
Range = +4 ´ VREF
Internal Reference
T = +25°C
92
1000
110 125
88
ADS8557
86
84
AVDD = BVDD = 5V
HVSS = -15V, HVDD = 15V
fSIGNAL = 10kHz, fDATA = Max
Range = ±4 ´ VREF
Internal Reference
82
80
78
76
74
ADS8558
70
-3
-2
0
-1
1
-40 -25 -10
2
5
20
Figure 18.
SINAD vs TEMPERATURE
65
80
95
110 125
THD vs TEMPERATURE
-86
92
90
Total Harmonic Distortion (dB)
ADS8556
88
ADS8557
84
50
Figure 19.
94
86
35
Temperature (°C)
Code
Signal-to-Noise Ratio and Distortion (dB)
95
ADS8556
90
72
500
76
80
SNR vs TEMPERATURE
1500
78
65
94
2000
80
50
Figure 17.
2500
82
35
Figure 16.
Signal-to-Noise Ratio (dB)
Number of Occurrences
5000
20
Temperature (°C)
CODE HISTOGRAM
(8192 Hits)
5500
5
-40 -25 -10
AVDD Noise Frequency (kHz)
AVDD = BVDD = 5V
HVSS = -15V, HVDD = 15V
fSIGNAL = 10kHz, fDATA = Max
Range = ±4 ´ VREF
Internal Reference
74
ADS8558
72
-88
AVDD = BVDD = 5V, HVSS = -15V, HVDD = 15V
fSIGNAL = 10kHz, fDATA = Max, Range = ±4 ´ VREF
Internal Reference
ADS8558
-90
ADS8557
-92
-94
ADS8556
-96
-98
70
-40 -25 -10
5
20
35
50
65
80
95
110 125
-40 -25 -10
5
20
35
50
65
Temperature (°C)
Temperature (°C)
Figure 20.
Figure 21.
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95
110 125
19
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TYPICAL CHARACTERISTICS (continued)
At +25°C, over entire supply voltage range, VREF = 2.5V (internal), and fDATA = maximum, unless otherwise noted.
FREQUENCY SPECTRUM
(2048-Point FFT, fIN = 10kHz, ±10VIN Range)
100
0
98
-20
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
fSAMPLE = 500kSPS
fSIGNAL = 10kHz
Range = ±4 ´ VREF
Internal Reference
T = +25°C
-40
96
Amplitude (dB)
Spurious-Free Dynamic Range (dB)
SFDR vs TEMPERATURE
ADS8556
94
ADS8557
92
AVDD = BVDD = 5V
HVSS = -15V, HVDD = 15V
fSIGNAL = 10kHz, fDATA = Max
Range = ±4 ´ VREF
Internal Reference
90
ADS8558
88
86
-60
-80
-100
-120
-140
-160
-180
-40 -25 -10
5
20
35
50
65
80
95
0
110 125
25
50
75
Figure 22.
Figure 23.
FREQUENCY SPECTRUM
(2048-Point FFT, fIN = 10kHz, ±5VIN Range)
CHANNEL-TO-CHANNEL ISOLATION vs
INPUT NOISE FREQUENCY
0
-60
-80
110
-100
-120
105
100
95
90
-140
85
-160
80
-180
0
25
50
75
100 125 150 175 200 225
250
0
30
60
90
Frequency (kHz)
120 150 180 210 240 270
300
Noise Frequency (kHz)
Figure 24.
Figure 25.
INTERNAL REFERENCE VOLTAGE vs
ANALOG SUPPLY VOLTAGE (2.5V Mode)
INTERNAL REFERENCE VOLTAGE vs TEMPERATURE
(2.5V Mode)
2.504
2.504
2.503
2.503
2.502
2.502
2.501
VREF (V)
VREF (V)
250
AVDD = BVDD = 5V
HVSS = -15V
HVDD = 15V
fDATA = Max
Range = ±2 ´ VREF
Internal Reference
115
Isolation (dB)
-40
Amplitude (dB)
120
AVDD = BVDD = 5V
HVSS = -15V, HVDD = 15V
fSAMPLE = 500kSPS
fSIGNAL = 10kHz
Range = ±2 ´ VREF
Internal Reference
T = +25°C
-20
VREF
2.500
2.501
2.500
2.499
2.499
2.498
2.498
2.497
2.497
2.496
2.496
4.5
4.6
4.7
4.8
4.9
5.0
5.1
5.2
5.3
5.4
5.5
-40 -25 -10
5
20
35
50
65
80
95
110 125
Temperature (°C)
AVDD (V)
Figure 26.
20
100 125 150 175 200 225
Frequency (kHz)
Temperature (°C)
Figure 27.
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TYPICAL CHARACTERISTICS (continued)
At +25°C, over entire supply voltage range, VREF = 2.5V (internal), and fDATA = maximum, unless otherwise noted.
INTERNAL REFERENCE VOLTAGE vs TEMPERATURE
(3.0V Mode)
ANALOG SUPPLY CURRENT vs TEMPERATURE
3.005
3.004
3.003
IAVDD (mA)
VREF (V)
3.002
3.001
3.000
2.999
2.998
2.997
2.996
2.995
-40 -25 -10
5
20
35
50
65
80
95
110 125
36
34
32
30
28
26
24
22
20
18
16
14
12
10
fDATA = Max
AVDD = 5V
Internal Reference
fDATA = 250kSPS (A-NAP)
-40 -25 -10
5
20
Temperature (°C)
Figure 28.
IBVDD (mA)
IAVDD (mA)
AVDD = 5V
Internal Reference
A-NAP Mode
BVDD = 5V
1.4
1.2
fDATA = Max
1.0
0.8
0.6
fDATA = 250kSPS (A-NAP)
0.4
0.2
45 90 135 180 225 270 315 360 405 450 495 540 585 630
-40 -25 -10
5
20
50
65
80
95
110 125
Figure 31.
ADS8556
INPUT SUPPLY CURRENT vs TEMPERATURE
ADS8556
INPUT SUPPLY CURRENT vs INPUT SUPPLY VOLTAGE
4.5
IHVSS (fDATA = Max)
4.0
IHVDD (fDATA = Max)
HVSS = -15V
HVDD = 15V
Range = ±4 ´ VREF
Internal Reference
2.50
2.25
IHVSS (250kSPS A-NAP)
1.75
IHVDD (250kSPS A-NAP)
Input Supply Current (mA)
Input Supply Current (mA)
35
Temperature (°C)
Figure 30.
2.75
1.50
110 125
1.6
3.50
2.00
95
1.8
4.00
3.00
80
Normal Operation
Sample Rate (kSPS)
3.25
65
BUFFER I/O SUPPLY CURRENT vs TEMPERATURE
2.0
0
3.75
50
Figure 29.
ADS8556
ANALOG SUPPLY CURRENT vs DATA RATE
36
34
32
30
28
26
24
22
20
18
16
14
12
10
8
6
4
2
35
Temperature (°C)
IHVSS (fDATA = Max)
3.5
3.0
IHVDD (fDATA = Max)
2.5
2.0
1.5
1.0
IHVSS (250kSPS A-NAP)
0.5
1.25
IHVDD (250kSPS A-NAP)
0
1.00
-40 -25 -10
5
20
35
50
65
80
95
110 125
5
6
7
8
9
10
11
Temperature (°C)
HVDD, |HVSS| (V)
Figure 32.
Figure 33.
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13
14
15
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TYPICAL CHARACTERISTICS (continued)
At +25°C, over entire supply voltage range, VREF = 2.5V (internal), and fDATA = maximum, unless otherwise noted.
ADS8556
INPUT SUPPLY CURRENT vs DATA RATE
3.6
IHVSS
3.3
3.0
IHVSS (A-NAP)
IHVxx (mA)
2.7
2.4
2.1
IHVDD (A-NAP)
1.8
1.5
IHVDD
1.2
0.9
HVSS = -15V
HVDD = 15V
Range = ±4 ´ VREF
0.6
0.3
0
0
90
180
270
360
450
540
630
Data Rate (kSPS)
Figure 34.
22
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GENERAL DESCRIPTION
The ADS8556/7/8 series include six 16-, 14-, and
12-bit
analog-to-digital
converters
(ADCs)
respectively that operate based on the successive
approximation register (SAR) principle. The
architecture is designed on the charge redistribution
principle,
which
inherently
includes
a
sample-and-hold function. The six analog inputs are
grouped into three channel pairs. These channel
pairs can be sampled and converted simultaneously,
preserving the relative phase information of the
signals of each pair. Separate conversion start
signals allow simultaneous sampling on each channel
pair: on four channels or on all six channels.
These devices accept single-ended, bipolar analog
input signals in the selectable ranges of ±4VREF or
±2VREF with an absolute value of up to ±12V; see the
Analog Inputs section.
The devices offer an internal 2.5V/3V reference
source followed by a 10-bit digital-to-analog converter
(DAC) that allows the reference voltage VREF to be
adjusted in 2.44mV or 2.93mV steps, respectively.
The ADS8556/7/8 also offer a selectable parallel or
serial interface that can be used in hardware or
software mode; see the Device Configuration section
for details.
ANALOG
This section addresses the analog input circuit, the
ADCs and control signals, and the reference design
of the device.
Analog Inputs
The inputs and the converters are of single-ended,
bipolar type. The absolute voltage range can be
selected using the RANGE pin (in hardware mode) or
RANGE_x bits (in software mode) in the control
register (CR) to either ±4VREF or ±2VREF. With the
reference set to 2.5V (CR bit C18 = 0), the input
voltage range can be ±10V or ±5V. With the
reference source set to 3V (CR bit C18 = 1), an input
voltage range of ±12V or ±6V can be configured. The
logic state of the RANGE pin is latched with the
falling edge of BUSY (if CR bit C20 = 0).
The input current on the analog inputs depends on
the actual sample rate, input voltage, and signal
source impedance. Essentially, the current into the
analog inputs charges the internal capacitor array
only during the sampling period (tACQ). The source of
the analog input voltage must be able to charge the
input capacitance of 10pF in ±4VREF mode or 20pF in
±2VREF to a 12-, 14-, 16-bit accuracy level within the
acquisition time of 280ns at maximum data rate; see
the Equivalent Input Circuit. During the conversion
period, there is no further input current flow and the
input impedance is greater than 1MΩ. To ensure a
defined start condition, the sampling capacitors of the
ADS8556/7/8 are pre-charged to a fixed internal
voltage, before switching into sampling mode.
To maintain the linearity of the converter, the inputs
should always remain within the specified range of
HVSS – 0.2V to HVDD + 0.2V.
The minimum –3dB bandwidth of the driving
operational amplifier can be calculated using
Equation 1:
ln(2) ´ (n + 1)
f-3dB =
2p ´ tACQ
(1)
where:
n = 16, 14, or 12; n is the resolution of the
ADS8556/7/8
With a minimum acquisition time of tACQ = 280ns, the
required minimum bandwidth of the driving amplifier
is 6.7MHz for the ADS8556, 6MHz for the ADS8557,
or 5.2MHz for the ADS8558. The required bandwidth
can be lower if the application allows a longer
acquisition time. A gain error occurs if a given
application does not fulfill the bandwidth requirement
shown in Equation 1.
A driving operational amplifier may not be required, if
the impedance of the signal source (RSOURCE) fulfills
the requirement of Equation 2:
tACQ
RSOURCE <
- (RSER + RSW)
CS ln(2) ´ (n + 1)
(2)
where:
n = 16, 14, or 12; n is the resolution of the ADC,
CS = 10pF is the sample capacitor value for VIN =
±4 × VREF mode,
RSER = 200Ω is the input resistor value,
and RSW = 130Ω is the switch resistance value
With tACQ = 280ns, the maximum source impedance
should be less than 2.0kΩ for the ADS8556, 2.3kΩ
for the ADS8557, and 2.7kΩ for the ADS8558 in VIN
= ±4VREF mode or less than 0.8kΩ for the ADS8556,
1.0kΩ for the ADS8557, and 1.2kΩ for the ADS8558
in VIN = ±2VREF mode. The source impedance can be
higher if the application allows longer acquisition time.
Analog-to-Digital Converter (ADC)
The devices include six ADCs that operate with either
an internal or an external conversion clock. The
conversion time can be as low as 1.09µs with internal
conversion clock (ADS8558). When an external clock
and reference are used, the minimum conversion
time is 925ns.
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Conversion Clock
The device uses either an internally-generated or an
external (XCLK) conversion clock signal (in software
mode only). In default mode, the device generates an
internal clock. When the CLKSEL bit is set high (bit
C11 in the CR), an external conversion clock of up to
20MHz (max) can be applied on pin 27. In both
cases, 18.5 clock cycles are required for a complete
conversion including the pre-charging of the sample
capacitors. The external clock can remain low
between conversions.
The conversion clock duty cycle should be 50%.
However, the ADS8556/7/8 function properly with a
duty cycle between 45% and 55%.
remain high during the entire conversion cycle; this is
while the BUSY signal remains active. A falling edge
during an ongoing conversion puts the related ADC
pair into partial power-down mode (see the Reset and
Power-Down Modes section for more details).
A conversion start must not be issued during an
ongoing conversion on the same channel pair. It is
allowed to initiate conversions on the other input
pairs, however (see the Sequential Mode section for
more details).
If a parallel interface is used, the behavior of the
output port depends on which CONVST_x signals
have been issued. Figure 35 shows examples of
different scenarios.
CONVST_x
The analog inputs of each channel pair (CH_x0/1) are
held with the rising edge of the corresponding
CONVST_x signal. Only in software mode (except
sequential mode), CONVST_A is used for all six
ADCs. The conversion automatically starts with the
next edge of the conversion clock. CONVST_x should
BUSY
(C20 = C21 = 0)
CS
CONVST_A
CONVST_C
CONVST_B
RD
DB[15:0]
CH
A0
CH
A1
CH
C0
CH
C1
CH
A0
CH
A1
CH
C0
CH
B0
CH
B1
CH
B0
CH
B1
CH
B0
CH
B1
CH
B0
CONVST_B
CONVST_A
CONVST_B
RD
DB[15:0]
NOTE: Boxed areas indicate the minimum required frame to acquire all data.
Figure 35. Data Output versus CONVST_x
24
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BUSY/INT
The BUSY signal indicates if a conversion is in
progress. It goes high with a rising edge of any
CONVST_x signal and goes low when the output
data of the last channel pair are available in the
respective output register. The readout of the data
can be initiated immediately after the falling edge of
BUSY. A falling edge of a CONVST_x input during an
ongoing conversion (when BUSY is high) powers
down the corresponding ADC pair.
In sequential mode, the BUSY signal goes low only
for one clock cycle. See the Sequential Mode section
for more details.
The polarity of the BUSY/INT signal can be changed
using CR bit C20.
Reference
The ADS8556/7/8 provides an internal, low-drift 2.5V
reference source. To increase the input voltage
range, the reference voltage can be switched to 3V
mode using the VREF bit (bit C18 in the CR). The
reference feeds a 10-bit string-DAC controlled by bits
C[9:0] in the control register. The buffered DAC
output is connected to the REFIO pin. In this way, the
voltage at this pin is programmable in 2.44mV
(2.92mV in 3V mode) steps and adjustable to the
application needs without additional external
components. The actual output voltage can be
calculated using Equation 3:
Range ´ (Code + 1)
VREF =
1024
(3)
where:
Range = the chosen maximum reference voltage
output range (2.5V or 3V),
Code = the decimal value of the DAC register
content
Table 1 lists some examples of internal reference
DAC settings with a reference range set to 2.5V.
However, to ensure proper performance, the DAC
output voltage should not be programmed below
0.5V.
The buffered output of the DAC should be decoupled
with a 100nF capacitor (minimum); for best
performance, a 470nF capacitor is recommended. If
the internal reference is placed into power-down
(default), an external reference voltage can drive the
REFIO pin.
The voltage at the REFIO pin is buffered with three
internal amplifiers, one for each ADC pair. The output
of each buffer needs to be decoupled with a 10µF
capacitor between pin pairs 53 and 54, 55 and 56,
and 57 and 58. The 10µF capacitors are available as
ceramic 0805-SMD components and in X5R quality.
The internal reference buffers can be powered down
to decrease the power dissipation of the device. In
this case, external reference drivers can be
connected to REFC_A, REFC_B, and REFC_C pins.
With 10µF decoupling capacitors, the minimum
required bandwidth can be calculated using
Equation 4:
ln(2)
f-3dB =
2p ´ tCONV
(4)
With the minimum tCONV of 1.09µs, the external
reference buffers require a minimum bandwidth of
1.02kHz.
Table 1. DAC Setting Examples (2.5V Operation)
DECIMAL
CODE
BINARY
CODE
0.500
204
00 1100 1100
CC
1.25
511
01 1111 1111
1FF
2.500
1023
11 1111 1111
3FF
VREF
OUT
(V)
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CODE
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DIGITAL
This section describes the digital control and the
timing of the device in detail.
Device Configuration
Depending on the desired mode of operation, the
ADS8556/7/8 can be configured using the external
pins and/or the control register (CR), as shown in
Table 2.
Parallel Interface
To use the device with the parallel interface, the
PAR/SER pin should be held low. The maximum
achievable data throughput rate using the internal
clock is 630kSPS for the ADS8556, 670kSPS for the
ADS8557, and 730kSPS for the ADS8558 in this
case.
Access to the ADS8556/7/8 is controlled as illustrated
in Figure 2 and Figure 3.
The device can either operate with a 16-bit
(WORD/BYTE pin set low) or an 8-bit (WORD/BYTE
pin set high) parallel interface. If 8-bit operation is
used, the HBEN pin selects if the low-byte (DB7 low)
or the high-byte (DB7 high) is available on the data
output DB[15:8] first.
Serial Interface
The serial interface mode is selected by setting the
PAR/SER pin high. In this case, each data transfer
starts with the falling edge of the frame
synchronization input (FS). The conversion results
are presented on the serial data output pins SDO_A,
SDO_B, and SDO_C depending on the selections
made using the SEL_x pins. Starting with the most
significant bit (MSB), the output data are changed at
the rising edge of SCLK, so that the host processor
can read it at the following falling edge. Output data
of the ADS8557 and ADS8558 maintain the 16-bit
format with leading zeros.
Serial data input SDI are latched at the falling edge of
SCLK.
The serial interface can be used with one, two, or
three output ports. These ports are enabled with pins
SEL_A, SEL_B, and SEL_C. If all three serial data
output ports (SDO_A, SDO_B, and SDO_C) are
selected, the data can be read with either two 16-bit
data transfers or with one 32-bit data transfer. The
data of channels CH_x0 are available first, followed
by data from channels CH_x1. The maximum
achievable data throughput rate is 450kSPS for the
ADS8556, 470kSPS for the ADS8557, and 500kSPS
for the ADS8558 in this case.
If the application allows a data transfer using two
ports only, SDO_A and SDO_B outputs are used.
The device outputs data from channel CH_A0
followed by CH_A1 and CH_C0 on SDO_A, while
data from channel CH_B0 followed by CH_B1 and
CH_C1 occurs on SDO_B. In this case, a data
transfer of three consecutive 16-bit words or one
continuous 48-bit word is supported. The maximum
achievable data throughput rate is 375kSPS for the
ADS8556, 390kSPS for the ADS8557, and 400kSPS
for the ADS8558.
The output SDO_A is selected if only one serial data
port is used in the application. The data are available
in the following order: CH_A0, CH_A1, CH_B0,
CH_B1, CH_C0, and, finally CH_C1. Data can be
read using six 16-bit transfers, three 32-bit transfers,
or a single 96-bit transfer. The maximum achievable
data throughput rate is 250kSPS for the ADS8556/7
and 260kSPS for the ADS8558 in this case.
Figure 1 (the serial operation timing diagram) and
Figure 36 show all possible scenarios in more detail.
Table 2. ADS8556/7/8 Configuration Settings
INTERFACE MODE
HARDWARE MODE (HW/SW = 0)
CONVERSION START CONTROLLED BY SEPARATE
CONVST_x PINS
SOFTWARE MODE (HW/SW = 1)
CONVERSION START CONTROLLED BY CONVST_A
PIN ONLY, EXCEPT IN SEQUENTIAL MODE
Parallel
(PAR/SER = 0)
Configuration using pins, optionally, control bits C[22:18],
C[15:13], and C[9:0]
Configuration using control register bits C[31:0] only;
status of pins 27 (only if used as RANGE input) and 63 is
disregarded
Serial
(PAR/SER = 1)
Configuration using control register bits C[31:0] only;
status of pins 1, 27 (only if used as RANGE input), and
Configuration using pins, optionally, control bits C[22:18],
63 is disregarded; each access requires a control register
C[15:13], and C[9:0]; bits C[31:24] are disregarded
update via SDI (see the Serial Interface section for
details)
26
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CONVST_A
CONVST_B
CONVST_C
BUSY
(C20 = C21 = 0)
48 SCLKs
SEL_A = SEL_B = 1, SEL_C = 0
FS
SDO_A
CHA0
CHA1
CHC0
SDO_B
CHB0
CHB1
CHC1
SEL_A = 1, SEL_B = SEL_C = 0
96 SCLKs
FS
SDO_A
CHA0
CHA1
CHB0
CHB1
CHC0
CHC1
Figure 36. Serial Interface: Data Output with One or Two Active SDOs
Hardware Mode
With the HW/SW input (pin 62) set low, the device
functions are controlled via the pins and, optionally,
control register bits C[22:18], C[15:13], and C[9:0].
It is possible to generally use the part in hardware
mode but to switch it into software mode to initialize
or adjust the control register settings (for example,
the internal reference DAC) and back to hardware
mode thereafter.
Software Mode
When the HW/SW input is set high, the device
operates in software mode with functionality set only
by the control register bits (corresponding pin settings
are ignored).
If parallel interface is used, an update of all control
register settings is performed by issuing two 16-bit
write accesses on pins DB[15:0] in word mode or four
8-bit accesses on pins DB[15:8] in byte mode (to
avoid losing data, the entire sequence must be
finished before starting a new conversion). CS should
be held low during the two or four write accesses to
completely update the configuration register. It is also
possible to update only the upper eight bits (C[31:24])
using a single write access and pins DB[15:8] in both
word and byte modes. In word mode, the first write
access updates only the upper eight bits and stores
the lower eight bits (C[23:16]) for an update that
takes place with the second write access along with
C[15:0].
If the serial interface is used, input data containing
control register contents are required with each read
access to the device in this mode (combined
read/write access). For initialization purposes, all 32
bits of the register should be set (bit C16 must be set
to '1' during that access to allow the update of the
entire register content). To minimize switching noise
on the interface, an update of the first eight bits
(C[31:24]) with the remaining bits held low can be
performed thereafter.
Figure 37 illustrates the different control register
update options.
Control Register (CR);
Default Value = 0x000003FF
The control register settings can only be changed in
software mode and are not affected when switching
to hardware mode thereafter. The register values are
independent from input pin settings. Changes are
active with the rising edge of WR in parallel interface
mode or with the 32nd falling SCLK edge of the
access in which the register content has been
updated in serial mode. Optionally, the register can
also be partially updated by writing only the upper
eight bits (C[31:24]). The CR content is defined in
Table 3.
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RESET
(or Power-Up)
BUSY
(C20 = C21 = 0)
PAR/SER = 1
FS
C[31:0]
Initialization Data
SDI
Continuous Update
Continuous Update
C
[31:24]
C
[31:24]
PAR/SER = 0; WORD/BYTE = 0
CS
WR
Update
Initialization Data
DB[15:0]
C
[31:16]
C
[31:24]
C
[15:0]
C
[15:0]
PAR/SER = 0; WORD/BYTE = 1
WR
Update
Initialization Data
DB[15:8]
C
[31:24]
C
[23:16]
C
[15:8]
C
[31:24]
C
[7:0]
C
[23:16]
Figure 37. Control Register Update Options
28
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Table 3. Control Register (CR)
DESCRIPTION
ACTIVE IN
HARDWARE MODE
BIT
NAME
C31
CH_C
0 = Channel pair C disabled for next conversion (default)
1 = Channel pair C enabled
No
C30
CH_B
0 = Channel pair B disabled for next conversion (default)
1 = Channel pair B enabled
No
C29
CH_A
0 = Channel pair A disabled for next conversion (default)
1 = Channel pair A enabled
No
C28
RANGE_C
0 = Input voltage range selection for channel pair C: 4VREF (default)
1 = Input voltage range selection for channel pair C: 2VREF
No
C27
RANGE_B
0 = Input voltage range selection for channel pair B: 4VREF (default)
1 = Input voltage range selection for channel pair B: 2VREF
No
C26
RANGE_A
0 = Input voltage range selection for channel pair A: 4VREF (default)
1 = Input voltage range selection for channel pair A: 2VREF
No
C25
REFEN
0 = Internal reference source disabled (default)
1 = Internal reference source enabled
No
C24
REFBUF
0 = Internal reference buffers enabled (default)
1 = Internal reference buffers disabled
No
C23
SEQ
0 = Sequential convert start mode disabled (default)
1 = Sequential convert start mode enabled (bit 11 must be '1' in this case)
No
C22
A-NAP
0 = Normal operation (default)
1 = Auto-NAP feature enabled
Yes
C21
BUSY/INT
0 = BUSY/INT pin in normal mode (BUSY) (default)
1 = BUSY/INT pin in interrupt mode (INT)
Yes
C20
BUSY L/H
0 = BUSY active high while INT active low (default)
1 = BUSY active low while INT active high
Yes
C19
Don’t use
This bit is always set to '0'
—
0 = Internal reference voltage: 2.5V (default)
1 = Internal reference voltage: 3V
Yes
C18
VREF
C17
READ_EN
0 = Normal operation (conversion results available on SDO_x) (default)
1 = Control register contents output on SDO_x with next access
Yes
C16
C23:0_EN
0 = Control register bits C[31:24] update only (serial mode only) (default)
1 = Entire control register update enabled (serial mode only)
Yes
C15
PD_C
0 = Normal operation (default)
1 = Power-down for channel pair C enabled (bit 31 must be '0' in this case)
Yes
C14
PD_B
0 = Normal operation (default)
1 = Power-down for channel pair B enabled (bit 30 must be '0' in this case)
Yes
C13
PD_A
0 = Normal operation (default)
1 = Power-down for channel pair A enabled (bit 29 must be '0' in this case)
Yes
C12
Don't use
This bit is always '0'
—
C11
CLKSEL
0 = Normal operation with internal conversion clock (mandatory in hardware mode) (default)
1 = External conversion clock (applied through pin 27) used
No
C10
CLKOUT_EN
0 = Normal operation (default)
1 = Internal conversion clock available at pin 27
No
C9
REFDAC[9]
Bit 9 (MSB) of reference DAC value; default = 1
Yes
C8
REFDAC[8]
Bit 8 of reference DAC value; default = 1
Yes
C7
REFDAC[7]
Bit 7 of reference DAC value; default = 1
Yes
C6
REFDAC[6]
Bit 6 of reference DAC value; default = 1
Yes
C5
REFDAC[5]
Bit 5 of reference DAC value; default = 1
Yes
C4
REFDAC[4]
Bit 4 of reference DAC value; default = 1
Yes
C3
REFDAC[3]
Bit 3 of reference DAC value; default = 1
Yes
C2
REFDAC[2]
Bit 2 of reference DAC value; default = 1
Yes
C1
REFDAC[1]
Bit 1 of reference DAC value; default = 1
Yes
C0
REFDAC[0]
Bit 0 (LSB) of reference DAC value; default = 1
Yes
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Daisy-Chain Mode (in Serial Mode Only)
XCLK
Sequential Mode (in Software Mode with External
Conversion clock Only)
The three channel pairs of the ADS8556/7/8 can be
run in sequential mode, with the corresponding
CONVST_x signals interleaved, when an external
clock is used. To activate the device in sequential
mode, CR bits C11 (CLKSEL) and C23 (SEQ) must
be asserted. In this case, the BUSY output indicates
a finished conversion by going low (when C20 = 0) or
high (when C20 = 1) for only a single conversion
clock cycle in case of ongoing conversions of any
other channel pairs. Figure 38 shows the behavior of
the BUSY output in this mode. Each conversion start
should be initiated during the high phase of the
external clock, as shown in Figure 38. The minimum
time required between two CONVST_x pulses in the
time required to read the conversion result of a
channel (pair).
EOC
CHBx
(1)
EOC
CHAx
(1)
CONVST_A
(1)
CONVST_B
EOC
CHCx
The serial interface of the ADS8556/7/8 supports a
daisy-chain feature that allows cascading of multiple
devices to minimize the board space requirements
and simplify routing of the data and control lines. In
this case, pins DB5/DCIN_A, DB4/DCIN_B, and
DB3/DCIN_C are used as serial data inputs for
channels A, B, and C, respectively. Figure 39 shows
an example of a daisy-chain connection of three
devices sharing a common CONVST line to allow
simultaneous sampling of 18 analog channels along
with the corresponding timing diagram. To activate
the daisy-chain mode, the DCEN pin must be pulled
high. As a result of the time specifications tS1, tH1, and
tD3, the maximum SCLK frequency that may be used
in daisy-chain mode is 27.78MHz (assuming 50%
duty cycle).
CONVST_C
tCCLK
BUSY
(C20 = 0)
CS
RD
CH
A0
D[15:0]
CH
A1
CH
B0
CH
B1
CH
C0
CH
C1
(1) EOC = end of conversion (internal signal).
Figure 38. Sequential Mode Timing
Output Data Format
The data output format of the ADS8556/7/8 is binary
twos complement, as shown in Table 4.
For the ADS8557, which delivers 14-bit conversion
results, the leading two bits of the 16-bit frame are '0'
in the serial interface mode. In parallel interface
mode, the output pins DB[15:14] are held low.
Respectively, as the ADS8558 outputs 12 bits of
data, the first four bits of a serial 16-bit frame are
zeros, in parallel interface mode the output pins
DB[15:12] are held low.
Table 4. Output Data Format
BINARY CODE (HEXADECIMAL CODE)
DESCRIPTION
30
INPUT VOLTAGE VALUE
ADS8556
ADS8557
ADS8558
Positive full-scale
+4VREF or +2VREF
0111 1111 1111 1111
(7FFF)
0001 1111 1111 1111
(1FFF)
0000 0111 1111 1111
(7FF)
Midscale + 0.5LSB
VREF/(2 × resolution)
0000 0000 0000 0000
(0000)
0000 0000 0000 0000
(0000)
0000 0000 0000 0000
(0000)
Midscale – 0.5LSB
–VREF/(2 × resolution)
1111 1111 1111 1111
(FFFF)
0011 1111 1111 1111
(3FFF)
0000 1111 1111 1111
(FFF)
Negative full-scale
–4VREF or –2VREF
1000 0000 0000 0000
(8000)
0010 0000 0000 0000
(2000)
0000 1000 0000 0000
(800)
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CONVST
FS
SCLK
ADS8556
#1
ADS8556
#2
CONVST_A
CONVST_A
CONVST_A
FS
SCLK
FS
SCLK
FS
SCLK
SDO_A
SDO_B
SDO_C
DCEN = 1
ADS8556
#3
DCIN_A
DCIN_B
DCIN_C
SDO_A
SDO_B
SDO_C
DCIN_A
DCIN_B
DCIN_C
SDO_A
SDO_B
SDO_C
To
Processing
Unit
CONVST
BUSY
(C20 = C21 = 0)
FS
SDO_x #3
Don’t Care
16-Bit Data CHx0
ADS8556 #3
16-Bit Data CHx1
ADS8556 #3
16-Bit Data CHx0
ADS8556 #2
16-Bit Data CHx1
ADS8556 #2
16-Bit Data CHx0
ADS8556 #1
16-Bit Data CHx1
ADS8556 #1
Figure 39. Example of Daisy-Chaining Three ADS8556s
Reset and Power-Down Modes
AVDD (V)
The device supports two reset mechanisms: a
power-on reset (POR) and a pin-controlled reset
(RESET) that can be issued using pin 28. Both the
POR and RESET act as a master reset that causes
any ongoing conversion to be interrupted, the control
register content to be set to the default value, and all
channels to be switched into sample mode.
When the device is powered up, the POR sets the
device in default mode when AVDD reaches 1.5V.
When the device is powered down, the POR circuit
requires AVDD to remain below 125mV at least
350ms to ensure proper discharging of internal
capacitors and to ensure correct behavior of the
device when powered up again. If the AVDD drops
below 400mV but remains above 125mV (see the
undefined zone in Figure 40), the internal POR
capacitor does not discharge fully and the device
requires a pin-controlled reset to perform correctly
after the recovery of AVDD.
5.500
Specified Supply
Voltage Range
5.000
4.500
4.000
3.000
2.000
POR
Trigger Level
1.500
1.000
0.400
0.125
Undefined Zone
0
0.350
t (s)
Figure 40. POR: Relevant Voltage Levels
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The entire device, except the digital interface, can be
powered down by pulling the STBY pin low (pin 24).
As the digital interface section remains active, data
can be retrieved while in stand-by mode. To power
the part on again, the STBY pin must be brought
high. The device is ready to start a new conversion
after 10ms required to activate and settle the internal
circuitry. This user-controlled approach can be used
in applications that require lower data throughput
rates and lowest power dissipation. The content of
CR is not changed during standby mode. It is not
required to perform a pin-controlled reset after
returning to normal operation.
While the standby mode impacts the entire device,
each device channel pair can also be individually
switched off by setting control register bits C[15:13]
(PD_x). When reactivated, the relevant channel pair
requires 10ms to fully settle before starting a new
conversion. The internal reference remains active,
except all channels are powered down at the same
time.
In partial power-down mode, each of the three
channel pairs of the ADS8556/7/8 can be individually
put into a power-saving condition that reduces the
current requirement to 2mA per channel pair by
bringing the corresponding CONVST_x signal low
during an ongoing conversion when BUSY is high.
The relevant channel pair is activated again by
issuing a RESET pulse (to avoid loss of data from the
active channels, this RESET pulse should be
generated after retrieving the latest conversion
results). The next rising edge of the CONVST_x
signal should be issued at least six conversion cycle
periods after the reset pulse and starts a new
conversion, as shown in Figure 41. The internal
reference remains active during the partial
power-down mode.
The auto-NAP power-down mode is enabled by
asserting the A-NAP bit (C22) in the control register.
If the auto-NAP mode is enabled, the ADS8556/7/8
automatically reduce the current requirement to 6mA
after finishing a conversion; thus, the end of
conversion actually activates the power-down mode.
Triggering a new conversion by applying a positive
CONVST_x edge puts the device back into normal
operation, starts the acquisition of the analog input,
and automatically starts a new conversion six
conversion clock cycles later. Therefore, a complete
conversion cycle takes 24.5 conversion clock cycles;
thus, the maximum throughput rate in auto-NAP
power-down mode is reduced to a maximum of
380kSPS for the ADS8556, 395kSPS for the
ADS8557, and 420kSPS for the ADS8558 in serial
mode. In parallel mode, the maximum data rates are
500kSPS for the ADS8556, 530kSPS for the
ADS8557, and 580kSPS for the ADS8558. The
internal reference remains active during the auto-NAP
mode. Table 5 compares the analog current
requirements of the devices in the different modes.
BUSY
CONVST_A/C
ADC CH_Ax/Cx ACQ
CONV
ACQ
CONV
ACQ
CONV
ACQ
CONVST_B
6 ´ tCCLK Min
RESET
ADC CH_Bx
ACQ CONV
Power-Down
ACQ
Figure 41. Partial Power-Down
32
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Table 5. Maximum Analog Current (IAVDD) Demand of the ADS8556/7/8
ENABLED BY
ACTIVATED
BY
NORMAL
OPERATION
TO
POWERDOWN DELAY
Normal operation
12mA/channel
pair (maximum
data rate)
Power on
CONVST_x
—
—
—
—
Power off
Partial
power-down of
channel pair x
2mA (channel
pair x)
Power on
CONVST_x
low while
BUSY is high
At falling edge
of BUSY
RESET pulse
Immediate
6 × tCCLK
Power off
Auto-NAP
6mA
A-NAP = 1 (CR
bit)
Each end of
conversion
At falling edge
of BUSY
CONVST_x
Immediate
6 × tCCLK
A-NAP = 0 (CR
bit)
Power-down of
channel pair x
16µA (channel
pair x)
HW/SW = 1
PD_x = 1 (CR
bit)
Immediate
PD_x = 0 (CR
bit)
Immediate after
completing
register update
10ms
HW/SW = 0
Stand-by
50µA
Power on
STBY = 0
Immediate
STBY = 1
Immediate
10ms
Power off
OPERATIONAL
MODE
ANALOG
CURRENT
(IAVDD)
GROUNDING
All GND pins should be connected to a clean ground
reference. This connection should be kept as short as
possible to minimize the inductance of this path. It is
recommended to use vias connecting the pads
directly to the ground plane. In designs without
ground planes, the ground trace should be kept as
wide as possible. Avoid connections that are too
close to the grounding point of a microcontroller or
digital signal processor.
Depending on the circuit density on the board,
placement of the analog and digital components, and
the related current loops, a single solid ground plane
for the entire printed circuit board (PCB) or a
dedicated analog ground area may be used. In case
of a separated analog ground area, ensure a
low-impedance connection between the analog and
digital ground of the ADC by placing a bridge
underneath (or next) to the ADC. Otherwise, even
short undershoots on the digital interface lower than
–300mV lead to the conduction of ESD diodes
causing current flow through the substrate and
degrading the analog performance.
During PCB layout, care should be taken to avoid any
return currents crossing sensitive analog areas or
signals.
SUPPLY
The ADS8556/7/8 require four separate supplies: the
analog supply for the ADC (AVDD), the buffer I/O
supply for the digital interface (BVDD), and the
high-voltage supplies driving the analog input circuitry
(HVDD and HVSS). Generally, there are no specific
requirements with regard to the power sequencing of
the device. However, when HVDD is supplied before
AVDD, the internal ESD structure conducts,
increasing IHVDD beyond the specified value.
RESUMED BY
POWER-UP
TO NORMAL
OPERATION
DELAY
POWER-UP
TO NEXT
CONVERSION
START TIME
DISABLED BY
The AVDD supply provides power to the internal
circuitry of the ADC. It can be set in the range of 4.5V
to 5.5V. Because the supply current of the device is
typically 30mA, it is not possible to use a passive
filter between the digital board supply of the
application and the AVDD pin. A linear regulator is
recommended to generate the analog supply voltage.
Each AVDD pin should be decoupled to AGND with a
100nF capacitor. In addition, a single 10µF capacitor
should be placed close to the device but without
compromising the placement of the smaller capacitor.
Optionally, each supply pin can be decoupled using a
1µF ceramic capacitor without the requirement for a
10µF capacitor.
The BVDD supply is only used to drive the digital I/O
buffers and can be set in the range of 2.7V to 5.5V.
This range allows the device to interface with most
state-of-the-art processors and controllers. To limit
the noise energy from the external digital circuitry to
the device, BVDD should be filtered. A 10Ω resistor
can be placed between the external digital circuitry
and the device, because the current drawn is typically
below 2mA (depending on the external loads). A
bypass ceramic capacitor of 1µF (or alternatively, a
pair of 100nF and 10µF capacitors) should be placed
between the BVDD pin and pin 8.
The high-voltage supplies (HVSS and HVDD) are
connected to the analog inputs. Noise and glitches on
these supplies directly couple into the input signals.
Place a 100nF ceramic decoupling capacitor, located
as close to the device as possible, between each of
pins 30, 31, and AGND. An additional 10µF capacitor
is used that should be placed close to the device but
without compromising the placement of the smaller
capacitor.
Figure 42 shows a layout recommendation for the
ADS8556/7/8 along with the proper decoupling and
reference capacitor placement and connections.
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ADS8556/7/8
Top View
To AVDD
To AVDD
To DUT
AVDD Source
10
mF
AVDD
51
0.1mF
AGND
54
0.47mF
AGND
56
10mF
AGND
58
10mF
AGND
61
AGND
62
10mF
1
48
2
AVDD
3
AVDD
4
45
5
AGND
6
AGND
7
42
BGND
AVDD
BVDD
AVDD
10
39
14
AVDD
15
AVDD
16
33
17
18
19
20
21 22
23
24
0.1mF
To
AVDD
LEGEND
27
28
29
0.1
mF
To AVDD
0.1
mF
0.1
mF
To AVDD
0.1
mF
0.1
mF
To AVDD
0.1
mF
AGND
36
HVDD
AGND
13
HVSS
AGND
AVDD
11
12
AGND
1
mF
To
BVDD
63
AVDD
64
AGND
0.1mF
0.1mF
0.1mF
10mF
10mF
To
HVSS/HVDD
TOP layer; copper pour and traces
Lower layer; AGND area
Lower layer; BGND area
Via
(1) All 0.1µF, 0.47µF, and 1µF capacitors should be placed as close to the ADS8556/7/8 as possible.
(2) All 10µF capacitors should be close to the device but without compromising the placement of the smaller capacitors.
Figure 42. Layout Recommendation
34
Copyright © 2006–2009, Texas Instruments Incorporated
Product Folder Link(s): ADS8556 ADS8557 ADS8558
ADS8556
ADS8557
ADS8558
www.ti.com ............................................................................................................................................... SBAS404A – OCTOBER 2006 – REVISED AUGUST 2009
APPLICATION INFORMATION
The actual values of the resistors and capacitors
depend on the bandwidth and performance
requirements of the application. For highest data rate,
it is recommended to use a filter capacitor value of
1nF and a series resistor of 22Ω to fulfill the settling
requirements to an accuracy level of 16 bits within the
acquisition time of 280ns.
The minimum configuration of the ADS8556/7/8 in
parallel mode is shown in Figure 43. In this case, the
BUSY signal is not used while the SW generates the
required signals in a timely manner. TI’s OPA2211 is
used as an input driver, supporting bandwidth that
allows running the device at the maximum data rate.
R1
AGND
R2
AVDD
ADS8556
RF
CH_A0
Input #1
CF
OPA2211
CF
RF
Input #2
BVDD
AGND
STBY
CH_A1
RANGE
REFEN/WR
R1
R2
AGND
REFC_A
10mF
AGND
R1
AGND
CONVST_A
10mF
R2
REFC_B
AGND
CONVST_B
CONVST_C
AVDD
RESET
RD
CH_B0
Input #3
CF
OPA2211
DB[15:0]
AGND
CF
RF
Input #4
Host
Controller
CS
RF
CH_B1
R1
R2
AGND
REFIO
0.47mF
AGND
R1
AGND
R2
10mF
REFC_C
AGND
AVDD
ADS8556
AVDD
RF
CH_C0
Input #5
CF
OPA2211
HW/SW
AVDD
PAR/SER
AVDD
WORD/BYTE
AGND
RF
Input #6
AVDD
AVDD
BVDD
BVDD
AGND
BGND
CF
AGND
CH_C1
1m F
BGND
AGND
BGND
AGND
AGND
R1
R2
AGND
AGND
HVSS
AGND
AGND
0.1mF
AGND
10mF
0.1mF
0.1mF
0.1mF
0.1mF
0.1mF
0.1mF
0.1mF
AGND
HVSS
AGND
AGND
AGND
AGND
AVDD
AVDD
0.1mF
10mF
0.1mF
10mF
AGND
HVDD
AVDD
AVDD
AVDD
HVSS
AVDD
Figure 43. Minimum Configuration in Parallel Interface Mode
Copyright © 2006–2009, Texas Instruments Incorporated
Product Folder Link(s): ADS8556 ADS8557 ADS8558
35
PACKAGE OPTION ADDENDUM
www.ti.com
31-Aug-2009
PACKAGING INFORMATION
Orderable Device
Status (1)
Package
Type
Package
Drawing
Pins Package Eco Plan (2)
Qty
ADS8556IPM
ACTIVE
LQFP
PM
64
160
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
ADS8556IPMR
ACTIVE
LQFP
PM
64
1000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
ADS8557IPM
ACTIVE
LQFP
PM
64
160
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
ADS8557IPMR
ACTIVE
LQFP
PM
64
1000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
ADS8558IPM
ACTIVE
LQFP
PM
64
160
Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
ADS8558IPMR
ACTIVE
LQFP
PM
64
1000 Green (RoHS &
no Sb/Br)
CU NIPDAU
Level-3-260C-168 HR
Lead/Ball Finish
MSL Peak Temp (3)
(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)
Eco Plan - The planned eco-friendly classification: Pb-Free (RoHS), Pb-Free (RoHS Exempt), or Green (RoHS & no Sb/Br) - please check
http://www.ti.com/productcontent for the latest availability information and additional product content details.
TBD: The Pb-Free/Green conversion plan has not been defined.
Pb-Free (RoHS): TI's terms "Lead-Free" or "Pb-Free" mean semiconductor products that are compatible with the current RoHS requirements
for all 6 substances, including the requirement that lead not exceed 0.1% by weight in homogeneous materials. Where designed to be soldered
at high temperatures, TI Pb-Free products are suitable for use in specified lead-free processes.
Pb-Free (RoHS Exempt): This component has a RoHS exemption for either 1) lead-based flip-chip solder bumps used between the die and
package, or 2) lead-based die adhesive used between the die and leadframe. The component is otherwise considered Pb-Free (RoHS
compatible) as defined above.
Green (RoHS & no Sb/Br): TI defines "Green" to mean Pb-Free (RoHS compatible), and free of Bromine (Br) and Antimony (Sb) based flame
retardants (Br or Sb do not exceed 0.1% by weight in homogeneous material)
(3)
MSL, Peak Temp. -- The Moisture Sensitivity Level rating according to the JEDEC industry standard classifications, and peak solder
temperature.
Important Information and Disclaimer:The information provided on this page represents TI's knowledge and belief as of the date that it is
provided. TI bases its knowledge and belief on information provided by third parties, and makes no representation or warranty as to the
accuracy of such information. Efforts are underway to better integrate information from third parties. TI has taken and continues to take
reasonable steps to provide representative and accurate information but may not have conducted destructive testing or chemical analysis on
incoming materials and chemicals. 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 MATERIALS INFORMATION
www.ti.com
22-Sep-2009
TAPE AND REEL INFORMATION
*All dimensions are nominal
Device
Package Package Pins
Type Drawing
SPQ
Reel
Reel
A0
Diameter Width (mm)
(mm) W1 (mm)
B0
(mm)
K0
(mm)
P1
(mm)
W
Pin1
(mm) Quadrant
ADS8556IPMR
LQFP
PM
64
1000
330.0
24.4
12.3
12.3
2.5
16.0
24.0
Q2
ADS8557IPMR
LQFP
PM
64
1000
330.0
24.4
12.3
12.3
2.5
16.0
24.0
Q2
ADS8558IPMR
LQFP
PM
64
1000
330.0
24.4
12.3
12.3
2.5
16.0
24.0
Q2
Pack Materials-Page 1
PACKAGE MATERIALS INFORMATION
www.ti.com
22-Sep-2009
*All dimensions are nominal
Device
Package Type
Package Drawing
Pins
SPQ
Length (mm)
Width (mm)
Height (mm)
ADS8556IPMR
LQFP
PM
64
1000
346.0
346.0
41.0
ADS8557IPMR
LQFP
PM
64
1000
346.0
346.0
41.0
ADS8558IPMR
LQFP
PM
64
1000
346.0
346.0
41.0
Pack Materials-Page 2
MECHANICAL DATA
MTQF008A – JANUARY 1995 – REVISED DECEMBER 1996
PM (S-PQFP-G64)
PLASTIC QUAD FLATPACK
0,27
0,17
0,50
0,08 M
33
48
49
32
64
17
0,13 NOM
1
16
7,50 TYP
Gage Plane
10,20
SQ
9,80
12,20
SQ
11,80
0,25
0,05 MIN
0°– 7°
0,75
0,45
1,45
1,35
Seating Plane
0,08
1,60 MAX
4040152 / C 11/96
NOTES: A.
B.
C.
D.
All linear dimensions are in millimeters.
This drawing is subject to change without notice.
Falls within JEDEC MS-026
May also be thermally enhanced plastic with leads connected to the die pads.
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