SBAS456B December   2008  – January 2016 ADS7828-Q1

PRODUCTION DATA.  

  1. 1 Features
  2. 2 Applications
  3. 3 Description
  4. 4 Revision History
  5. 5 Pin Configuration and Functions
  6. 6 Specifications
    1. 6.1  Absolute Maximum Ratings
    2. 6.2  ESD Ratings
    3. 6.3  Recommended Operating Conditions
    4. 6.4  Thermal Information
    5. 6.5  Electrical Characteristics for ADS7828E
    6. 6.6  Electrical Characteristics for ADS7828EB
    7. 6.7  Electrical Characteristics for ADS7828E
    8. 6.8  Electrical Characteristics for ADS7828EB
    9. 6.9  Switching Characteristics
    10. 6.10 Typical Characteristics
  7. 7 Detailed Description
    1. 7.1 Overview
    2. 7.2 Functional Block Diagram
    3. 7.3 Feature Description
      1. 7.3.1 Analog Input
      2. 7.3.2 Reference
      3. 7.3.3 Digital Interface
    4. 7.4 Device Functional Modes
      1. 7.4.1 Address Byte
      2. 7.4.2 Command Byte
      3. 7.4.3 Initiating Conversion
      4. 7.4.4 Reading Data
      5. 7.4.5 Reading in Fast or Standard (F/S) Mode
      6. 7.4.6 Reading in High-Speed (HS) Mode
      7. 7.4.7 Reading With Reference On or Off
  8. 8 Application and Implementation
    1. 8.1 Application Information
      1. 8.1.1 Basic Connections
        1. 8.1.1.1 Connecting Multiple Devices
        2. 8.1.1.2 Using GPIO Ports for Communication
        3. 8.1.1.3 Single-Ended Inputs
    2. 8.2 Typical Applications
      1. 8.2.1 ADS7828-Q1 With Current Shunt Monitor
        1. 8.2.1.1 Design Requirements
        2. 8.2.1.2 Detailed Design Procedure
          1. 8.2.1.2.1 Part Selection
          2. 8.2.1.2.2 Full-Scale Differential Range
          3. 8.2.1.2.3 Circuit Implementation
        3. 8.2.1.3 Application Curve
  9. 9 Power Supply Recommendations
  10. 10Layout
    1. 10.1 Layout Guidelines
    2. 10.2 Layout Example
  11. 11Device and Documentation Support
    1. 11.1 Documentation Support
      1. 11.1.1 Related Documentation
    2. 11.2 Community Resources
    3. 11.3 Trademarks
    4. 11.4 Electrostatic Discharge Caution
    5. 11.5 Glossary
  12. 12Mechanical, Packaging, and Orderable Information

Package Options

Mechanical Data (Package|Pins)
Thermal pad, mechanical data (Package|Pins)
Orderable Information

6 Specifications

6.1 Absolute Maximum Ratings

over operating free-air temperature range, unless otherwise noted.(1)(2)
MIN MAX UNIT
VDD Supply voltage –0.3 6 V
VIN Digital input voltage –0.3 0.3 V
θJA Thermal impedance, junction to free air(3)(4) 108.4 °C/W
TA Operating free-air temperature –40 85 °C
Tlead Lead temperature during soldering Vapor phase (60 seconds) 215 °C
Infrared (15 seconds) 220 °C
TJ Operating virtual-junction temperature 150 °C
Tstg Storage temperature –65 150 °C
(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) All voltages are with respect to the GND terminal.
(3) The package thermal impedance is calculated in accordance with JESD 51-7.
(4) Maximum power dissipation is a function of TJ(max), θJA, and TA. The maximum allowable power dissipation at any allowable ambient temperature is PD = (TJ(max) – TA)/θJA. Operating at the absolute maximum TJ of 150°C can impact reliability.

6.2 ESD Ratings

VALUE UNIT
V(ESD) Electrostatic discharge Human-body model (HBM), per AEC Q100-002(1) ±2000 V
Charged-device model (CDM), per AEC Q100-011 ±1000
(1) AEC Q100-002 indicates that HBM stressing shall be in accordance with the ANSI/ESDA/JEDEC JS-001 specification.

6.3 Recommended Operating Conditions

over operating free-air temperature range (unless otherwise noted)
MIN NOM MAX UNIT
VDD Supply Voltage 2.7-V nominal 2.7 3.6 V
5-V nominal 4.75 5 5.25
VIN Analog Input Voltage Positive Input –0.2 +VDD + 0.2 V
Negative Input –0.2 0.2
Full-scale differential (Positive input – Negative input) 0 VREF
VIN(REF) Voltage Reference Input voltage 0.05 +VDD V
VIH High-level digital input voltage 0.7 × +VDD +VDD + 0.5 V
VIL Low-level digital input voltage –0.3 0.3 × +VDD V
TA Operating free-air temperature –40 85 °C

6.4 Thermal Information

over operating free-air temperature range (unless otherwise noted)
THERMAL METRIC(1) ADS7828-Q1 UNIT
PW (TSSOP)
16 PINS
RθJA Junction-to-ambient thermal resistance 102.1 °C/W
RθJC(top) Junction-to-case (top) thermal resistance 37.2 °C/W
RθJB Junction-to-board thermal resistance 47.1 °C/W
ψJT Junction-to-top characterization parameter 2.9 °C/W
ψJB Junction-to-board characterization parameter 46.5 °C/W
(1) For more information about traditional and new thermal metrics, see the Semiconductor and IC Package Thermal Metrics application report, SPRA953.

6.5 Electrical Characteristics for ADS7828E

+VDD = 2.7 V, VREF = 2.5 V, SCL clock frequency = 3.4 MHz (high-speed mode), over operating free-air temperature range, unless otherwise noted.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Analog Input
Ileak Leakage current ±1 µA
CI 25 pF
Overall Performance
No missing codes 12 bits
Integral linearity error ±1 ±2 LSB(1)
Differential linearity error ±1 LSB
Offset error ±1 ±3 LSB
Offset error match ±0.2 ±1 LSB
Gain error ±1 ±4 LSB
Gain error match ±0.2 ±1 LSB
Vn Noise RMS 33 µV
PSRR Power-supply ripple rejection 82 dB
Sampling Dynamics
Throughput frequency High-speed mode: SCL = 3.4 MHz 50 kHz
Fast mode: SCL = 400 kHz 8
Standard mode: SCL = 100 kHz 2
Conversion time 6 µs
AC Accuracy
THD Total harmonic distortion(2) VIN = 25 VPP at 10 kHz –82 dB
Signal-to-noise ratio VIN = 25 VPP at 10 kHz 72 dB
Signal-to-(noise + distortion) ratio VIN = 25 VPP at 10 kHz 71 dB
Spurious-free dynamic range VIN = 25 VPP at 10 kHz 86 dB
Channel-to-channel isolation 120 dB
Voltage Reference Output
VO Output voltage 2.475 2.5 2.525 V
Internal reference drift 15 ppm/°C
zo Output impedance Internal reference on 110 Ω
Internal reference off 1 GΩ
IQ Quiescent current 850 µA
Voltage Reference Input
rI Input resistance 1 GΩ
Current drain 20 µA
Digital Input and Output
VOL Low-level output voltage Minimum 3-mA sink current 0.4 V
IIH High-level input current VIH = +VDD + 0.5 V 10 µA
IIL Low-level input current VIL = –0.3 V –10 µA
Power Supply
IQ Quiescent current High-speed mode: SCL = 3.4 MHz 225 320 µA
Fast mode: SCL = 400 kHz 100
Standard mode: SCL = 100 kHz 60
PO Power dissipation High-speed mode: SCL = 3.4 MHz 675 1000 µW
Fast mode: SCL = 400 kHz 300
Standard mode: SCL = 100 kHz 180
Power-down current with wrong address selected High-speed mode: SCL = 3.4 MHz 70 µA
Fast mode: SCL = 400 kHz 25
Standard mode: SCL = 100 kHz 6
IPD Full power-down current SCL pulled high, SDA pulled high 400 3000 nA
(1) LSB means Least Significant Bit; with VREF equal to 2.5 V, one LSB is 610 µV.
(2) THD is measured to the ninth harmonic.

6.6 Electrical Characteristics for ADS7828EB

+VDD = 2.7 V, VREF = 2.5 V, SCL clock frequency = 3.4 MHz (high-speed mode), over operating free-air temperature range, unless otherwise noted.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Analog Input
Ileak Leakage current ±1 µA
CI 25 pF
Overall Performance
No missing codes 12 bits
Integral linearity error ±0.5 ±1 LSB(1)
Differential linearity error ±0.5 –1 to 2 LSB
Offset error ±0.75 ±2 LSB
Offset error match ±0.2 ±1 LSB
Gain error ±0.75 ±3 LSB
Gain error match ±0.2 ±1 LSB
Vn Noise RMS 33 µV
PSRR Power-supply ripple rejection 82 dB
Sampling Dynamics
Throughput frequency High-speed mode: SCL = 3.4 MHz 50 kHz
Fast mode: SCL = 400 kHz 8
Standard mode: SCL = 100 kHz 2
Conversion time 6 µs
AC Accuracy
THD Total harmonic distortion(2) VIN = 25 VPP at 10 kHz –82 dB
Signal-to-noise ratio VIN = 25 VPP at 10 kHz 72 dB
Signal-to-(noise + distortion) ratio VIN = 25 VPP at 10 kHz 71 dB
Spurious-free dynamic range VIN = 25 VPP at 10 kHz 86 dB
Channel-to-channel isolation 120 dB
Voltage Reference Output
VO Output voltage 2.475 2.5 2.525 V
Internal reference drift 15 ppm/°C
zo Output impedance Internal reference on 110 Ω
Internal reference off 1 GΩ
IQ Quiescent current 850 µA
Voltage Reference Input
rI Input resistance 1 GΩ
Current drain 20 µA
Digital Input and Output
VOL Low-level output voltage Minimum 3-mA sink current 0.4 V
IIH High-level input current VIH = +VDD + 0.5 V 10 µA
IIL Low-level input current VIL = –0.3 V –10 µA
Power Supply
IQ Quiescent current High-speed mode: SCL = 3.4 MHz 225 320 µA
Fast mode: SCL = 400 kHz 100
Standard mode: SCL = 100 kHz 60
PO Power dissipation High-speed mode: SCL = 3.4 MHz 675 1000 µW
Fast mode: SCL = 400 kHz 300
Standard mode: SCL = 100 kHz 180
Power-down current with wrong address selected High-speed mode: SCL = 3.4 MHz 70 µA
Fast mode: SCL = 400 kHz 25
Standard mode: SCL = 100 kHz 6
IPD Full power-down current SCL pulled high, SDA pulled high 400 3000 nA
(1) LSB means Least Significant Bit; with VREF equal to 2.5 V, one LSB is 610 µV.
(2) THD is measured to the ninth harmonic.

6.7 Electrical Characteristics for ADS7828E

+VDD = 5 V, VREF = External 5 V, SCL clock frequency = 3.4 MHz (high-speed mode), over operating free-air temperature range, unless otherwise noted.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Analog Input
Ileak Leakage current ±1 µA
CI 25 pF
Overall Performance
No missing codes 12 bits
Integral linearity error ±1 ±2 LSB(1)
Differential linearity error ±1 LSB
Offset error ±1 ±3 LSB
Offset error match ±1.5 LSB
Gain error ±1 ±3 LSB
Gain error match ±1 LSB
Vn Noise RMS 33 µV
PSRR Power-supply ripple rejection 82 dB
Sampling Dynamics
Throughput frequency High-speed mode: SCL = 3.4 MHz 50 kHz
Fast mode: SCL = 400 kHz 8
Standard mode: SCL = 100 kHz 2
Conversion time 6 µs
AC Accuracy
THD Total harmonic distortion(2) VIN = 25 VPP at 10 kHz –82 dB
Signal-to-noise ratio VIN = 25 VPP at 10 kHz 72 dB
Signal-to-(noise + distortion) ratio VIN = 25 VPP at 10 kHz 71 dB
Spurious-free dynamic range VIN = 25 VPP at 10 kHz 86 dB
Channel-to-channel isolation 120 dB
Voltage Reference Output
VO Output voltage 2.475 2.5 2.525 V
Internal reference drift 15 ppm/°C
zo Output impedance Internal reference on 110 Ω
Internal reference off 1 GΩ
IQ Quiescent current 1300 µA
Voltage Reference Input
rI Input resistance 1 GΩ
Current drain 20 µA
Digital Input and Output
VOL Low-level output voltage Minimum 3-mA sink current 0.4 V
IIH High-level input current VIH = +VDD + 0.5 V 10 µA
IIL Low-level input current VIL = –0.3 V –10 µA
Power Supply
IQ Quiescent current High-speed mode: SCL = 3.4 MHz 750 100 µA
Fast mode: SCL = 400 kHz 300
Standard mode: SCL = 100 kHz 150
PO Power dissipation High-speed mode: SCL = 3.4 MHz 3.75 5 µW
Fast mode: SCL = 400 kHz 1.5
Standard mode: SCL = 100 kHz 0.75
Power-down current with wrong address selected High-speed mode: SCL = 3.4 MHz 400 µA
Fast mode: SCL = 400 kHz 150
Standard mode: SCL = 100 kHz 35
IPD Full power-down current SCL pulled high, SDA pulled high 400 3000 nA
(1) LSB means Least Significant Bit; with VREF equal to 5 V, one LSB is 1.22 mV.
(2) THD is measured to the ninth harmonic.

6.8 Electrical Characteristics for ADS7828EB

+VDD = 5 V, VREF = External 5 V, SCL clock frequency = 3.4 MHz (high-speed mode), over operating free-air temperature range, unless otherwise noted.
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
Analog Input
Ileak Leakage current ±1 µA
CI 25 pF
Overall Performance
No missing codes 12 bits
Integral linearity error ±0.5 ±1 LSB(1)
Differential linearity error ±0.5 –1 to 2 LSB
Offset error ±0.75 ±2 LSB
Offset error match ±1 LSB
Gain error ±0.75 ±2 LSB
Gain error match ±1 LSB
Vn Noise RMS 33 µV
PSRR Power-supply ripple rejection 82 dB
Sampling Dynamics
Throughput frequency High-speed mode: SCL = 3.4 MHz 50 kHz
Fast mode: SCL = 400 kHz 8
Standard mode: SCL = 100 kHz 2
Conversion time 6 µs
AC Accuracy
THD Total harmonic distortion(2) VIN = 25 VPP at 10 kHz –82 dB
Signal-to-noise ratio VIN = 25 VPP at 10 kHz 72 dB
Signal-to-(noise + distortion) ratio VIN = 25 VPP at 10 kHz 71 dB
Spurious-free dynamic range VIN = 25 VPP at 10 kHz 86 dB
Channel-to-channel isolation 120 dB
Voltage Reference Output
VO Output voltage 2.475 2.5 2.525 V
Internal reference drift 15 ppm/°C
zo Output impedance Internal reference on 110 Ω
Internal reference off 1 GΩ
IQ Quiescent current 1300 µA
Voltage Reference Input
rI Input resistance 1 GΩ
Current drain 20 µA
Digital Input and Output
VOL Low-level output voltage Minimum 3-mA sink current 0.4 V
IIH High-level input current VIH = +VDD + 0.5 V 10 µA
IIL Low-level input current VIL = –0.3 V –10 µA
Power Supply
IQ Quiescent current High-speed mode: SCL = 3.4 MHz 750 1000 µA
Fast mode: SCL = 400 kHz 300
Standard mode: SCL = 100 kHz 150
PO Power dissipation High-speed mode: SCL = 3.4 MHz 3.75 5 µW
Fast mode: SCL = 400 kHz 1.5
Standard mode: SCL = 100 kHz 0.75
Power-down current with wrong address selected High-speed mode: SCL = 3.4 MHz 400 µA
Fast mode: SCL = 400 kHz 150
Standard mode: SCL = 100 kHz 35
IPD Full power-down current SCL pulled high, SDA pulled high 400 3000 nA
(1) LSB means Least Significant Bit; with VREF equal to 5 V, one LSB is 1.22 mV.
(2) THD is measured to the ninth harmonic.

6.9 Switching Characteristics

+VDD = 2.7 V, over operating free-air temperature range, unless otherwise noted.(1)(2) See Figure 1.
PARAMETER TEST CONDITIONS MIN MAX UNIT
fSCL SCL clock frequency Standard mode 100 kHz
Fast mode 400
High-speed mode Cb = 100 pF max 3.4 MHz
Cb = 400 pF max 1.7
tBUF Bus free time between Stop and Start conditions Standard mode 4.7 μs
Fast mode 1.3
tHD; STA Hold time (repeated) Start condition Standard mode 4 μs
Fast mode 600 ns
High-speed mode 160
tlow Low period of the SCL clock Standard mode 4.7 μs
Fast mode 1.3
High-speed mode(3) Cb = 100 pF max 160 ns
Cb = 400 pF max 320
thigh High period of the SCL clock Standard mode 4 μs
Fast mode 600 ns
High-speed mode(3) Cb = 100 pF max 60
Cb = 400 pF max 120
tSU; STA Setup time for a repeated Start condition Standard mode 4.7 μs
Fast mode 600 ns
High-speed mode 160
tSU; DAT Data setup time Standard mode 250 ns
Fast mode 100
High-speed mode 10
tHD; DAT Data hold time Standard mode 0 3.45 μs
Fast mode 0 0.9
High-speed mode(3) (4) Cb = 100 pF max 0 82 ns
Cb = 400 pF max 0 162
trCL Rise time of SCL signal Standard mode 1000 ns
Fast mode 20 + 0.1Cb 300
High-speed mode(3) Cb = 100 pF max 10 40
Cb = 400 pF max 20 80
trCL1 Rise time of SCL signal after a repeated Start condition and after an acknowledge bit Standard mode 1000 ns
Fast mode 20 + 0.1Cb 300
High-speed mode(3) Cb = 100 pF max 10 80
Cb = 400 pF max 20 160
tfCL Fall time of SCL signal Standard mode 300 ns
Fast mode 20 + 0.1Cb 300
High-speed mode(3) Cb = 100 pF max 10 40
Cb = 400 pF max 20 80
trDA Rise time of SDA signal Standard mode 1000 ns
Fast mode 20 + 0.1Cb 300
High-speed mode(3) Cb = 100 pF max 10 80
Cb = 400 pF max 20 160
tfDA Fall time of SDA signal Standard mode 300 ns
Fast mode 20 + 0.1Cb 300
High-speed mode(3) Cb = 100 pF max 10 80
Cb = 400 pF max 20 160
tSU; STO Setup time for Stop condition Standard mode 4 μs
Fast mode 600 ns
High-speed mode 160
Cb Capacitive load for SDA or SCL 400 pF
tSP Pulse width of spike suppressed Fast mode 50 ns
High-speed mode 10
VnH Noise margin at the high level for each connected device (including hysteresis) 0.2 × VDD V
VnL Noise margin at the low level for each connected device (including hysteresis) 0.1 × VDD V
(1) All values referred to VIH(MIN) and VIL(MAX) levels.
(2) Not production tested, except for the perameter tHD; DAT, data hold time, high-speed mode, Cb = 100 pF max.
(3) For bus line loads (CB) between 100 pF and 400 pF, the timing parameters must be linearly interpolated.
(4) A device must internally provide a data hold time to bridge the undefined part between VIH and VIL of the falling edge of the SCLH signal. An input circuit with a threshold as low as possible for the falling edge of the SCLH signal minimizes this hold time.
ADS7828-Q1 i2c_timing_bas456.gif Figure 1. I2C Timing

6.10 Typical Characteristics

ADS7828-Q1 typ_char_1_1_bas456.gif Figure 2. Frequency Spectrum
(4096 Point FFT: fIN = 1 kHz, 0 dB)
ADS7828-Q1 typ_char_1_3_bas456.gif Figure 4. Differential Linearity Error vs Code
(2.5-V Internal Reference)
ADS7828-Q1 typ_char_1_5_bas456.gif Figure 6. Differential Linearity Error vs Code
(2.5-V External Reference)
ADS7828-Q1 typ_char_2_1_bas456.gif Figure 8. Change in Gain vs Temperature
ADS7828-Q1 typ_char_2_3_bas456.gif Figure 10. Power-Down Supply Current vs Temperature
ADS7828-Q1 typ_char_2_5_bas456.gif Figure 12. Supply Current vs I2C Bus Rate
ADS7828-Q1 typ_char_1_2_bas456.gif Figure 3. Integral Linearity Error vs Code
(2.5-V Internal Reference)
ADS7828-Q1 typ_char_1_4_bas456.gif Figure 5. Integral Linearity Error vs Code
(2.5-V External Reference)
ADS7828-Q1 typ_char_1_6_bas456.gif Figure 7. Change in Offset vs Temperature
ADS7828-Q1 typ_char_2_2_bas456.gif Figure 9. Internal Reference vs Temperature
ADS7828-Q1 typ_char_2_4_bas456.gif Figure 11. Supply Current vs Temperature
ADS7828-Q1 typ_char_2_6_bas456.gif Figure 13. Internal VREF vs Turn-On Time