Datasheet

ManualsBrandsMAXIM INTEGRATED ManualsData collecting ICsData acquisition IC - AD converter (ADC) External TQFN 12

General Description

The MAX1070/MAX1071 low-power, high-speed, serial-

output, 10-bit, analog-to-digital converters (ADCs) oper-

ate at up to 1.5Msps. These devices feature true-differen-

tial inputs, offering better noise immunity, distortion

improvements, and a wider dynamic range over single-

ended inputs. A standard SPI™/QSPI™/MICROWIRE™

interface provides the clock necessary for conversion.

These devices easily interface with standard digital signal

processor (DSP) synchronous serial interfaces.

The MAX1070/MAX1071 operate from a single +2.7V to

+3.6V supply voltage and require an external reference.

The MAX1070 has a unipolar analog input, while the

MAX1071 has a bipolar analog input. These devices fea-

ture a partial power-down mode and a full power-down

mode for use between conversions, which lower the sup-

ply current to 1mA (typ) and 1µA (max), respectively. Also

featured is a separate power-supply input (V

), which

allows direct interfacing to +1.8V to V

digital logic. The

fast conversion speed, low-power dissipation, excellent

AC performance, and DC accuracy (±0.5 LSB INL) make

the MAX1070/MAX1071 ideal for industrial process con-

trol, motor control, and base-station applications.

The MAX1070/MAX1071 come in a 12-pin TQFN pack-

age, and are available in the extended (-40°C to +85°C)

temperature range.

Applications

Data Acquisition

Bill Validation

Motor Control

Communications

Portable Instruments

Features

o 1.5Msps Sampling Rate

o Only 18mW (typ) Power Dissipation

o Only 1µA (max) Shutdown Current

o High-Speed, SPI-Compatible, 3-Wire Serial Interface

o 61dB S/(N + D) at 525kHz Input Frequency

o Internal True-Differential Track/Hold (T/H)

o External Reference

o No Pipeline Delays

o Small 12-Pin TQFN Package

MAX1070/MAX1071

1.5Msps, Single-Supply, Low-Power,

True-Differential, 10-Bit ADCs

________________________________________________________________

Maxim Integrated Products

AIN+

N.C.

SCLK

N.C.

GND

2REF

7RGND

CNVST

DOUT

MAX1070

MAX1071

AIN-

TQFN

TOP VIEW

PART

TEMP RANGE

PIN-

PACKAGE

INPUT

MAX1070ETC+T

-40°C to +85°C

12 TQFN

Unipolar

MAX1071ETC+T

-40°C to +85°C

12 TQFN Bipolar

Pin Configuration

Ordering Information

MAX1070

MAX1071

DOUT

AIN+

REF

4.7μF

10μF10μF

+2.7V TO +3.6V

0.01μF

+1.8V TO V

AIN-

REF

DIFFERENTIAL

INPUT

VOLTAGE

RGND

GND

CNVST

SCLK

μC/DSP

Typical Operating Circuit

19-3292; Rev 1; 4/09

For pricing, delivery, and ordering information, please contact Maxim Direct at 1-888-629-4642,

or visit Maxim’s website at www.maxim-ic.com.

SPI/QSPI are trademarks of Motorola, Inc.

MICROWIRE is a trademark of National Semiconductor Corp.

+Denotes a lead(Pb)-free/RoHS-compliant package.

T = Tape and reel.

Summary of content (18 pages)

PAGE 1
9-3292; Rev 1; 4/09 1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs The MAX1070/MAX1071 low-power, high-speed, serialoutput, 10-bit, analog-to-digital converters (ADCs) operate at up to 1.5Msps. These devices feature true-differential inputs, offering better noise immunity, distortion improvements, and a wider dynamic range over singleended inputs. A standard SPI™/QSPI™/MICROWIRE™ interface provides the clock necessary for conversion.
PAGE 2
MAX1070/MAX1071 1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs ABSOLUTE MAXIMUM RATINGS VDD to GND ..............................................................-0.3V to +6V VL to GND ................-0.3V to the lower of (VDD + 0.3V) and +6V Digital Inputs to GND .................-0.3V to the lower of (VDD + 0.3V) and +6V Digital Output to GND ....................-0.3V to the lower of (VL + 0.3V) and +6V Analog Inputs and REF to GND..........-0.3V to the lower of (VDD + 0.
PAGE 3
1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs (VDD = +2.7V to +3.6V, VL = VDD, VREF = 2.048V, fSCLK = 24.0MHz, 50% duty cycle, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VDD = 3V and TA = +25°C.
PAGE 4
MAX1070/MAX1071 1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs TIMING CHARACTERISTICS (VDD = +2.7V to +3.6V, VL = VDD, VREF = 2.048V, fSCLK = 24.0MHz, 50% duty cycle, TA = -40°C to +85°C, unless otherwise noted. Typical values are at VDD = 3V and TA = +25°C.) PARAMETER SYMBOL CONDITIONS MIN VL = 2.7V to VDD SCLK Pulse-Width High tCH SCLK Pulse-Width Low tCL VL = 1.8V to VDD, minimum recommended (Note 7) tDOUT MAX UNITS ns 22.5 VL = 2.
PAGE 5
1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs 19 0 2.1 2.4 2.7 3.0 3.3 3.6 MAX1070/71 toc03 -0.2 -0.2 1.8 0 -0.1 -0.1 17 0 256 512 768 -512 1024 -256 0 256 VL (V) DIGITAL OUTPUT CODE DIGITAL OUTPUT CODE DIFFERENTIAL NONLINEARITY vs. DIGITAL OUTPUT CODE (MAX1070) DIFFERENTIAL NONLINEARITY vs. DIGITAL OUTPUT CODE (MAX1071) OFFSET ERROR vs. TEMPERATURE (MAX1070) 0 -0.1 0 MAX1070/71 toc06 0.75 OFFSET ERROR (LSB) 0.1 DNL (LSB) 0.1 512 1.
PAGE 6
Typical Operating Characteristics (continued) (VDD = +3V, VL = VDD, VREF = 2.048V, fSCLK = 24MHz, fSAMPLE = 1.5Msps, TA = -40°C to +85°C, unless otherwise noted. Typical values are at TA = +25°C.) DYNAMIC PERFORMANCE vs. INPUT FREQUENCY (MAX1071) SNR 61.2 61.1 61.4 61.3 SNR -88 61.1 -90 -92 100 500 200 SFDR vs. INPUT FREQUENCY AMPLITUDE (dB) 86 84 fIN = 500kHz SINAD = 61.2dB SNR = 61.2dB THD = -83.5dB SFDR = 83.
PAGE 7
1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs VL PARTIAL/FULL POWER-DOWN SUPPLY CURRENT vs. TEMPERATURE 0.6 VDD, fSCLK = 24MHz 0.4 VL, NO SCLK VL = 3V, fSCLK = 24MHz 50 VL = 1.8V, fSCLK = 24MHz 25 0 -15 10 35 60 MAX1070/71 toc21 6 3 PARTIAL POWER-DOWN 0 -40 85 -15 10 35 60 85 -40 -15 10 35 60 TEMPERATURE (°C) TEMPERATURE (°C) TEMPERATURE (°C) VDD SUPPLY CURRENT vs. CONVERSION RATE VL SUPPLY CURRENT vs. TEMPERATURE VL SUPPLY CURRENT vs.
PAGE 8
1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs MAX1070/MAX1071 Pin Description PIN NAME FUNCTION 1 AIN- Negative Analog Input 2 REF External Reference Voltage Input. VREF sets the analog input range. Bypass REF with a 0.01µF capacitor and a 4.7µF capacitor to RGND. 3 RGND Reference Ground. Connect RGND to GND. VDD Positive Analog Supply Voltage (+2.7V to 3.6V). Bypass VDD with a 0.01µF capacitor and a 10µF capacitor to GND. 5, 11 N.C. No Connection 6 GND Ground.
PAGE 9
1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs VL CIN+ REF MAX1070/MAX1071 VDD CAPACITIVE DAC RIN+ AIN+ AIN+ 10-BIT SAR ADC T/H AIN- OUTPUT BUFFER CONTROL LOGIC AND TIMING DOUT CNVST VAZ COMP AIN- SCLK CIN- RIN- CIN+ RIN+ ACQUISITION MODE MAX1070 MAX1071 RGND GND CONTROL LOGIC CAPACITIVE DAC AIN+ Figure 3.
PAGE 10
MAX1070/MAX1071 1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs CNVST tSETUP tACQUIRE POWER-MODE SELECTION WINDOW 1 SCLK 2 3 4 HIGH IMPEDANCE 8 D9 DOUT D8 D7 D6 CONTINUOUS-CONVERSION 16 SELECTION WINDOW 14 D5 D4 D3 D2 D1 D0 S1 S0 Figure 5.
PAGE 11
1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs External Reference An external reference is required for the MAX1070/ MAX1071. Use a 4.7µF and 0.01µF bypass capacitor on the REF pin for best performance. The reference input structure allows a voltage range of +1V to VDD. How to Start a Conversion An analog-to-digital conversion is initiated by CNVST and clocked by SCLK, and the resulting data is clocked out on DOUT by SCLK.
PAGE 12
MAX1070/MAX1071 1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs CNVST SCLK 1 14 16 1 DOUT 0 0 0 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 S1 S0 0 Figure 10. Continuous Conversion with Burst/Continuous Clock I/O SCK MISO +3V TO +5V CNVST SCLK DOUT MAX1070 MAX1071 SS A) SPI CS SCK MISO +3V TO +5V CNVST SCLK DOUT MAX1070 MAX1071 SS B) QSPI I/O SK SI CNVST SCLK DOUT MAX1070 MAX1071 C) MICROWIRE Figure 11.
PAGE 13
1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs MAX1070/MAX1071 CNVST 8 1 9 16 SCLK DOUT HIGH-Z D9 D8 D5 D6 D7 D4 D3 D2 D1 S1 D0 HIGH-Z S0 Figure 12. SPI/MICROWIRE Serial-Interface Timing—Single Conversion (CPOL = CPHA = 0), (CPOL = CPHA = 1) CNVST SCLK 14 1 0 DOUT 0 0 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 16 S1 S0 1 0 0 Figure 13.
PAGE 14
MAX1070/MAX1071 1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs VL MAX1070 SCLK MAX1071 CNVST DVDD CLKX TMS320C54_ CLKR DVDD CLKR TMS320C54_ CNVST FSR DOUT DR FSX FSR DOUT VL MAX1070 MAX1071 SCLK DR CLOCK CONVERT Figure 15. Interfacing to the TMS320C54_ Internal Clocks Figure 16. Interfacing to the TMS320C54_ External Clocks For continuous conversion, set the serial port to transmit a clock, and pulse the frame sync signal for a clock period before data transmission.
PAGE 15
1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs MAX1070/MAX1071 CNVST SCLK DOUT 1 S0 0 1 0 0 0 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 S1 S0 0 0 Figure 17. DSP Interface—Continuous Conversion CNVST SCLK DOUT 1 1 0 0 0 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 S1 S0 0 0 0 Figure 18. DSP Interface—Single-Conversion, Continuous/Burst Clock registers should be configured for late framing (LAFR = 1) and for an active-low frame (LTFS = 1, LRFS = 1) signal.
PAGE 16
MAX1070/MAX1071 1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs VL MAX1070 SCLK MAX1071 CNVST SUPPLIES VDDINT TCLK ADSP21_ _ _ RCLK VDD GND VL TFS 10μF RFS 10μF DOUT DR 0.1μF 0.1μF Figure 19. Interfacing to the ADSP21_ _ _ VDD GND RGND VL DGND VL Signal-to-Noise Ratio For a waveform perfectly reconstructed from digital samples, signal-to-noise ratio (SNR) is the ratio of full-scale analog input (RMS value) to the RMS quantization error (residual error).
PAGE 17
1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs Intermodulation Distortion Any device with nonlinearities creates distortion products when two sine waves at two different frequencies (f1 and f2) are input into the device. Intermodulation distortion (IMD) is the total power of the IM2 to IM5 intermodulation products to the Nyquist frequency relative to the total input power of the two input tones, f1 and f2. The individual input tone levels are at -7dBFS.
PAGE 18
MAX1070/MAX1071 1.5Msps, Single-Supply, Low-Power, True-Differential, 10-Bit ADCs Revision History REVISION NUMBER REVISION DATE 0 5/04 Initial release 1 4/09 Removed commercial temperature grade parts from data sheet DESCRIPTION PAGES CHANGED — 1–7 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied.