19-0526; Rev 0; 5/06 KIT ATION EVALU E L B AVAILA 10-Bit, 7.5Msps, Full-Duplex Analog Front-End Applications Portable Communication Equipment MAX19710ETN+ DA4 DA5 DA6 DA7 DA8 DA9 DOUT DIN SCLK VDD CS/WAKE GND VDD 28 DA3 DAC3 44 27 DA2 DAC2 45 26 DA1 DAC1 46 25 DA0 VDD 47 24 OVDD IDN 48 23 OGND 22 AD9 IDP 49 MAX19710 GND 50 21 AD8 VDD 51 20 AD7 QDN 52 19 AD6 QDP 53 18 AD5 17 AD4 EXPOSED PADDLE (GND) COM 55 56 Thin QFN-EP** T5677-1 *All devices are specified over the -40°C to +85°C operating range. **EP = Exposed paddle. +Denotes lead-free package. 7 8 9 10 11 12 13 14 CLK GND VDD QAN QAP AD1 6 AD0 5 GND 4 VDD 3 GND T5677-1 2 IAN PKG CODE 15 AD2 1 IAP PIN-PACKAGE 56 Thin QFN-EP** 16 AD3 REFN 56 VDD PART* 42 41 40 39 38 37 36 35 34 33 32 31 30 29 ADC1 43 REFIN 54 Ordering Information MAX19710ETN TOP VIEW REFP Broadband Access Radio Private Mobile Radio Pin Configuration ADC2 The MAX19710 is an ultra-low-power, highly integrated mixed-signal analog front-end (AFE) ideal for wideband communication applications operating in full-duplex (FD) mode. Optimized for high dynamic performance and ultra-low power, the device integrates a dual 10-bit, 7.5Msps receive (Rx) ADC; dual 10-bit, 7.5Msps transmit (Tx) DAC; three fast-settling 12-bit aux-DAC channels for ancillary RF front-end control; and a 10-bit, 333ksps housekeeping aux-ADC. The typical operating power in FD mode is 30mW at a 7.5MHz clock frequency. The Rx ADCs feature 54.8dB SINAD and 79.8dBc SFDR at 3.3MHz input frequency with a 7.5MHz clock frequency. The analog I/Q input amplifiers are fully differential and accept 1.024VP-P full-scale signals. Typical I/Q channel matching is ±0.01° phase and ±0.01dB gain. The Tx DACs feature 73.8dBc SFDR at fOUT = 620kHz and fCLK = 7.5MHz. The analog I-Q full-scale output voltage range is ±400mV differential. The output DC common-mode voltage is from 0.89V to 1.36V. The I/Q channel offset is adjustable to optimize radio lineup sideband/carrier suppression. Typical I-Q channel matching is ±0.01dB gain and ±0.15° phase. Two independent 10-bit parallel, high-speed digital buses used by the Rx ADC and Tx DAC allow fullduplex operation for frequency-division duplex applications. The Rx ADC and Tx DAC can be disabled independently to optimize power management. A 3-wire serial interface controls power-management modes, the aux-DAC channels, and the aux-ADC channels. The MAX19710 operates on a single 2.7V to 3.3V analog supply and 1.8V to 3.3V digital I/O supply. The MAX19710 is specified for the extended (-40°C to +85°C) temperature range and is available in a 56-pin, thin QFN package. The Selector Guide at the end of the data sheet lists other pin-compatible versions in this AFE family. For time-division duplex (TDD) applications, refer to the MAX19705–MAX19708 AFE family of products. Features ♦ Dual 10-Bit, 7.5Msps Rx ADC and Dual 10-Bit, 7.5Msps Tx DAC ♦ Ultra-Low Power 30mW at fCLK = 7.5MHz, FD Mode 21.3mW at fCLK = 7.5MHz, Slow Rx Mode 21.9mW at fCLK = 7.5MHz, Slow Tx Mode Low-Current Standby and Shutdown Modes ♦ Programmable Tx DAC Common-Mode DC Level and I/Q Offset Trim ♦ Excellent Dynamic Performance SNR = 54.9dB at fIN = 3.3MHz (Rx ADC) SFDR = 73.8dBc at fOUT = 620kHz (Tx DAC) ♦ Three 12-Bit, 1μs Aux-DACs ♦ 10-Bit, 333ksps Aux-ADC with 4:1 Input Mux and Data Averaging ♦ Excellent Gain/Phase Match ±0.01° Phase, ±0.01dB Gain (Rx ADC) at fIN = 1.8MHz ♦ Multiplexed Parallel Digital I/O ♦ Serial-Interface Control ♦ Versatile Power-Control Circuits Shutdown, Standby, Idle, Tx/Rx Disable ♦ Miniature 56-Pin Thin QFN Package (7mm x 7mm x 0.8mm) THIN QFN NOTE: THE PIN 1 INDICATOR IS “+” FOR LEAD-FREE DEVICES. Functional Diagram and Selector Guide appear at end of data sheet. ________________________________________________________________ Maxim Integrated Products For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com. 1 MAX19710 General Description MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End ABSOLUTE MAXIMUM RATINGS VDD to GND, OVDD to OGND ..............................-0.3V to +3.6V GND to OGND.......................................................-0.3V to +0.3V IAP, IAN, QAP, QAN, IDP, IDN, QDP, QDN, DAC1, DAC2, DAC3 to GND .....................-0.3V to VDD ADC1, ADC2 to GND.................................-0.3V to (VDD + 0.3V) REFP, REFN, REFIN, COM to GND ...........-0.3V to (VDD + 0.3V) AD0–AD9, DA0–DA9, SCLK, DIN, CS/WAKE, CLK, DOUT to OGND .........................-0.3V to (OVDD + 0.3V) Continuous Power Dissipation (TA = +70°C) 56-Pin Thin QFN-EP (derate 27.8mW/°C above +70°C) 2.22W Thermal Resistance θJA ..................................................36°C/W Operating Temperature Range ...........................-40°C to +85°C Junction Temperature ......................................................+150°C Storage Temperature Range .............................-60°C to +150°C Lead Temperature (soldering, 10s) .................................+300°C 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 in the operational sections of the specifications is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability. ELECTRICAL CHARACTERISTICS (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, CL < 5pF on all aux-DAC outputs, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP 3.0 MAX UNITS POWER REQUIREMENTS Analog Supply Voltage VDD 2.7 Output Supply Voltage OVDD 1.8 3.3 V VDD V FD mode: fCLK = 7.5MHz, fOUT = 620kHz on both DAC channels; fIN = 1.875MHz on both ADC channels; aux-DACs ON and at midscale, aux-ADC ON 10 12 SPI2-Tx mode: fCLK = 7.5MHz, fOUT = 620kHz on both DAC channels; Rx ADC OFF; aux-DACs ON and at midscale, auxADC ON 7.3 9 VDD Supply Current 2 mA SPI1-Rx mode: fCLK = 7.5MHz, fIN = 1.875MHz on both ADC channels; Tx DAC OFF (Tx DAC outputs at 0V); aux-DACs ON and at midscale, aux-ADC ON 7.1 9 SPI4-Tx mode: fCLK = 7.5MHz, fOUT = 620kHz on both DAC channels; Rx ADC ON (output tri-stated); aux-DACs ON and at midscale, aux-ADC ON 9.7 12 _______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, CL < 5pF on all aux-DAC outputs, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL VDD Supply Current OVDD Supply Current CONDITIONS MIN TYP MAX SPI3-Rx mode: fCLK = 7.5MHz, fIN = 1.875MHz on both channels; Tx DAC ON (Tx DAC outputs at midscale); aux-DACs ON and at midscale, aux-ADC ON 9.5 12 Standby mode: CLK = 0 or OVDD; aux-DACs ON and at midscale, aux-ADC ON 2.7 3.5 Idle mode: fCLK = 7.5MHz; aux-DACs ON and at midscale, aux-ADC ON 4.6 6 Shutdown mode: CLK = 0 or OVDD, or aux-ADC OFF 0.5 5 FD mode: fCLK = 7.5MHz, fOUT = 620kHz on both DAC channels; fIN = 1.875MHz on both ADC channels; aux-DACs ON and at midscale, aux-ADC ON 0.94 UNITS mA µA mA SPI1-Rx and SPI3-Rx modes: fCLK = 7.5MHz, fIN = 1.875MHz on both ADC channels; DAC input bus tri-stated; auxDACs ON and at midscale, aux-ADC ON 0.90 SPI2-Tx and SPI4-Tx modes: fCLK = 7.5MHz, fOUT = 620kHz on both DAC channels; ADC output bus tri-stated; auxDACs ON and at midscale, aux-ADC ON 52 Standby mode: CLK = 0 or OVDD; auxDACs ON and at midscale, aux-ADC ON 0.1 Idle mode: fCLK = 7.5MHz; aux-DACs ON and at midscale, aux-ADC ON 12.8 Shutdown mode: CLK = 0 or OVDD, or aux-ADC OFF 0.1 µA Rx ADC DC ACCURACY Resolution N Integral Nonlinearity INL Differential Nonlinearity DNL 10 Bits ±0.5 -0.8 ±0.4 +1.0 LSB Offset Error Residual DC offset error -5 ±0.2 +5 %FS Gain Error Includes reference error -5 ±0.9 +5 %FS -0.15 ±0.04 +0.15 DC Gain Matching Offset Matching No missing codes over temperature (Note 2) LSB ±11 dB LSB _______________________________________________________________________________________ 3 MAX19710 ELECTRICAL CHARACTERISTICS (continued) MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End ELECTRICAL CHARACTERISTICS (continued) (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, CL < 5pF on all aux-DAC outputs, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN Gain Temperature Coefficient Power-Supply Rejection TYP MAX ±30 PSRR UNITS ppm/°C Offset (VDD ±5%) ±0.2 Gain (VDD ±5%) ±0.05 Differential or single-ended inputs ±0.512 V VDD / 2 V 720 kΩ 5 pF LSB Rx ADC ANALOG INPUT Input Differential Range VID Input Common-Mode Voltage Range VCM Input Impedance RIN Switched capacitor load CIN Rx ADC CONVERSION RATE Maximum Clock Frequency fCLK Data Latency (Note 3) 7.5 Channel IA 5 Channel QA 5.5 MHz Clock Cycles Rx ADC DYNAMIC CHARACTERISTICS (Note 4) Signal-to-Noise Ratio SNR fIN = 1.875MHz 53.2 fIN = 3.3MHz fIN = 1.875MHz 54.8 dB 54.9 53.1 54.7 Signal-to-Noise and Distortion SINAD Spurious-Free Dynamic Range SFDR Total Harmonic Distortion THD Third-Harmonic Distortion HD3 Intermodulation Distortion IMD fIN1 = 1.8MHz, AIN1 = -7dBFS; fIN2 = 1MHz, AIN2 = -7dBFS -72 dBc Third-Order Intermodulation Distortion IM3 fIN1 = 1.8MHz, AIN1 = -7dBFS; fIN2 = 1MHz, AIN2 = -7dBFS -83 dBc fIN = 3.3MHz fIN = 1.875MHz dB 54.8 64.2 73.9 fIN = 3.3MHz 79.8 fIN = 1.875MHz -71.7 fIN = 3.3MHz -74.3 fIN = 1.875MHz -76.8 fIN = 3.3MHz -83.8 dBc -62.8 dBc dBc Aperture Delay 3.5 ns Aperture Jitter 2 psRMS 2 ns -91 dB Overdrive Recovery Time 1.5x full-scale input Rx ADC INTERCHANNEL CHARACTERISTICS Crosstalk Rejection fINX,Y = 1.8MHz, AINX,Y = -0.5dBFS, fINY,X = 1MHz, AINY,X = -0.5dBFS (Note 5) Amplitude Matching fIN = 1.8MHz, AIN = -0.5dBFS (Note 6) ±0.01 dB Phase Matching fIN = 1.8MHz, AIN = -0.5dBFS (Note 6) ±0.01 Degrees 4 _______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, CL < 5pF on all aux-DAC outputs, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS Tx DAC DC ACCURACY Resolution N Integral Nonlinearity INL Differential Nonlinearity Residual DC Offset DNL VOS 10 Bits ±0.3 Guaranteed monotonic (Note 2) Full-Scale Gain Error LSB -0.75 -4 ±0.2 ±1.2 +0.75 +4 LSB mV -40 ±1.6 +40 mV 7.5 MHz Tx DAC DYNAMIC PERFORMANCE DAC Conversion Rate fCLK (Note 3) In-Band Noise Density ND fOUT = 620kHz -120 dBFS/Hz Third-Order Intermodulation Distortion IM3 fOUT1 = 620kHz, fOUT2 = 640kHz -79 dBc 10 pV•s 73.8 dBc Glitch Impulse Spurious-Free Dynamic Range to Nyquist SFDR fOUT = 620kHz Total Harmonic Distortion to Nyquist THD fOUT = 620kHz -72.2 Signal-to-Noise Ratio to Nyquist SNR fOUT = 620kHz 55.1 dB 92 dB 61 -59.7 dBc Tx DAC INTERCHANNEL CHARACTERISTICS I-to-Q Output Isolation fOUTX,Y = 2MHz, fOUTY,X = 2.2MHz Gain Mismatch Between I and Q Channels Measured at DC Phase Mismatch Between I and Q Channels fOUT = 620kHz -0.4 Differential Output Impedance ±0.01 +0.4 dB ±0.15 Degrees 800 Ω Tx DAC ANALOG OUTPUT Full-Scale Output Voltage Output Common-Mode Voltage VFS VCOMD ±400 Bits CM1 = 0, CM0 = 0 (default) 1.29 Bits CM1 = 0, CM0 = 1 Bits CM1 = 1, CM0 = 0 Bits CM1 = 1, CM0 = 1 mV 1.36 1.42 1.14 1.2 1.27 0.96 1.05 1.15 0.78 0.89 1.03 V Rx ADC–Tx DAC INTERCHANNEL CHARACTERISTICS ADC fINI = fINQ = 1.8MHz, DAC fOUTI = fOUTQ = 620kHz Receive Transmit Isolation AUXILIARY ADCs (ADC1, ADC2) Resolution N 92 10 dB Bits _______________________________________________________________________________________ 5 MAX19710 ELECTRICAL CHARACTERISTICS (continued) MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End ELECTRICAL CHARACTERISTICS (continued) (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, CL < 5pF on all aux-DAC outputs, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER Full-Scale Reference SYMBOL VREF CONDITIONS MIN AD1 = 0 (default) TYP MAX 2.048 AD1 = 1 V VDD Analog Input Range UNITS 0 to VREF V Analog Input Impedance Measured at DC 500 kΩ Input-Leakage Current Measured at unselected input from 0 to VREF ±0.1 µA Gain Error GE Zero-Code Error ZE Includes reference error, AD1 = 0 -5 ±2 mV Differential Nonlinearity DNL ±0.6 LSB Integral Nonlinearity INL ±0.6 LSB 210 µA ±1.25 LSB Supply Current +5 %FS AUXILIARY DACs (DAC1, DAC2, DAC3) Resolution N 12 Integral Nonlinearity INL From code 100 to code 4000 Differential Nonlinearity DNL Guaranteed monotonic over code 100 to code 4000 (Note 2) Output-Voltage Low VOL RL > 200kΩ Output-Voltage High VOH RL > 200kΩ -1.0 Bits ±0.65 +1.2 0.2 2.57 LSB V V DC Output Impedance DC output at midscale 4 Ω Settling Time From code 1024 to code 3072, within ±10 LSB 1 µs Glitch Impulse From code 0 to code 4095 24 nV•s Rx ADC–Tx DAC TIMING CHARACTERISTICS CLK Rise to Channel-I Output Data Valid tDOI Figure 3 (Note 2) 5.5 8.2 11.5 ns CLK Fall to Channel-Q Output Data Valid tDOQ Figure 3 (Note 2) 6.5 9.3 13.0 ns I-DAC DATA to CLK Fall Setup Time tDSI Figure 5 (Note 2) 10 ns Q-DAC DATA to CLK Rise Setup Time tDSQ Figure 5 (Note 2) 10 ns CLK Fall to I-DAC Data Hold Time tDHI Figure 5 (Note 2) 0 ns CLK Rise to Q-DAC Data Hold Time tDHQ Figure 5 (Note 2) 0 ns CLK Duty Cycle CLK Duty-Cycle Variation Digital Output Rise/Fall Time 6 20% to 80% 50 % ±15 % 2.4 ns _______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, CL < 5pF on all aux-DAC outputs, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS SERIAL-INTERFACE TIMING CHARACTERISTICS (Figures 6 and 8, Note 2) Falling Edge of CS/WAKE to Rising Edge of First SCLK Time tCSS 10 DIN to SCLK Setup Time tDS 10 ns DIN to SCLK Hold Time tDH 0 ns SCLK Pulse-Width High tCH 25 ns SCLK Pulse-Width Low tCL 25 ns SCLK Period tCP 50 ns SCLK to CS/WAKE Setup Time tCS 10 ns CS/WAKE High Pulse Width tCSW 80 ns CS/WAKE High to DOUT Active High tCSD CS/WAKE High to DOUT Low (Aux-ADC Conversion Time) tCONV ns Bit AD0 set 200 ns Bit AD0 set, no averaging, fCLK = 7.5MHz, CLK divider = 2 4.3 µs 200 ns DOUT Low to CS/WAKE Setup Time tDCS Bit AD0, AD10 set SCLK Low to DOUT Data Out tCD Bit AD0, AD10 set CS/WAKE High to DOUT High Impedance tCHZ Bit AD0, AD10 set 14.5 200 ns ns MODE-RECOVERY TIMING CHARACTERISTICS (Figure 7) Shutdown Wake-Up Time (With CLK) Idle Wake-Up Time (With CLK) tWAKE,SD tWAKE,ST0 From shutdown to Rx mode, ADC settles to within 1dB SINAD 500 From shutdown to Tx mode, DAC settles to within 10 LSB error 26.2 From aux-ADC enable to aux-ADC start conversion 10 From shutdown to aux-DAC output valid 28 From shutdown to FD mode, ADC settles to within 1dB SINAD, DAC settles to within 10 LSB error 500 From idle to Rx mode, ADC settles to within 1dB SINAD 7.3 From idle to Tx mode, DAC settles to 10 LSB error 5.2 From idle to FD mode, ADC settles to within 1dB SINAD, DAC settles to within 10 LSB error 7.3 µs µs _______________________________________________________________________________________ 7 MAX19710 ELECTRICAL CHARACTERISTICS (continued) MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End ELECTRICAL CHARACTERISTICS (continued) (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, CL < 5pF on all aux-DAC outputs, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER Standby Wake-Up Time (With CLK) SYMBOL tWAKE,ST1 CONDITIONS MIN TYP From standby to Rx mode, ADC settles to within 1dB SINAD 7.5 From standby to Tx mode, DAC settles to 10 LSB error 22.2 From standby to FD mode, ADC settles to within 1dB SINAD, DAC settles to within 10 LSB error 22.2 MAX UNITS µs Enable Time from Tx to Rx, Fast Mode tENABLE,RX ADC settles to within 1dB SINAD 0.1 µs Enable Time from Rx to Tx, Fast Mode tENABLE,TX DAC settles to within 10 LSB error 0.1 µs Enable Time from Tx to Rx, Slow Mode tENABLE,RX ADC settles to within 1dB SINAD 7.3 µs Enable Time from Rx to Tx, Slow Mode tENABLE,TX DAC settles to within 10 LSB error 5.2 µs 0.256 V INTERNAL REFERENCE (VREFIN = VDD; VREFP, VREFN, VCOM levels are generated internally) Positive Reference VREFP - VCOM Negative Reference VREFN - VCOM -0.256 V VCOM VDD / 2 VDD / 2 VDD / 2 - 0.15 + 0.15 V Maximum REFP/REFN/COM Source Current ISOURCE 2 mA Maximum REFP/REFN/COM Sink Current ISINK 2 mA Differential Reference Output VREF Common-Mode Output Voltage Differential Reference Temperature Coefficient VREFP - VREFN REFTC +0.490 +0.512 ±30 +0.534 V ppm/°C BUFFERED EXTERNAL REFERENCE (external VREFIN = 1.024V applied; VREFP, VREFN, VCOM levels are generated internally) Reference Input Voltage VREFIN 1.024 VREFP - VREFN V Differential Reference Output VDIFF 0.512 V Common-Mode Output Voltage VCOM VDD / 2 V Maximum REFP/REFN/COM Source Current ISOURCE 2 mA Maximum REFP/REFN/COM Sink Current ISINK 2 mA REFIN Input Current -0.7 µA REFIN Input Resistance 500 kΩ 8 _______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, CL < 5pF on all aux-DAC outputs, TA = TMIN to TMAX, unless otherwise noted. Typical values are at TA = +25°C.) (Note 1) PARAMETER SYMBOL CONDITIONS MIN TYP MAX UNITS DIGITAL INPUTS (CLK, SCLK, DIN, CS/WAKE, DA9–DA0) Input High Threshold VINH Input Low Threshold VINL Input Leakage DIIN Input Capacitance 0.7 x OVDD V 0.3 x OVDD CLK, SCLK, DIN, CS/WAKE = OGND or OVDD -1 +1 DA9–DA0 = OVDD -1 +1 DA9–DA0 = OGND -5 +5 DCIN 5 V µA pF DIGITAL OUTPUTS (AD9–AD0, DOUT) Output-Voltage Low VOL ISINK = 200µA Output-Voltage High VOH ISOURCE = 200µA Tri-State Leakage Current ILEAK Tri-State Output Capacitance COUT 0.2 x OVDD 0.8 x OVDD V V -1 +1 5 µA pF Note 1: Specifications from TA = +25°C to +85°C guaranteed by production tests. Specifications at TA < +25°C guaranteed by design and characterization. Note 2: Guaranteed by design and characterization. Note 3: The minimum clock frequency (fCLK) for the MAX19710 is 1.5MHz (typ). The minimum aux-ADC sample rate clock frequency (ACLK) is determined by fCLK and the chosen aux-ADC clock-divider value. The minimum aux-ADC ACLK > 1.5MHz / 128 = 11.7kHz. The aux-ADC conversion time does not include the time to clock the serial data out of DOUT. The maximum conversion time (for no averaging, NAVG = 1) will be tCONV (max) = (12 x 1 x 128) / 1.5MHz = 1024µs. Note 4: SNR, SINAD, SFDR, HD3, and THD are based on a differential analog input voltage of -0.5dBFS referenced to the amplitude of the digital outputs. SINAD and THD are calculated using HD2 through HD6. Note 5: Crosstalk rejection is measured by applying a high-frequency test tone to one channel and a low-frequency tone to the second channel. FFTs are performed on each channel. The parameter is specified as the power ratio of the first and second channel FFT test tones. Note 6: Amplitude and phase matching are measured by applying the same signal to each channel, and comparing the two output signals using a sine-wave fit. _______________________________________________________________________________________ 9 MAX19710 ELECTRICAL CHARACTERISTICS (continued) Typical Operating Characteristics (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, TA = +25°C, unless otherwise noted.) -50 -60 5 4 6 2 3 -40 -60 3 -70 -80 -90 -90 2 5 4 6 1.0 1.5 2.0 2.5 3.0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 0 57 MAX19710 toc04 fIN2 56 IA 56 -100 54 QA 53 MAX19710 toc03 3.0 3.5 1.5 2.0 2.5 3.0 51 3.5 50 0 90 MAX19710 toc07 85 0 10 20 30 40 50 60 70 80 90 100 ANALOG INPUT FREQUENCY (MHz) 10 20 30 40 50 60 70 80 90 100 ANALOG INPUT FREQUENCY (MHz) Rx ADC SPURIOUS-FREE DYNAMIC RANGE vs. ANALOG INPUT FREQUENCY Rx ADC TOTAL HARMONIC DISTORTION vs. ANALOG INPUT FREQUENCY 90 QA 51 85 IA 80 Rx ADC SIGNAL-T0-NOISE RATIO vs. ANALOG INPUT AMPLITUDE 60 MAX19710 toc08 1.0 IA 53 52 FREQUENCY (MHz) 55 QA QA 75 45 70 QA SNR (dB) SFDR (dBc) 70 40 65 35 60 60 30 55 55 25 50 50 10 20 30 40 50 60 70 80 90 100 ANALOG INPUT FREQUENCY (MHz) fIN = 1.875MHz 50 IA 75 0 2.5 54 52 50 65 2.0 55 SINAD (dB) SNR (dB) 2fIN2 - fIN1 -90 80 1.5 57 55 2fIN1 - fIN2 0.5 1.0 Rx ADC SIGNAL-TO-NOISE AND DISTORTION RATIO vs. ANALOG INPUT FREQUENCY -60 0 0.5 Rx ADC SIGNAL-TO-NOISE RATIO vs. ANALOG INPUT FREQUENCY -50 -80 2fIN2 - fIN1 Rx ADC CHANNEL-QA TWO-TONE FFT PLOT fIN1 = 1.7471383MHz fIN2 = 1.8421213MHz AIN1 = AIN2 = -7dBFS IMD = -64dBc -70 2fIN1 - fIN2 FREQUENCY (MHz) -20 -40 -70 FREQUENCY (MHz) fIN1 -30 -60 FREQUENCY (MHz) 0 -10 -50 -100 0 3.5 -40 -90 MAX19710 toc05 0.5 fIN2 fIN1 = 1.7471383MHz fIN2 = 1.8421213MHz AIN1 = AIN2 = -7dBFS IMD = -64dBc -30 -80 -100 0 10 MAX19710 toc02 -50 -80 -100 AMPLITUDE (dBFS) -30 fIN1 -20 MAX19710 toc06 -70 -20 0 -10 MAX19710 toc09 -40 FUNDAMENTAL fIN = 1.8019362MHz AIN = -0.488dBFS SINAD = 54.773dB SNR = 54.83dB THD = -73.651dBc SFDR = 77.541dBc AMPLITUDE (dBFS) -30 0 -10 AMPLITUDE (dBFS) -20 AMPLITUDE (dBFS) FUNDAMENTAL fIN = 1.8019362MHz AIN = -0.524dBFS SINAD = 54.897dB SNR = 54.927dB THD = -76.609dBc SFDR = 83.379dBc MAX19710 toc01 0 -10 Rx ADC CHANNEL-IA TWO-TONE FFT PLOT Rx ADC CHANNEL-QA FFT PLOT Rx ADC CHANNEL-IA FFT PLOT -THD (dBc) MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End IA 20 0 10 20 30 40 50 60 70 80 90 100 ANALOG INPUT FREQUENCY (MHz) -30 -25 -20 -15 -10 -5 ANALOG INPUT AMPLITUDE (dBFS) ______________________________________________________________________________________ 0 10-Bit, 7.5Msps, Full-Duplex Analog Front-End (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, TA = +25°C, unless otherwise noted.) 65 40 IA 60 55 SFDR (dBc) 45 QA 50 45 30 40 25 30 -30 0 fIN = 1.875MHz IA 56.0 55.5 55.5 55.0 55.0 54.5 QA 54.0 53.5 53.0 52.5 52.5 IA -25 -20 -15 -10 -5 ANALOG INPUT AMPLITUDE (dBFS) 0 Rx ADC TOTAL HARMONIC DISTORTION vs. SAMPLING FREQUENCY 85 fIN = 1.875MHz IA 80 75 QA 70 QA 65 60 55 52.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 SAMPLING FREQUENCY (MHz) 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 SAMPLING FREQUENCY (MHz) Rx ADC SPURIOUS-FREE DYNAMIC RANGE vs. SAMPLING FREQUENCY Rx ADC SIGNAL-TO-NOISE RATIO vs. CLOCK DUTY CYCLE Rx ADC SIGNAL-TO-NOISE AND DISTORTION RATIO vs. CLOCK DUTY CYCLE 85 58 fIN = 1.875MHz 57 80 56 IA 55 54 65 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 SAMPLING FREQUENCY (MHz) 55 QA 53 52 55 IA 54 QA 53 60 fIN = 1.875MHz 57 SINAD (dB) QA SNR (dB) 56 75 58 MAX19710 toc17 IA MAX19710 toc16 fIN = 1.875MHz MAX19710 toc18 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 SAMPLING FREQUENCY (MHz) 90 SFDR (dBc) IA 54.0 53.0 52.0 QA -30 54.5 53.5 70 fIN = 1.875MHz 56.5 SINAD (dB) SNR (dB) 56.0 57.0 MAX19710 toc13 56.5 0 Rx ADC SIGNAL-TO-NOISE AND DISTORTION RATIO vs. SAMPLING FREQUENCY Rx ADC SIGNAL-TO-NOISE RATIO vs. SAMPLING FREQUENCY 57.0 -25 -20 -15 -10 -5 ANALOG INPUT AMPLITUDE (dBFS) -THD (dBc) -25 -20 -15 -10 -5 ANALOG INPUT AMPLITUDE (dBFS) MAX19710 toc14 -30 fIN = 1.875MHz 40 35 30 35 20 90 85 80 75 70 65 60 55 50 45 MAX19710 toc12 IA 70 -THD (dBc) SINAD (dB) 75 QA 35 fIN = 1.875MHz MAX19710 toc15 55 MAX19710 toc11 fIN = 1.875MHz 50 80 MAX19710 toc10 60 Rx ADC SPURIOUS-FREE DYNAMIC RANGE vs. ANALOG INPUT AMPLITUDE Rx ADC TOTAL HARMONIC DISTORTION vs. ANALOG INPUT AMPLITUDE Rx ADC SIGNAL-TO-NOISE AND DISTORTION RATIO vs. ANALOG INPUT AMPLITUDE 52 35 40 45 50 55 60 CLOCK DUTY CYCLE (%) 65 35 40 45 50 55 60 CLOCK DUTY CYCLE (%) ______________________________________________________________________________________ 65 11 MAX19710 Typical Operating Characteristics (continued) Typical Operating Characteristics (continued) (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, TA = +25°C, unless otherwise noted.) 75 80 70 SFDR (dBc) QA 65 60 75 QA 70 55 0.75 0.25 QA 0 -0.25 -0.50 50 65 -1.00 60 40 40 45 50 55 60 CLOCK DUTY CYCLE (%) 35 65 -40 65 90 MAX19710 toc22 1.75 45 50 55 60 CLOCK DUTY CYCLE (%) Tx DAC SPURIOUS-FREE DYNAMIC RANGE vs. SAMPLING FREQUENCY Rx ADC GAIN ERROR vs. TEMPERATURE 2.00 40 fOUT = fCLK / 10 85 QD 1.50 -15 10 35 TEMPERATURE (°C) 60 85 Tx DAC SPURIOUS-FREE DYNAMIC RANGE vs. OUTPUT FREQUENCY 90 MAX19710 toc23 35 IA -0.75 45 85 QD 80 QA 1.00 0.75 SFDR (dBc) 80 1.25 SFDR (dBc) 75 ID 70 IA 55 0 -40 -15 10 35 TEMPERATURE (°C) 60 60 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 SAMPLING FREQUENCY (MHz) 85 Tx DAC SPURIOUS-FREE DYNAMIC RANGE vs. OUTPUT AMPLITUDE 80 70 60 ID 50 fOUT = 2.2MHz -10 -20 AMPLITUDE (dBFS) QD Tx DAC CHANNEL-QD SPECTRAL PLOT 0 -30 -40 -50 -60 fOUT = 2.2MHz -10 -20 AMPLITUDE (dBFS) fOUT = 2MHz 0.2 0.6 1.0 1.4 1.8 2.2 2.6 3.0 3.4 3.8 OUTPUT FREQUENCY (MHz) Tx DAC CHANNEL-ID SPECTRAL PLOT 0 MAX19710 toc25 90 ID 65 60 0.25 75 70 65 0.50 MAX19710 toc26 GAIN ERROR (%FS) 0.50 MAX19710 toc27 -THD (dBc) IA 85 MAX19710 toc21 80 fIN = 1.875MHz OFFSET ERROR (%FS) IA Rx ADC OFFSET ERROR vs. TEMPERATURE 1.00 MAX19710 toc20 fIN = 1.875MHz 85 90 MAX19710 toc19 90 Rx ADC SPURIOUS-FREE DYNAMIC RANGE vs. CLOCK DUTY CYCLE MAX19710 toc24 Rx ADC TOTAL HARMONIC DISTORTION vs. CLOCK DUTY CYCLE SFDR (dBc) MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End -30 -40 -50 -60 -70 -70 -80 -80 40 -30 12 -90 -90 30 -25 -20 -15 -10 -5 OUTPUT AMPLITUDE (dBFS) 0 0 0.76 1.52 2.28 FREQUENCY (MHz) 3.04 3.80 0 0.76 1.52 2.28 FREQUENCY (MHz) ______________________________________________________________________________________ 3.04 3.80 10-Bit, 7.5Msps, Full-Duplex Analog Front-End -50 -60 9.0 -30 IVDD (mA) -40 -40 -50 -70 -80 -80 8.5 8.0 -60 -70 FD MODE fIN = 1.875MHz fOUT = 620kHz 9.5 MAX1910 toc30 -20 AMPLITUDE (dBFS) -30 fOUT1 = 600kHz, fOUT2 = 800kHz -10 10.0 MAX19710 toc29 fOUT1 = 600kHz, fOUT2 = 800kHz -20 AMPLITUDE (dBFS) 0 MAX19710 toc28 0 -10 SUPPLY CURRENT vs. SAMPLING FREQUENCY Tx DAC CHANNEL-QD TWO-TONE SPECTRAL PLOT Tx DAC CHANNEL-ID TWO-TONE SPECTRAL PLOT 7.5 7.0 -90 -90 1.52 2.28 FREQUENCY (MHz) 3.04 0 3.80 Rx ADC INTEGRAL NONLINEARITY 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 SAMPLING FREQUENCY (MHz) 3.80 Tx DAC INTEGRAL NONLINEARITY MAX19710 toc32 0.8 0.75 0.6 0.50 0.4 0.25 0.25 0.2 0 INL (LSB) 0.50 0 0 -0.25 -0.2 -0.50 -0.50 -0.4 -0.75 -0.75 -0.6 -0.25 -1.00 -0.8 -1.00 128 256 384 512 640 768 896 1024 DIGITAL OUTPUT CODE 0 REFERENCE OUTPUT VOLTAGE vs. TEMPERATURE Tx DAC DIFFERENTIAL NONLINEARITY 0.520 MAX19710 toc34 0.5 0.4 0.3 0 128 256 384 512 640 768 896 1024 DIGITAL OUTPUT CODE VREFP - VREFN AUX-DAC INTEGRAL NONLINEARITY 1.5 1.0 VREFP - VREFN (V) 0.1 0 -0.1 -0.2 INL (LSB) 0.515 0.2 0.510 0.5 0 -0.5 -1.0 0.505 -0.3 128 256 384 512 640 768 896 1024 DIGITAL INPUT CODE 2.0 MAX19710 toc35 0 DNL (LSB) 3.04 Rx ADC DIFFERENTIAL NONLINEARITY DNL (LSB) INL (LSB) 0.75 1.52 2.28 FREQUENCY (MHz) 1.00 MAX19710 toc31 1.00 0.76 MAX19710 toc33 0.76 MAX19710 toc36 0 -1.5 -0.4 -0.5 -2.0 0.500 0 128 256 384 512 640 768 896 1024 DIGITAL INPUT CODE -40 -15 10 35 TEMPERATURE (°C) 60 85 0 512 1024 1536 2048 2560 3072 3584 4096 DIGITAL INPUT CODE ______________________________________________________________________________________ 13 MAX19710 Typical Operating Characteristics (continued) (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, TA = +25°C, unless otherwise noted.) Typical Operating Characteristics (continued) (VDD = 3V, OVDD = 1.8V, internal reference (1.024V), CL ≈ 10pF on all digital outputs, fCLK = 7.5MHz (50% duty cycle), Rx ADC input amplitude = -0.5dBFS, Tx DAC output amplitude = 0dBFS, CM1 = 0, CM0 = 0, differential Rx ADC input, differential Tx DAC output, CREFP = CREFN = CCOM = 0.33µF, TA = +25°C, unless otherwise noted.) AUX-DAC DIFFERENTIAL NONLINEARITY AUX-ADC INTEGRAL NONLINEARITY 0.8 0.6 1.5 1.0 0.4 0.2 0.5 INL (LSB) DNL (LSB) MAX19710 toc38 2.0 MAX19710 toc37 1.0 0 -0.2 0 -0.5 -0.4 -1.0 -0.6 -1.5 -0.8 -1.0 -2.0 512 1024 1536 2048 2560 3072 3584 4096 0 DIGITAL INPUT CODE AUX-DAC OUTPUT VOLTAGE vs. OUTPUT SOURCE CURRENT AUX-ADC DIFFERENTIAL NONLINEARITY 0.6 2.5 OUTPUT VOLTAGE (V) 0.4 DNL (LSB) 3.0 MAX19710 toc39 0.8 128 256 384 512 640 768 896 1024 DIGITAL OUTPUT CODE 0.2 0 -0.2 MAX19710 toc40 0 2.0 1.5 1.0 -0.4 0.5 -0.6 -0.8 0 128 256 384 512 640 768 896 1024 DIGITAL OUTPUT CODE 0 0.001 0.01 0.1 1 AUX-DAC SETTLING TIME MAX19710 toc41 2.5 2.0 STEP FROM CODE 1024 TO CODE 3072 1V/div CS/WAKE 500mV/div 1.5 1.0 AUX-DAC OUTPUT 0.5 14 100 MAX19710 toc42 3.0 0 0.001 10 OUTPUT SOURCE CURRENT (mA) AUX-DAC OUTPUT VOLTAGE vs. OUTPUT SINK CURRENT OUTPUT VOLTAGE (V) MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End 0.01 0.1 1 10 OUTPUT SINK CURRENT (mA) 100 400ns/div ______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End PIN NAME FUNCTION 1 REFP Positive Reference Voltage Input Terminal. Bypass with a 0.33µF capacitor to GND as close to REFP as possible. 2, 8, 11, 39, 41, 47, 51 VDD Analog Supply Voltage. Bypass VDD to GND with a combination of a 2.2µF capacitor in parallel with a 0.1µF capacitor. 3 IAP Channel-IA Positive Analog Input. For single-ended operation, connect signal source to IAP. Channel-IA Negative Analog Input. For single-ended operation, connect IAN to COM. 4 IAN 5, 7, 12, 40, 50 GND Analog Ground. Connect all GND pins to ground plane. 6 CLK Conversion Clock Input. Clock signal for both receive ADCs and transmit DACs. 9 QAN Channel-QA Negative Analog Input. For single-ended operation, connect QAN to COM. 10 QAP Channel-QA Positive Analog Input. For single-ended operation, connect signal source to QAP. 13–22 AD0–AD9 23 OGND Output-Driver Ground 24 OVDD Output-Driver Power Supply. Supply range from +1.8V to VDD. Bypass OVDD to OGND with a combination of a 2.2µF capacitor in parallel with a 0.1µF capacitor. 25–34 DA0–DA9 35 DOUT Receive ADC Digital Outputs. AD9 is the most significant bit (MSB) and AD0 is the least significant bit (LSB). Transmit DAC Digital Inputs. DA9 is the most significant bit (MSB) and DA0 is the least significant bit (LSB). DA0–DA9 are internally pulled up to OVDD. Aux-ADC Digital Output 36 DIN 37 SCLK 3-Wire Serial-Interface Data Input. Data is latched on the rising edge of SCLK. 38 CS/WAKE 42 ADC2 Selectable Auxiliary ADC Analog Input 2 43 ADC1 Selectable Auxiliary ADC Analog Input 1 44 DAC3 Auxiliary DAC3 Analog Output (VOUT = 0 at Power-Up) 45 DAC2 Auxiliary DAC2 Analog Output (VOUT = 0 at Power-Up) 46 DAC1 48 IDN Tx Path Channel-ID Differential Negative Output 49 IDP Tx Path Channel-ID Differential Positive Output 52 QDN Tx Path Channel-QD Differential Negative Output 53 QDP Tx Path Channel-QD Differential Positive Output 54 REFIN Reference Input. Connect to VDD for internal reference. 55 COM Common-Mode Voltage I/O. Bypass COM to GND with a 0.33µF capacitor. 56 REFN Negative Reference Voltage Input Terminal. Rx ADC conversion range is ±(VREFP - VREFN). Bypass REFN to GND with a 0.33µF capacitor. — EP 3-Wire Serial-Interface Clock Input 3-Wire Serial-Interface Chip-Select/WAKE Input. When the MAX19710 is in shutdown, CS/WAKE controls the wake-up function. See the Wake-Up Function section. Auxiliary DAC1 Analog Output (AFC DAC, VOUT = 1.1V at Power-Up) Exposed Paddle. Exposed paddle is internally connected to GND. Connect EP to the GND plane. Detailed Description The MAX19710 integrates a dual, 10-bit Rx ADC and a dual, 10-bit Tx DAC while providing ultra-low power and high dynamic performance at 7.5Msps conversion rate. The Rx ADC analog input amplifiers are fully differ- ential and accept 1.024VP-P full-scale signals. The Tx DAC analog outputs are fully differential with ±400mV full-scale output, selectable common-mode DC level, and adjustable channel ID–QD offset trim. ______________________________________________________________________________________ 15 MAX19710 Pin Description MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End The MAX19710 integrates three 12-bit auxiliary DACs (aux-DACs) and a 10-bit, 333ksps auxiliary ADC (auxADC) with 4:1 input multiplexer. The aux-DAC channels feature 1µs settling time for fast AGC, VGA, and AFC level setting. The aux-ADC features data averaging to reduce processor overhead and a selectable clockdivider to program the conversion rate. MAX19710 operates from a single 2.7V to 3.3V analog supply and a 1.8V to 3.3V digital supply. Dual 10-Bit Rx ADC The ADC uses a seven-stage, fully differential, pipelined architecture that allows for high-speed conversion while minimizing power consumption. Samples taken at the inputs move progressively through the pipeline stages every half clock cycle. Including the delay through the output latch, the total clock-cycle latency is 5 clock cycles for channel IA and 5.5 clock cycles for channel QA. The ADC full-scale analog input range is ±VREF with a VDD / 2 (±0.8V) common-mode input range. VREF is the difference between VREFP and VREFN. See the Reference Configurations section for details. The MAX19710 includes a 3-wire serial interface to control operating modes and power management. The serial interface is SPI™ and MICROWIRE™ compatible. The MAX19710 serial interface selects shutdown, idle, standby, FD, transmit (Tx), and receive (Rx) modes, as well as controls aux-DAC and aux-ADC channels. The MAX19710 features two independent, high-speed, 10-bit buses for the Rx ADC and Tx DAC, which allow full-duplex (FD) operation for frequency-division duplex applications. Each bus can be disabled to optimize power management through the 3-wire interface. The Input Track-and-Hold (T/H) Circuits Figure 1 displays a simplified diagram of the Rx ADC input track-and-hold (T/H) circuitry. Both ADC inputs (IAP, QAP, IAN, and QAN) can be driven either differen- MICROWIRE is a trademark of National Semiconductor Corp. SPI is a trademark of Motorola, Inc. INTERNAL BIAS COM S5a S2a C1a S3a S4a IAP OUT C2a S4c S1 OUT IAN S4b C1b C2b S3b S5b S2b INTERNAL BIAS COM INTERNAL BIAS COM HOLD CLK HOLD TRACK TRACK INTERNAL NONOVERLAPPING CLOCK SIGNALS S5a S2a C1a S3a S4a QAP OUT C2a S4c S1 MAX19710 OUT QAN S4b C1b C2b S3b S2b INTERNAL BIAS S5b COM Figure 1. Rx ADC Internal T/H Circuits 16 ______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End DIFFERENTIAL INPUT VOLTAGE DIFFERENTIAL INPUT (LSB) OFFSET BINARY (AD0–AD9) VREF x 512/512 511 (+Full Scale - 1 LSB) 11 1111 1111 1023 VREF x 511/512 510 (+Full Scale - 2 LSB) 11 1111 1110 1022 VREF x 1/512 +1 10 0000 0001 513 VREF x 0/512 0 (Bipolar Zero) 10 0000 0000 512 -VREF x 1/512 -1 01 1111 1111 511 -VREF x 511/512 -511 (-Full Scale + 1 LSB) 00 0000 0001 1 -VREF x 512/512 -512 (-Full Scale) 00 0000 0000 0 1 LSB = 2 x VREF 1024 VREF VREF = VREFP - VREFN VREF VREF 11 1111 1111 11 1111 1110 11 1111 1101 10 0000 0001 10 0000 0000 01 1111 1111 (COM) VREF OFFSET BINARY OUTPUT CODE (LSB) OUTPUT DECIMAL CODE 00 0000 0011 00 0000 0010 00 0000 0001 00 0000 0000 -512 -511 -510 -509 -1 0+ 1 +509 +510 +511 +512 (COM) INPUT VOLTAGE (LSB) Figure 2. Rx ADC Transfer Function tially or single-ended. Match the impedance of IAP and IAN, as well as QAP and QAN, and set the input signal common-mode voltage within the VDD / 2 (±0.8V) Rx ADC range for optimum performance. Rx ADC System Timing Requirements Figure 3 shows the relationship between the clock, analog inputs, and the resulting output data. Channels IA and QA are sampled on the rising edge of the clock sig- nal (CLK) and the resulting data is multiplexed at the AD0–AD9 outputs. Channel IA data is updated on the rising edge and channel QA data is updated on the falling edge of CLK. Including the delay through the output latch, the total clock-cycle latency is 5 clock cycles for channel IA and 5.5 clock cycles for channel QA. Digital Output Data (AD0–AD9) AD0–AD9 are the Rx ADC digital logic outputs of the MAX19710. The logic level is set by OVDD from 1.8V to VDD. The digital output coding is offset binary (Table 1). Keep the capacitive load on the digital outputs AD0–AD9 as low as possible (< 15pF) to avoid large digital currents feeding back into the analog portion of the MAX19710 and degrading its dynamic performance. Buffers on the digital outputs isolate the outputs from heavy capacitive loads. Adding 100Ω resistors in series with the digital outputs close to the MAX19710 will help improve ADC performance. Refer to the MAX19710EVKIT schematic for an example of the digital outputs driving a digital buffer through 100Ω series resistors. During SHDN, IDLE, STBY, SPI2, and SPI4 states, digital outputs AD0–AD9 are tri-stated. Dual 10-Bit Tx DACs The dual 10-bit digital-to-analog converters (Tx DACs) operate with clock speeds up to 7.5MHz. The Tx DAC digital inputs, DA0–DA9, are multiplexed on a single 10-bit transmit bus. The voltage reference determines the Tx DAC full-scale voltage at IDP, IDN and QDP, QDN analog outputs. See the Reference Configurations section for setting the reference voltage. ______________________________________________________________________________________ 17 MAX19710 Table 1. Rx ADC Output Codes vs. Input Voltage MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End 5.5 CLOCK-CYCLE LATENCY (QA) 5 CLOCK-CYCLE LATENCY (IA) IA QA tCLK tCL tCH CLK tDOQ D0–D9 tDOI D0Q D1I D1Q D2I D2Q D3I D3Q D4I D4Q D5I D5Q D6I D6Q Figure 3. Rx ADC System Timing Diagram Table 2. Tx DAC Output Voltage vs. Input Codes (Internal Reference Mode VREFDAC = 1.024V, External Reference Mode VREFDAC = VREFIN, VFS = 400 for 800mVP-P Full Scale) DIFFERENTIAL OUTPUT VOLTAGE (V) OFFSET BINARY (DA0–DA9) INPUT DECIMAL CODE (VFS ) VREFDAC 1024 × 1023 1023 11 1111 1111 1023 (VFS ) VREFDAC 1024 × 1023 1023 11 1111 1110 1022 (VFS ) VREFDAC 1024 × 1023 1023 10 0000 0001 513 (VFS ) VREFDAC 1024 × 1023 1023 10 0000 0000 512 (VFS ) VREFDAC 1024 × 1023 1023 01 1111 1111 511 (VFS ) VREFDAC 1024 × 1023 1023 00 0000 0001 1 (VFS ) VREFDAC 1024 × 1023 1023 00 0000 0000 0 The Tx DAC outputs (IDN, IDP, QDN, QDP) are biased at an adjustable common-mode DC level and designed to drive a differential input stage with ≥ 70kΩ input impedance. This simplifies the analog interface between RF quadrature upconverters and the MAX19710. Many RF upconverters require a 0.89V to 1.36V common-mode bias. The MAX19710 common-mode DC bias eliminates discrete level-setting resistors and code-generated level shifting while preserving the full dynamic range of each Tx DAC. The Tx DAC differential analog outputs cannot be used in single-ended mode because of the 18 internally generated common-mode DC level. Table 2 shows the Tx DAC output voltage vs. input codes. Table 10 shows the selection of DC common-mode levels. See Figure 4 for an illustration of the Tx DAC analog output levels. The Tx DAC also features independent DC offset trim on each ID–QD channel. This feature is configured through the SPI interface. The DC offset correction is used to optimize sideband and carrier suppression in the Tx signal path (see Table 9). ______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End MAX19710 MAX19710 EXAMPLE: Tx DAC CH-ID Tx RFIC INPUT REQUIREMENTS • DC COMMON-MODE BIAS = 0.9V (MIN), 1.3V (TYP) 0° 90° • BASEBAND INPUT = ±400mV DC-COUPLED Tx DAC CH-QD FULL SCALE = 1.56V COMMON-MODE LEVEL VCOMD = 1.36V SELECT CM1 = 0, CM0 = 0 VCOMD = 1.36V VFS = ±400mV ZERO SCALE = 1.16V 0V Figure 4. Tx DAC Common-Mode DC Level at IDN, IDP or QDN, QDP Differential Outputs CLK tDHQ tDSQ D0–D9 Q: N - 2 I: N - 1 Q: N - 1 tDSI Q: N I: N I: N + 1 tDHI ID N-2 N-1 N QD N-2 N-1 N Figure 5. Tx DAC System Timing Diagram ______________________________________________________________________________________ 19 MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End Tx DAC Timing Figure 5 shows the relationship among the clock, input data, and analog outputs. Channel ID data is latched on the falling edge of the clock signal, and channel QD data is latched on the rising edge of the clock signal, at which point both ID and QD outputs are simultaneously updated. 3-Wire Serial Interface and Operation Modes The 3-wire serial interface controls the MAX19710 operation modes as well as the three 12-bit aux-DACs and the 10-bit aux-ADC. Upon power-up, program the MAX19710 to operate in the desired mode. Use the 3wire serial interface to program the device for shutdown, idle, standby, FD, Rx, Tx, aux-DAC controls, or aux-ADC conversion. A 16-bit data register sets the mode control as shown in Table 3. The 16-bit word is composed of four control bits (A3–A0) and 12 data bits (D11–D0). Data is shifted in MSB first (D11) and LSB last (A0) format. Table 4 shows the MAX19710 power-management modes. Table 5 shows the SPI-controlled Tx, Rx, and FD modes. The serial interface remains active in all modes. SPI Register Description Program the control bits, A3–A0, in the register as shown in Table 3 to select the operating mode. Modify A3–A0 bits to select from ENABLE-16, Aux-DAC1, Aux-DAC2, Aux-DAC3, IOFFSET, QOFFSET, COMSEL, Aux-ADC, ENABLE-8, and WAKEUP-SEL modes. ENABLE-16 is the default operating mode (see Table 6). This mode allows for shutdown, idle, and standby states as well as switching between FAST, SLOW, Rx and Tx modes. Tables 4 and 5 show the required SPI settings for each mode. In ENABLE-16 mode, the aux-DACs have independent control bits E4, E5, and E6, and bit E9 enables the auxADC. Table 7 shows the auxiliary DAC enable codes. Table 8 shows the auxiliary ADC enable code. Bits E11 and E10 are reserved. Program bits E11 and E10 to logic-low. Bits E3, E7, and E8 are not used. Modes aux-DAC1, aux-DAC2, and aux-DAC3 select the aux-DAC channels named DAC1, DAC2, and DAC3 and hold the data inputs for each DAC. Bits _D11–_D0 are the data inputs for each aux-DAC and can be programmed through SPI. The MAX19710 also includes two 6-bit registers that can be programmed to adjust the offsets for the Tx DAC ID and QD channels independently (see Table 9). Use the COMSEL mode to select the output common-mode voltage with bits CM1 and CM0 (see Table 10). Use the aux-ADC mode to start the auxiliary ADC conversion (see the 10-Bit, 333ksps 20 Auxiliary ADC section for details). Use ENABLE-8 mode for faster enable and switching between shutdown, idle, and standby states as well as switching between FAST, SLOW, Rx and Tx modes and the FD mode. The WAKEUP-SEL register selects the operating mode that the MAX19710 is to enter immediately after coming out of shutdown (Table 11). See the Wake-Up Function section for more information. Shutdown mode offers the most dramatic power savings by shutting down all the analog sections (including the reference) of the MAX19710. In shutdown mode, the Rx ADC digital outputs are in tri-state mode, the Tx DAC digital inputs are internally pulled to OVDD, and the Tx DAC outputs are at 0V. When the Rx ADC outputs transition from tri-state to active mode, the last converted word is placed on the digital output bus. The Tx DAC previously stored data is lost when coming out of shutdown mode. The wake-up time from shutdown mode is dominated by the time required to charge the capacitors at REFP, REFN, and COM. In internal reference mode and buffered external reference mode, the wake-up time is typically 500µs to enter Rx mode, 26.2µs to enter Tx mode, and 500µs to enter FD mode. In all operating modes the Tx DAC inputs DA0–DA9 are internally pulled to OVDD. To reduce the supply current of the MAX19710 in shutdown mode do not pull DA0–DA9 low. This consideration is especially important in shutdown mode to achieve the lowest quiescent current. In idle mode, the reference and clock distribution circuits are powered, but all other functions are off. The Rx ADC outputs AD0–AD9 are forced to tri-state. The Tx DAC DA0–DA9 inputs are internally pulled to OVDD, while the Tx DAC outputs are at 0V. The wake-up time is 7.3µs to enter Rx mode, 5.2µs to enter Tx mode, and 7.3µs to enter FD mode. When the Rx ADC outputs transition from tri-state to active, the last converted word is placed on the digital output bus. In standby mode, the reference is powered but all other device functions are off. The wake-up time from standby mode is 7.5µs to enter Rx mode, 22.2µs to enter Tx mode, and 22.2µs to enter FD mode. When the Rx ADC outputs transition from tri-state to active, the last converted word is placed on the digital output bus. FAST and SLOW Rx and Tx Modes The MAX19710 features FAST and SLOW modes for switching between Rx and Tx operation. In FAST Tx mode, the Rx ADC core is powered on but the ADC digital outputs AD0–AD9 are tri-stated. The Tx DAC digital bus is active and the DAC core is fully operational. ______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End D11 REGISTER NAME D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 A3 A2 A1 A0 (MSB) 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1 (LSB) ENABLE-16 E11 = 0 Reserved E10 = 0 Reserved E9 — — E6 E5 E4 — E2 E1 E0 0 0 0 0 Aux-DAC1 1D11 1D10 1D9 1D8 1D7 1D6 1D5 1D4 1D3 1D2 1D1 1D0 0 0 0 1 Aux-DAC2 2D11 2D10 2D9 2D8 2D7 2D6 2D5 2D4 2D3 2D2 2D1 2D0 0 0 1 0 Aux-DAC3 3D11 3D10 3D9 3D8 3D7 3D6 3D5 3D4 3D3 3D2 3D1 3D0 0 0 1 1 IO4 IO3 IO2 IO1 IOFFSET — — — — — — IO5 IO0 0 1 0 0 QOFFSET — — — — — — QO5 QO4 QO3 QO2 QO1 QO0 0 1 0 1 COMSEL — — — — — — — — — — CM1 CM0 0 1 1 0 Aux-ADC AD11 = 0 Reserved AD10 AD9 AD8 AD7 AD6 AD5 AD4 AD3 AD2 AD1 AD0 0 1 1 1 ENABLE-8 — — — — — — — — — E2 E1 E0 1 0 0 0 WAKEUP-SEL — — — — — — — — — W2 W1 W0 1 0 0 1 — = Not used. Table 4. Power-Management Modes ADDRESS DATA BITS MODE A3 A2 A1 A0 E9* 1 0000 (16-Bit Mode) or 1000 (8-Bit Mode) X** X** E2 0 0 0 E1 0 0 1 E0 0 1 0 SHDN FUNCTION (POWER MANAGEMENT) DESCRIPTION COMMENT SHUTDOWN Rx ADC = OFF Tx DAC = OFF (TX DAC outputs at 0V) Aux-DAC = OFF Aux-ADC = OFF CLK = OFF REF = OFF Device is in complete shutdown. IDLE Rx ADC = OFF Tx DAC = OFF (TX DAC outputs at 0V) Aux-DAC = Last State CLK = ON REF = ON Fast turn-on time. Moderate idle power. STANDBY Rx ADC = OFF Tx DAC = OFF (TX DAC outputs at 0V) Aux-DAC = Last State CLK = OFF REF = ON Slow turn-on time. Low standby power. IDLE STBY X = Don’t care. *Bit E9 is not available in 8-bit mode. **In IDLE and STBY modes, the aux-ADC can be turned on or off. ______________________________________________________________________________________ 21 MAX19710 Table 3. MAX19710 Mode Control MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End Table 5. MAX19710 Tx, Rx, and FD Control Using SPI Commands ADDRESS A3 A2 A1 DATA BITS A0 E2 0 1 0000 (16-Bit Mode) and 1000 (8-Bit Mode) 1 1 1 E1 1 0 0 1 1 E0 1 0 1 0 1 MODE FUNCTION (Tx-Rx SWITCHING SPEED) DESCRIPTION COMMENT SLOW Rx Mode: Rx ADC = ON Rx Bus = Enabled Tx DAC = OFF (Tx DAC outputs at 0V) Tx Bus = OFF (all inputs are pulled high) Slow transition to Tx mode from this mode. Low power. SLOW Tx Mode: Rx ADC = OFF Rx Bus = Tri-state Tx DAC = ON Tx Bus = ON Slow transition to Rx mode from this mode. Low power. FAST Rx Mode: Rx ADC = ON Rx Bus = Enabled Tx DAC = ON (Tx DAC outputs at midscale) Tx Bus = OFF (all inputs are pulled high) Fast transition to Tx mode from this mode. Moderate power. FAST Tx Mode: Rx ADC = ON Rx Bus = Tri-state Tx DAC = ON Tx Bus = ON Fast transition to Rx mode from this mode. Moderate power. FAST FD Mode: Rx ADC = ON Rx Bus = ON Tx DAC = ON Tx Bus = ON Default Mode Fast transition to any mode. Moderate power. SPI1-Rx SPI2-Tx SPI3-Rx SPI4-Tx FD In FAST Rx mode, the Tx DAC core is powered on. The Tx DAC outputs are set to midscale. In this mode, the Tx DAC input bus is disconnected from the DAC core and DA0–DA9 are internally pulled to OVDD. The Rx ADC digital bus is active and the ADC core is fully operational. In FAST mode, the switching time from Tx to Rx, or Rx to Tx is minimized because the converters are on and do not have to recover from a power-down state. In FAST mode, the switching time from Rx to Tx and Tx to Rx is 0.1µs. Power consumption is higher in FAST mode because both Tx and Rx cores are always on. 22 In SLOW Tx mode, the Rx ADC core is powered off and the ADC digital outputs AD0–AD9 are tri-stated. The Tx DAC digital bus is active and the DAC core is fully operational. In SLOW Rx mode, the Tx DAC core is powered off. The Tx DAC outputs are set to 0. In SLOW Rx mode, the Tx DAC input bus is disconnected from the DAC core and DA0–DA9 are internally pulled to OVDD. The Rx ADC digital bus is active and the ADC core is fully operational. The switching times for SLOW modes are 5.2µs for Rx to Tx and 7.3µs for Tx to Rx. ______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End REGISTER NAME D11 D10 D9 D8 D7 D6 D5 D4 D3 D2 D1 D0 16 (MSB) 15 14 13 12 11 10 9 8 7 6 5 0 0 1 1 1 0 0 Aux-ADC = ON — — 0 1 1 0 1 0 0 0 0 0 0 0 0 0 0 0 ENABLE-16 Aux-DAC1 0 — Aux-DAC1 to Aux-DAC3 = ON 0 0 FD mode 0 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 DAC1 output set to 1.1V Aux-DAC2 0 0 DAC2 output set to 0V Aux-DAC3 0 0 DAC3 output set to 0V 0 0 IOFFSET — — — — — — QOFFSET — — — — — — COMSEL — — — — — — — — — — 0 0 0 0 0 0 0 0 0 Aux-ADC 0 ENABLE-8 — WAKEUP-SEL E5 E4 0 0 0 0 No offset on channel QD VCOMD = 1.36V 0 0 1 1 Aux-ADC = ON, Conversion = IDLE, Aux-ADC REF = 2.048V, MUX = ADC1, Averaging = 1, Clock Divider = 1, DOUT = Disabled — — — — — — — — — Aux-DAC3 Aux-DAC2 — — — — — — — 1 FD mode 1 1 1 Wake-up state = FD mode Aux-DAC1 E9 SELECTION Aux-ADC is Powered ON Aux-ADC is Powered OFF 0 0 0 ON ON ON 0 (Default) 0 0 1 ON ON OFF 1 0 1 0 ON OFF ON 0 1 1 ON OFF OFF 1 0 0 OFF ON ON 1 0 1 OFF ON OFF 1 1 0 OFF OFF ON 1 1 1 OFF OFF OFF 0 0 0 Default mode — Table 8. Aux-ADC Enable Table (ENABLE-16 Mode) Table 7. Aux-DAC Enable Table (ENABLE-16 Mode) E6 No offset on channel ID Power consumption in SLOW Tx mode is 21.9mW, and 21.3mW in SLOW Rx mode. Power consumption in FAST Tx mode is 29.1mW, and 28.5mW in FAST Rx mode. FD Mode The MAX19710 features an FD mode, which is ideal for applications supporting frequency-division duplex. In FD mode, both Rx ADC and Tx DAC, as well as their ______________________________________________________________________________________ 23 MAX19710 Table 6. MAX19710 Default (Power-On) Register Settings MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End Table 9. Offset Control Bits for ID and QD Channels (IOFFSET or QOFFSET Mode) BITS IO5–IO0 WHEN IN IOFFSET MODE, BITS QO5–QO0 WHEN IN QOFFSET MODE IO5/QO5 IO4/QO4 IO3/QO3 IO2/QO2 IO1/QO1 IO0/QO0 OFFSET 1 LSB = (VFSP-P / 1023) 1 1 1 1 1 1 -31 LSB 1 1 1 1 1 0 -30 LSB 1 1 1 1 0 1 -29 LSB • • • • • • • • • • • • • • • • • • • • • 1 0 0 0 1 0 -2 LSB 1 0 0 0 0 1 -1 LSB 1 0 0 0 0 0 0mV 0 0 0 0 0 0 0mV (Default) 0 0 0 0 0 1 1 LSB 0 0 0 0 1 0 2 LSB • • • • • • • • • • • • • • • • • • • • • 0 1 1 1 0 1 29 LSB 0 1 1 1 1 0 30 LSB 0 1 1 1 1 1 31 LSB Note: 1 LSB = (800mVP-P / 1023) = 0.782mV. Table 10. Common-Mode Select (COMSEL Mode) CM1 CM0 Tx PATH OUTPUT COMMON MODE (V) 0 0 1.36 (Default) 0 1 1.20 1 0 1.05 1 1 0.89 respective digital buses, are active and the device can receive and transmit simultaneously. Switching from FD mode to other Rx or Tx modes is fast (0.1µs) since the on-board converters are already powered. Consequently, power consumption in this mode is the maximum of all operating modes. In FD mode the MAX19710 consumes 30mW. Wake-Up Function The MAX19710 uses the SPI interface to control the operating modes of the device including the shutdown and wake-up functions. Once the device has been placed in shutdown through the appropriate SPI command, the first pulse on CS/WAKE performs a wake-up 24 Table 11. WAKEUP-SEL Register W2 W1 W0 POWER MODE AFTER WAKE-UP (WAKE-UP STATE) 0 0 0 Invalid Value. This value is ignored when inadvertently written to the WAKEUP-SEL register. 0 0 1 IDLE 0 1 0 STBY 0 1 1 SPI1-SLOW Rx 1 0 0 SPI2-SLOW Tx 1 0 1 SPI3-FAST Rx 1 1 0 SPI4-FAST Tx 1 1 1 FD (Default) function. At the first rising edge of CS/WAKE, the MAX19710 is forced to a preset operating mode determined by the WAKEUP-SEL register. This mode is termed the wake-up state. If the WAKEUP-SEL register has not been programmed, the wake-up state for the MAX19710 is FD mode by default (Tables 6, 11). The WAKEUP-SEL register cannot be programmed with W2 ______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End MAX19710 tCSW CS/WAKE tCSS tCP tCS SCLK tCH tDS DIN tCL tDH MSB LSB Figure 6. Serial-Interface Timing Diagram CS/WAKE SCLK DIN 16-BIT SERIAL DATA INPUT ADC DIGITAL OUTPUT SINAD SETTLES TO WITHIN 1dB AD0–AD9 tWAKE,SD,ST_ TO Rx MODE OR tENABLE,RX DAC ANALOG OUTPUT SETTLES TO 10 LSB ERROR ID/QD tWAKE,SD,ST_ TO Tx MODE OR tENABLE,TX Figure 7. Mode-Recovery Timing Diagram = 0, W1 = 0, and W0 = 0. If this value is inadvertently written to the device, it is ignored and the register continues to store its previous value. Upon wake-up, the MAX19710 enters the power mode determined by the WAKEUP-SEL register, however, all other settings (Tx DAC offset, Tx DAC common-mode voltage, aux-DAC settings, aux-ADC state) are restored to their values prior to shutdown. serial clock (SCLK). After 16 bits are loaded into the serial input register, data is transferred to the latch when CS/WAKE transitions high. CS/WAKE must transition high for a minimum of 80ns before the next write sequence. SCLK can idle either high or low between transitions. Figure 6 shows the detailed timing diagram of the 3-wire serial interface. The only SPI line that is monitored by the MAX19710 during shutdown is CS/WAKE. Any information transmitted to the MAX19710 concurrent with the CS/WAKE wake-up pulse is ignored. Figure 7 shows the mode-recovery timing diagram. tWAKE is the wake-up time when exiting shutdown, idle, or standby mode and entering Rx, Tx, or FD mode. tENABLE is the recovery time when switching between either Rx or Tx mode. tWAKE or tENABLE is the time for the Rx ADC to settle within 1dB of specified SINAD performance and Tx DAC settling to 10 LSB error. tWAKE and tENABLE times are measured after the 16-bit serial command is latched into the MAX19710 by a CS/WAKE transition high. In FAST mode, the recovery time is 0.1µs to switch between Tx or Rx modes. SPI Timing The serial digital interface is a standard 3-wire connection CS/WAKE, SCLK, DIN) compatible with SPI/QSPI™/ MICROWIRE/DSP interfaces. Set CS/WAKE low to enable the serial data loading at DIN or output at DOUT. Following a CS/WAKE high-to-low transition, data is shifted synchronously, most significant bit first, on the rising edge of the Mode-Recovery Timing QSPI is a trademark of Motorola, Inc. ______________________________________________________________________________________ 25 MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End System Clock Input (CLK) Both the Rx ADC and Tx DAC share the CLK input. The CLK input accepts a CMOS-compatible signal level set by OVDD from 1.8V to VDD. Since the interstage conversion of the device depends on the repeatability of the rising and falling edges of the external clock, use a clock with low jitter and fast rise and fall times (< 2ns). Specifically, sampling occurs on the rising edge of the clock signal, requiring this edge to provide the lowest possible jitter. Any significant clock jitter limits the SNR performance of the on-chip Rx ADC as follows: ⎛ ⎞ 1 SNR = 20 × log ⎜ ⎟ ⎝ 2 × π × fIN × t AJ ⎠ where fIN represents the analog input frequency and tAJ is the time of the clock jitter. Clock jitter is especially critical for undersampling applications. Consider the clock input as an analog input and route away from any analog input or other digital signal lines. The MAX19710 clock input operates with an OVDD / 2 voltage threshold and accepts a 50% ±10% duty cycle. When the clock signal is stopped at CLK input (CLK = 0V or OVDD), all internal registers hold their last value and the MAX19710 saves the last power-management mode or Tx/Rx/FD command. All converter circuits (Rx ADC, Tx DAC, aux-ADC, and aux-DACs) hold their last value. When the clock signal is restarted at CLK, allow 7.5µs (clock wake-up time) for the internal clock circuitry to settle before updating the Tx DAC, reading a valid Rx ADC conversion result, or starting an aux-ADC conversion. This ensures the converters (Rx ADC, Tx DAC, aux-ADC) meet all dynamic performance specifications. The aux-DAC channels are not dependent on CLK, so they may be updated when CLK is idle. 12-Bit, Auxiliary Control DACs The MAX19710 includes three 12-bit aux-DACs (DAC1, DAC2, DAC3) with 1µs settling time for controlling variable-gain amplifier (VGA), automatic gain-control (AGC), and automatic frequency-control (AFC) functions. The aux-DAC output range is 0.2V to 2.57V as defined by VOH - VOL. During power-up, the VGA and AGC outputs (DAC2 and DAC3) are at zero. The AFC DAC (DAC1) is at 1.1V during power-up. The aux-DACs can be independently controlled through the SPI bus, except during SHDN mode where the aux-DACs are turned off completely and the output voltage is set to zero. In STBY and IDLE modes the aux-DACs maintain the last value. On wake-up from SHDN, the aux-DACs resume the last values. 26 Loading on the aux-DAC outputs should be carefully observed to achieve the specified settling time and stability. The capacitive load must be kept to a maximum of 5pF including package and trace capacitance. The resistive load must be greater than 200kΩ. If capacitive loading exceeds 5pF, then add a 10kΩ resistor in series with the output. Adding the series resistor helps drive larger load capacitance (< 15pF) at the expense of slower settling time. 10-Bit, 333ksps Auxiliary ADC The MAX19710 integrates a 333ksps, 10-bit aux-ADC with an input 4:1 multiplexer. In the aux-ADC mode register, setting bit AD0 begins a conversion with the auxiliary ADC. Bit AD0 automatically clears when the conversion is complete. Setting or clearing AD0 during a conversion has no effect (see Table 12). Bit AD1 determines the internal reference of the auxiliary ADC (see Table 13). Bits AD2 and AD3 determine the auxiliary ADC input source (see Table 14). Bits AD4, AD5, and AD6 select the number of averages taken when a single start-convert command is given. The conversion time increases as the number of averages increases (see Table 15). The conversion clock can be divided down from the system clock by properly setting bits AD7, AD8, and AD9 (see Table 16). The aux-ADC output data can be written out of DOUT by setting bit AD10 high (see Table 17). The aux-ADC features a 4:1 input multiplexer to allow measurements on four input sources. The input sources are selected by AD3 and AD2 (see Table 14). Two of the multiplexer inputs (ADC1 and ADC2) can be connected to external sources such as an RF power detector like the MAX2208 or temperature sensor like the MAX6613. The other two multiplexer inputs are internal connections to VDD and OVDD that monitor the powersupply voltages. The internal VDD and OVDD connections are made through integrated dividers that yield VDD / 2 and OVDD / 2 measurement results. The auxADC voltage reference can be selected between an internal 2.048V bandgap reference or VDD (see Table 13). The VDD reference selection is provided to allow measurement of an external voltage source with a fullscale range extending beyond the 2.048V level. The input source voltage range cannot extend above VDD. The conversion requires 12 clock edges (1 for input sampling, 1 for each of the 10 bits, and 1 at the end for loading into the serial output register) to complete one conversion cycle (when no averaging is being done). Each conversion of an average (when averaging is set greater than 1) requires 12 clock edges. The conversion clock is generated from the system clock input (CLK). An SPI-programmable divider divides the system ______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End AD0 SELECTION Table 16. Auxiliary ADC Clock (CLK) Divider 0 Aux-ADC Idle (Default) AD9 AD8 AD7 Aux-ADC CONVERSION CLOCK 1 Aux-ADC Start-Convert 0 0 0 CLK Divided by 1 (Default) 0 0 1 CLK Divided by 2 0 1 0 CLK Divided by 4 0 1 1 CLK Divided by 8 1 0 0 CLK Divided by 16 1 0 1 CLK Divided by 32 1 1 0 CLK Divided by 64 1 1 1 CLK Divided by 128 Table 13. Auxiliary ADC Reference AD1 SELECTION 0 Internal 2.048V Reference (Default) 1 Internal VDD Reference Table 14. Auxiliary ADC Input Source Table 17. Auxiliary ADC Data Output Mode AD3 AD2 Aux-ADC INPUT SOURCE 0 0 ADC1 (Default) 0 1 ADC2 AD10 SELECTION 1 0 VDD / 2 0 Aux-ADC Data is Not Available on DOUT (Default) 1 1 OVDD / 2 1 Aux-ADC Enters Data Output Mode Where Data is Available on DOUT Table 15. Auxiliary ADC Averaging AD6 AD5 AD4 Aux-ADC AVERAGING 0 0 0 1 Conversion (No Averaging) (Default) 0 0 1 Average of 2 Conversions 0 1 0 Average of 4 Conversions 0 1 1 Average of 8 Conversions 1 0 0 Average of 16 Conversions 1 0 1 Average of 32 Conversions 1 1 X Average of 32 Conversions X = Don’t care. clock by the appropriate divisor (set with bits AD7, AD8, and AD9; see Table 16) and provides the conversion clock to the auxiliary ADC. The auxiliary ADC has a maximum conversion rate of 333ksps. The maximum conversion clock frequency is 4MHz (333ksps x 12 clocks). Choose the proper divider value to keep the conversion clock frequency under 4MHz, based upon the system CLK frequency supplied to the MAX19710 (see Table 16). The total conversion time (tCONV) of the auxiliary ADC can be calculated as t CONV = (12 x N AVG x N DIV) / f CLK; where N AVG is the number of averages (see Table 15), NDIV is the CLK divisor (see Table 16), and fCLK is the system CLK frequency. Reading DOUT from the Aux-ADC DOUT is normally in a high-impedance condition. Upon setting the auxiliary ADC start conversion bit (bit AD0), DOUT becomes active and goes high, indicating that the aux-ADC is busy. When the conversion cycle is complete (including averaging), the data is placed into an output register and DOUT goes low, indicating that the output data is ready to be driven onto DOUT. When bit AD10 is set (AD10 = 1), the aux-ADC enters a data output mode where data is available at DOUT on the next low assertion of CS/WAKE. The auxiliary ADC data is shifted out of DOUT (MSB first) with the data transitioning on the falling edge of the serial clock (SCLK). Since a DOUT read requires 16 bits, DOUT holds the value of the last conversion data bit for the last 6 bits (6 least significant bits) following the aux-ADC conversion data. DOUT enters a high-impedance state when CS/WAKE is deasserted high. When bit AD10 is cleared (AD10 = 0), the aux-ADC data is not available on DOUT (see Table 17). After the aux-ADC completes a conversion, the data result is loaded to an output register waiting to be shifted out. No further conversions are possible until data is shifted out. This means that if the first conversion command sets AD10 = 0, AD0 = 1, then it cannot be followed by conversion commands setting AD10 = 0, AD0 = 1 or AD10 = 1, AD0 = 1. If this sequence of commands is inadvertently used then DOUT is disabled. To resume normal operation set AD0 = 0. ______________________________________________________________________________________ 27 MAX19710 Table 12. Auxiliary ADC Convert MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End The fastest method to perform sequential conversions with the aux-ADC is by sending consecutive commands setting AD10 = 1, AD0 = 1. With this sequence the CS/WAKE falling edge shifts data from the previous conversion on to DOUT and the rising edge of CS/WAKE loads the next conversion command at DIN. Allow enough time for each conversion to complete before sending the next conversion command. See Figure 8 for single and continuous conversion examples. 1. SINGLE AUX-ADC CONVERSION WITH CONVERSION DATA READOUT AT A LATER TIME tCSD CS/WAKE SCLK 1 DIN 0 tCD 16 0 1 0 1 1 1 16 1 1 0 16 1 0 0 1 1 tCHZ 1 10 1 D9 AUX-ADC REGISTER ADDRESS DOUT TRANSITIONS FROM HIGH IMPEDANCE TO LOGICHIGH INDICATING START OF CONVERSION D0 D0 HELD CONVERSION RESULT DATA BIT D0 IS HELD FOR THE SIX LEAST SIGNIFICANT BITS FIRST FALLING EDGE OF CS/WAKE AFTER DOUT IS ENABLED STARTS SHIFTING THE AUX-ADC CONVERSION DATA ON THE FALLING EDGE OF SCLK AD10 = 1, AD0 = 0, AUX-ADC IDLE (NO CONVERSION), DOUT ENABLED AND CONVERSION DATA IS SHIFTED OUT ON NEXT CS/WAKE FALLING EDGE DOUT TRANSITIONS LOW INDICATING END OF CONVERSION, DATA IS AVAILABLE AND CAN BE SHIFTED OUT IF DOUT IS ENABLED, AD0 CLEARED D1 AUX-ADC REGISTER ADDRESS IF AUX-ADC CONVERSION DOES NOT NEED TO BE READ IMMEDIATELY, THE SPI INTERFACE IS FREE AND CAN BE USED FOR OTHER FUNCTIONS, SUCH AS HOUSEKEEPING AUX-DAC ADJUSTMENT, ETC. 16 DIN SET HIGH DURING SINGLE READ DOUT AD10 = 0, AD0 = 1, PERFORM CONVERSION, DOUT DISABLED 11 DOUT TRANSITIONS TO HIGH IMPEDANCE 10-BIT AUX-ADC CONVERSION RESULT IS SHIFTED OUT ON DOUT ON THE FALLING EDGE OF SCLK MSB FIRST 2. CONTINUOUS AUX-ADC CONVERSIONS tCONV CS/WAKE tDCS SCLK 1 DIN 0 0 1 0 1 1 16 1 1 0 10 D9 DOUT 11 1 D1 12 13 14 15 16 1 1 0 1 1 1 0 D0 D0 HELD 10 11 1 D9 D1 12 13 14 15 16 1 0 1 1 1 D0 AD10 = 1, AD0 = 1, PERFORM CONVERSION, DOUT ENABLED AD10 = 1, AD0 = 1, PERFORM CONVERSION, DOUT ENABLED AD10 = 1, AD0 = 1, PERFORM CONVERSION, DOUT ENABLED AUX-ADC REGISTER ADDRESS FIRST 10-BIT AUX-ADC CONVERSION RESULT IS SHIFTED OUT ON DOUT ON THE FALLING EDGE OF SCLK MSB FIRST SECOND 10-BIT AUX-ADC CONVERSION RESULT IS SHIFTED OUT ON DOUT ON THE FALLING EDGE OF SCLK MSB FIRST DOUT TRANSITIONS HIGH INDICATING START OF SECOND CONVERSION DOUT TRANSITIONS HIGH INDICATING START OF THIRD CONVERSION DOUT TRANSITIONS LOW INDICATING END OF SECOND CONVERSION, DATA IS AVAILABLE AND CAN BE SHIFTED OUT IF DOUT IS ENABLED, AD0 CLEARED DOUT TRANSITIONS LOW INDICATING END OF THIRD CONVERSION, DATA IS AVAILABLE AND CAN BE SHIFTED OUT IF DOUT IS ENABLED, AD0 CLEARED DOUT TRANSITIONS FROM HIGH IMPEDANCE TO LOGICHIGH INDICATING START OF FIRST CONVERSION DOUT TRANSITIONS LOW INDICATING END OF FIRST CONVERSION, DATA IS AVAILABLE AND CAN BE SHIFTED OUT IF DOUT IS ENABLED, AD0 CLEARED D0 HELD Figure 8. Aux-ADC Conversions Timing 28 ______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End 25Ω IAP 0.1μF 22pF VIN COM 0.33μF 0.1μF IAN 25Ω 22pF MAX19710 25Ω QAP 0.1μF 22pF VIN Reference Configurations The MAX19710 features an internal precision 1.024Vbandgap reference that is stable over the entire powersupply and temperature ranges. The REFIN input provides two modes of reference operation. The voltage at REFIN (VREFIN) sets the reference operation mode (Table 18). In internal reference mode, connect REFIN to V DD . VREF is an internally generated 0.512V ±4% reference level. COM, REFP, and REFN are low-impedance outputs with VCOM = VDD / 2, VREFP = VDD / 2 + VREF / 2, and VREFN = VDD / 2 - VREF / 2. Bypass REFP, REFN, and COM each with a 0.33µF capacitor. Bypass REFIN to GND with a 0.1µF capacitor. In buffered external reference mode, apply 1.024V ±10% at REFIN. In this mode, COM, REFP, and REFN are low-impedance outputs with V COM = V DD / 2, VREFP = VDD / 2 + VREFIN / 4, and VREFN = VDD / 2 VREFIN / 4. Bypass REFP, REFN, and COM each with a 0.33µF capacitor. Bypass REFIN to GND with a 0.1µF capacitor. In this mode, the Tx path full-scale output is proportional to the external reference. For example, if the VREFIN is increased by 10% (max), the Tx path fullscale output is also increased by 10% or ±440mV. Applications Information Using Balun Transformer AC-Coupling 0.33μF 0.1μF QAN 25Ω 22pF Figure 9. Balun Transformer-Coupled Single-Ended-toDifferential Input Drive for Rx ADC An RF transformer (Figure 9) provides an excellent solution to convert a single-ended signal source to a fully differential signal for optimum ADC performance. Connecting the center tap of the transformer to COM provides a VDD / 2 DC level shift to the input. A 1:1 transformer can be used, or a step-up transformer can be selected to reduce the drive requirements. In general, the MAX19710 provides better SFDR and THD with fully differential input signals than single-ended signals, especially for high input frequencies. In differential mode, even-order harmonics are lower as both inputs (IAP, IAN, QAP, QAN) are balanced, and each of the Table 18. Reference Modes VREFIN REFERENCE MODE > 0.8V x VDD Internal Reference Mode. VREF is internally generated to be 0.512V. Bypass REFP, REFN, and COM each with a 0.33µF capacitor. 1.024V ±10% Buffered External Reference Mode. An external 1.024V ±10% reference voltage is applied to REFIN. VREF is internally generated to be VREFIN / 2. Bypass REFP, REFN, and COM each with a 0.33µF capacitor. Bypass REFIN to GND with a 0.1µF capacitor. ______________________________________________________________________________________ 29 MAX19710 DIN can be written independent of DOUT state. A 16-bit instruction at DIN updates the device configuration. To prevent modifying internal registers while reading data from DOUT, hold DIN at a high state (only applies if sequential aux-ADC conversions are not executed). This effectively writes all ones into address 1111. Since address 1111 does not exist, no internal registers are affected. MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End Rx ADC inputs only requires half the signal swing compared to single-ended mode. Figure 10 shows an RF transformer converting the MAX19710 Tx DAC differential analog outputs to single-ended. IDP VOUT Using Op-Amp Coupling Drive the MAX19710 Rx ADC with op amps when a balun transformer is not available. Figures 11 and 12 show the Rx ADC being driven by op amps for AC-coupled single-ended and DC-coupled differential applications. Amplifiers such as the MAX4454 and MAX4354 provide high speed, high bandwidth, low noise, and low distortion to maintain the input signal integrity. The op-amp circuit shown in Figure 12 can also be used to interface with the Tx DAC differential analog outputs to provide gain or buffering. The Tx DAC differential analog outputs cannot be used in single-ended mode because of the internally generated common-mode level. Also, the Tx DAC analog outputs are designed to drive a differential input stage with input impedance ≥ 70kΩ. If single-ended outputs are desired, use an amplifier to provide differential-to-single-ended conversion and select an amplifier with proper input commonmode voltage range. FDD Application MAX19710 IDN QDP QDN Figure 10. Balun Transformer-Coupled Differential-to-SingleEnded Output Drive for Tx DAC REFP High-Performance, Low-Power Analog Functions • Low-Risk, Proven Analog Front-End Solution • No Mixed-Signal Test Times • No NRE Charges • No IP Royalty Charges • Enables Digital Baseband and Scale with 65nm to 90nm CMOS 1kΩ VIN 0.1μF 100Ω 30 CIN 22pF 1kΩ COM REFN 0.1μF RISO 50Ω IAN 100Ω CIN 22pF REFP VIN 0.1μF 1kΩ MAX19710 RISO 50Ω QAP 100Ω Grounding, Bypassing, and Board Layout The MAX19710 requires high-speed board layout design techniques. Refer to the MAX19710 EV kit data sheet for a board layout reference. Place all bypass capacitors as close to the device as possible, preferably on the same side of the board as the device, using surface-mount devices for minimum inductance. Bypass VDD to GND with a 0.1µF ceramic capacitor in parallel with a 2.2µF RISO 50Ω IAP Figure 13 illustrates a typical FDD application circuit. The MAX19710 interfaces directly with a ZIF radio front-end to provide a complete “RF-to-Bits” solution for FDD applications such as private mobile radio (PMR), broadband access radio, and proprietary radio systems. The MAX19710 provides several system benefits to digital baseband developers: • Fast Time-to-Market • VOUT 1kΩ REFN CIN 22pF 0.1μF RISO 50Ω 100Ω QAN CIN 22pF Figure 11. Single-Ended Drive for Rx ADC ______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End MAX19710 R4 600Ω R5 600Ω RISO 22Ω R1 600Ω IAN CIN 5pF MAX19710 R2 600Ω R3 600Ω R6 600Ω R7 600Ω R8 600Ω R9 600Ω COM RISO 22Ω CIN 5pF R10 600Ω IAP R11 600Ω Figure 12. Rx ADC DC-Coupled Differential Drive capacitor. Bypass OVDD to OGND with a 0.1µF ceramic capacitor in parallel with a 2.2µF capacitor. Bypass REFP, REFN, and COM each to GND with a 0.33µF ceramic capacitor. Bypass REFIN to GND with a 0.1µF capacitor. Multilayer boards with separated ground and power planes yield the highest level of signal integrity. Use a split ground plane arranged to match the physical location of the analog ground (GND) and the digital outputdriver ground (OGND) on the device package. Connect the MAX19710 exposed backside paddle to the GND plane. Join the two ground planes at a single point so the noisy digital ground currents do not interfere with the analog ground plane. The ideal location for this connection can be determined experimentally at a point along the gap between the two ground planes. Make this connection with a low-value, surface-mount resistor (1Ω to 5Ω), a ferrite bead, or a direct short. Alternatively, all ground pins could share the same ground plane, if the ground plane is sufficiently isolated from any noisy digital system’s ground plane (e.g., downstream output buffer or DSP ground plane). Route high-speed digital signal traces away from sensitive analog traces. Make sure to isolate the analog input lines to each respective converter to minimize channel-to-channel crosstalk. Keep all signal lines short and free of 90° turns. Dynamic Parameter Definitions ADC and DAC Static Parameter Definitions Integral Nonlinearity (INL) Integral nonlinearity is the deviation of the values on an actual transfer function from a straight line. This straight line can be either a best-straight-line fit or a line drawn between the end points of the transfer function, once offset and gain errors have been nullified. The static linearity parameters for the device are measured using the best-straight-line fit (DAC Figure 14a). ______________________________________________________________________________________ 31 MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End VDD = 2.7V TO 3.3V OVDD = 1.8V TO VDD DATA MUX AD0 AD1 AD2 AD3 AD4 AD5 AD6 AD7 AD8 AD9 DATA MUX DA0 DA1 DA2 DA3 DA4 DA5 DA6 DA7 DA8 DA9 IAP 10-BIT ADC IAN QAP 10-BIT ADC FDD ZIF TRANSCEIVER QAN IDP 10-BIT DAC IDN QDP AGC 10-BIT DAC QDN SYSTEM CLOCK DAC1 PROGRAMMABLE OFFSET/CM 12-BIT AUX-DAC TCXO DAC2 SERIAL INTERFACE AND SYSTEM CONTROL 12-BIT AUX-DAC DAC3 CLK CS/WAKE SCLK DIN DOUT 1.024V REFERENCE BUFFER 12-BIT AUX-DAC REFIN REFP COM REFN ADC1 BATTERY VOLTAGE MONITOR TEMPERATURE MEASUREMENT 10-BIT AUX-ADC ADC2 MAX19710 VDD / 2 OVDD / 2 GND OGND Figure 13. Typical FDD Application Circuit 32 ______________________________________________________________________________________ DIGITAL BASEBAND ASIC 10-Bit, 7.5Msps, Full-Duplex Analog Front-End DAC Offset Error Offset error (Figure 14a) is the difference between the ideal and actual offset point. The offset point is the output value when the digital input is midscale. This error affects all codes by the same amount and usually can be compensated by trimming. ADC Gain Error Ideally, the ADC full-scale transition occurs at 1.5 LSB below full scale. The gain error is the amount of deviation between the measured transition point and the ideal transition point with the offset error removed. ADC Dynamic Parameter Definitions Aperture Jitter Figure 15 shows the aperture jitter (tAJ), which is the sample-to-sample variation in the aperture delay. Aperture Delay Aperture delay (tAD) is the time defined between the rising edge of the sampling clock and the instant when an actual sample is taken (Figure 15). Signal-to-Noise Ratio (SNR) For a waveform perfectly reconstructed from digital samples, the theoretical maximum SNR is the ratio of the full-scale analog input (RMS value) to the RMS quantization error (residual error) and results directly from the ADC’s resolution (N bits): 7 ANALOG OUTPUT VALUE 6 5 4 AT STEP 011 (0.5 LSB) 3 2 AT STEP 001 (0.25 LSB) 1 0 000 001 010 011 100 101 110 111 DIGITAL INPUT CODE Figure 14a. Integral Nonlinearity 6 ANALOG OUTPUT VALUE ADC Offset Error Ideally, the midscale transition occurs at 0.5 LSB above midscale. The offset error is the amount of deviation between the measured transition point and the ideal transition point. MAX19710 Differential Nonlinearity (DNL) Differential nonlinearity is the difference between an actual step width and the ideal value of 1 LSB. A DNL error specification of less than 1 LSB guarantees no missing codes (ADC) and a monotonic transfer function (ADC and DAC) (DAC Figure 14b). 1 LSB 5 DIFFERENTIAL LINEARITY ERROR (-0.25 LSB) 4 3 1 LSB 2 DIFFERENTIAL LINEARITY ERROR (+0.25 LSB) 1 0 000 001 010 011 100 101 DIGITAL INPUT CODE Figure 14b. Differential Nonlinearity CLK SNR(max) = 6.02 x N + 1.76 (in dB) In reality, there are other noise sources besides quantization noise: thermal noise, reference noise, clock jitter, etc. SNR is computed by taking the ratio of the RMS signal to the RMS noise. RMS noise includes all spectral components to the Nyquist frequency excluding the fundamental, the first five harmonics, and the DC offset. Signal-to-Noise and Distortion (SINAD) SINAD is computed by taking the ratio of the RMS signal to the RMS noise. RMS noise includes all spectral ANALOG INPUT tAD tAJ SAMPLED DATA (T/H) T/H TRACK HOLD TRACK Figure 15. T/H Aperture Timing ______________________________________________________________________________________ 33 MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End components to the Nyquist frequency excluding the fundamental and the DC offset. Effective Number of Bits (ENOB) ENOB specifies the dynamic performance of an ADC at a specific input frequency and sampling rate. An ideal ADC’s error consists of quantization noise only. ENOB for a full-scale sinusoidal input waveform is computed from: ENOB = (SINAD - 1.76) / 6.02 Total Harmonic Distortion (THD) THD is typically the ratio of the RMS sum of the first five harmonics of the input signal to the fundamental itself. This is expressed as: ⎡ (V22 + V32 + V42 + V52 + V62 THD = 20 x log ⎢ V1 ⎢⎣ )⎤ ⎥ ⎥⎦ where V1 is the fundamental amplitude and V2–V6 are the amplitudes of the 2nd- through 6th-order harmonics. Third Harmonic Distortion (HD3) HD3 is defined as the ratio of the RMS value of the third harmonic component to the fundamental input signal. Spurious-Free Dynamic Range (SFDR) SFDR is the ratio expressed in decibels of the RMS amplitude of the fundamental (maximum signal component) to the RMS value of the next-largest spurious component, excluding DC offset. Intermodulation Distortion (IMD) IMD is the total power of the intermodulation products relative to the total input power when two tones, fIN1 and fIN2, are present at the inputs. The intermodulation products are (fIN1 ± fIN2), (2 ✕ fIN1), (2 ✕ fIN2), (2 ✕ fIN1 ± fIN2), (2 ✕ fIN2 ± fIN1). The individual input tone levels are at -7dBFS. Power-Supply Rejection Power-supply rejection is defined as the shift in offset and gain error when the power supply is changed ±5%. Small-Signal Bandwidth A small -20dBFS analog input signal is applied to an ADC in such a way that the signal’s slew rate does not limit the ADC’s performance. The input frequency is then swept up to the point where the amplitude of the digitized conversion result has decreased by 3dB. Note that the T/H performance is usually the limiting factor for the small-signal input bandwidth. Full-Power Bandwidth A large -0.5dBFS analog input signal is applied to an ADC, and the input frequency is swept up to the point where the amplitude of the digitized conversion result has decreased by 3dB. This point is defined as the fullpower bandwidth frequency. DAC Dynamic Parameter Definitions Total Harmonic Distortion THD is the ratio of the RMS sum of the output harmonics up to the Nyquist frequency divided by the fundamental: ⎡ (V22 + V32 + ...+ Vn2 ) THD = 20 x log ⎢ V1 ⎢ ⎣ ⎤ ⎥ ⎥ ⎦ where V1 is the fundamental amplitude and V2 through Vn are the amplitudes of the 2nd through nth harmonic up to the Nyquist frequency. Spurious-Free Dynamic Range Spurious-free dynamic range (SFDR) is the ratio of RMS amplitude of the fundamental (maximum signal component) to the RMS value of the next-largest distortion component up to the Nyquist frequency excluding DC. 3rd-Order Intermodulation (IM3) IM3 is the power of the worst 3rd-order intermodulation product relative to the input power of either input tone when two tones, fIN1 and fIN2, are present at the inputs. The 3rd-order intermodulation products are (2 x fIN1 ± fIN2), (2 ✕ fIN2 ± fIN1). The individual input tone levels are at-7dBFS. Selector Guide 34 PART SAMPLING RATE (Msps) INTEGRATED CDMA Tx FILTERS MAX19710 7.5 No MAX19711 11 Yes MAX19712 22 No MAX19713 45 No ______________________________________________________________________________________ 10-Bit, 7.5Msps, Full-Duplex Analog Front-End VDD = 2.7V TO 3.3V IAP OVDD = 1.8V TO VDD DATA MUX AD0 AD1 AD2 AD3 AD4 AD5 AD6 AD7 AD8 AD9 DATA MUX DA0 DA1 DA2 DA3 DA4 DA5 DA6 DA7 DA8 DA9 SYSTEM CLOCK CLK 10-BIT ADC IAN QAP 10-BIT ADC QAN IDP 10-BIT DAC IDN QDP 10-BIT DAC QDN PROGRAMMABLE OFFSET/GAIN/CM DAC1 12-BIT AUX-DAC DAC2 12-BIT AUX-DAC SERIAL INTERFACE AND SYSTEM CONTROL DOUT 1.024V REFERENCE BUFFER 12-BIT AUX-DAC DAC3 ADC1 ADC2 CS/WAKE SCLK DIN REFIN REFP REFN COM 10-BIT AUX-ADC MAX19710 VDD / 2 OVDD / 2 GND OGND ______________________________________________________________________________________ 35 MAX19710 Functional Diagram Package Information (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.) E DETAIL A 32, 44, 48L QFN.EPS MAX19710 10-Bit, 7.5Msps, Full-Duplex Analog Front-End (NE-1) X e E/2 k e D/2 CL (ND-1) X e D D2 D2/2 b L E2/2 DETAIL B e E2 CL L L1 CL k CL L L e A1 A2 e A PACKAGE OUTLINE 32, 44, 48, 56L THIN QFN, 7x7x0.8mm 21-0144 36 ______________________________________________________________________________________ E 1 2 10-Bit, 7.5Msps, Full-Duplex Analog Front-End PACKAGE OUTLINE 32, 44, 48, 56L THIN QFN, 7x7x0.8mm 21-0144 E 2 2 Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time. Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 37 © 2006 Maxim Integrated Products Jackson Printed USA is a registered trademark of Maxim Integrated Products, Inc. MAX19710 Package Information (continued) (The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information, go to www.maxim-ic.com/packages.)