LTC1591IG

FEATURES s s s LTC1591/LTC1597 14-Bit and 16-Bit Parallel Low Glitch Multiplying DACs with 4-Quadrant Resistors DESCRIPTION The LTC®1591/LTC1597 are pin compatible, parallel input 14-bit and 16-bit multiplying current output DACs that operate from a single 5V supply. INL and DNL are accurate to 1LSB over the industrial temperature range in both 2- and 4quadrant multiplying modes. True 16-bit 4-quadrant multiplication is achieved with on-chip 4-quadrant multiplication resistors. These DACs include an internal deglitcher circuit that reduces the glitch impulse to less than 2nV-s (typ). The asynchronous CLR pin resets the LTC1591/LTC1597 to zero scale and LTC1591-1/LTC1597-1 to midscale. The LTC1591/LTC1597 are available in 28-pin SSOP and PDIP packages and are specified over the industrial temperature range. For serial interface 16-bit current output DACs refer to the LTC1595/LTC1596 data sheet. , LTC and LT are registered trademarks of Linear Technology Corporation. s s s s s s True 16-Bit Performance Over Industrial Temperature Range DNL and INL: 1LSB Max On-Chip 4-Quadrant Resistors Allow Precise 0V to 10V, 0V to – 10V or ±10V Outputs Pin Compatible 14- and 16-Bit Parts Asynchronous Clear Pin LTC1591/LTC1597: Reset to Zero Scale LTC1591-1/LTC1597-1: Reset to Midscale Glitch Impulse < 2nV-s 28-Lead SSOP Package Low Power Consumption: 10µW Typ Power-On Reset APPLICATIONS s s s s Process Control and Industrial Automation Direct Digital Waveform Generation Software-Controlled Gain Adjustment Automatic Test Equipment TYPICAL APPLICATION 16-Bit, 4-Quadrant Multiplying DAC with a Minimum of External Components VREF 5V 0.1µF LTC1591/LTC1591-1 Integral Nonlinearity 1.0 0.8 INTEGRAL NONLINEARITY (LSB) LT®1468 15pF 1 REF 23 4 VCC ROFS ROFS RFB VOUT = – VREF TO VREF INTEGRAL NONLINEARITY (LSB) 5 RFB 15pF 3 R1 R1 16 DATA INPUTS 10 TO 21, 24 TO 27 2 RCOM R2 LTC1597/LTC1597-1 Integral Nonlinearity 1.0 0.8 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 0 49152 32768 16384 DIGITAL INPUT CODE 65535 1591/97 TA03 LTC1597-1 16-BIT DAC DGND WR LD CLR 22 WR LD CLR 9 8 28 + AGND 7 – IOUT1 6 LT1468 1591/97 TA01 U U U VREF = 10V VOUT = ±10V BIPOLAR 0.6 0.4 0.2 0 –0.2 –0.4 –0.6 –0.8 –1.0 0 12288 8192 4096 DIGITAL INPUT CODE 16383 1591/97 TA02 + – VREF = 10V VOUT = ±10V BIPOLAR 1 LTC1591/LTC1597 ABSOLUTE MAXIMUM RATINGS (Note 1) VCC to AGND ............................................... – 0.5V to 7V VCC to DGND .............................................. – 0.5V to 7V AGND to DGND ............................................. VCC + 0.5V DGND to AGND ............................................. VCC + 0.5V REF, ROFS, RFB, R1, RCOM to AGND, DGND .......... ± 25V Digital Inputs to DGND ............... – 0.5V to (VCC + 0.5V) IOUT1 to AGND ............................ – 0.5V to( VCC + 0.5V) Maximum Junction Temperature .......................... 125°C Operating Temperature Range LTC1591C/LTC1591-1C LTC1597C/LTC1597-1C .......................... 0°C to 70°C LTC1591I/LTC1591-1I LTC1597I/LTC1597-1I ....................... – 40°C to 85°C Storage Temperature Range ................ – 65°C to 150°C Lead Temperature (Soldering, 10 sec)................. 300°C PACKAGE/ORDER INFORMATION ORDER PART NUMBER TOP VIEW REF RCOM R1 ROFS RFB IOUT1 AGND LD WR 1 2 3 4 5 6 7 8 9 28 CLR 27 NC 26 NC 25 D0 24 D1 23 VCC 22 DGND 21 D2 20 D3 19 D4 18 D5 17 D6 16 D7 15 D8 N PACKAGE 28-LEAD NARROW PDIP TOP VIEW D13 10 D12 11 D11 12 D10 13 D9 14 G PACKAGE 28-LEAD PLASTIC SSOP LTC1591CG LTC1591CN LTC1591IG LTC1591IN LTC1591-1CG LTC1591-1CN LTC1591-1IG LTC1591-1IN TJMAX = 125°C, θJA = 95°C/ W (G) TJMAX = 125°C, θJA = 70°C/ W (N) Consult factory for Military grade parts. 2 U U W WW U W ORDER PART NUMBER REF RCOM R1 ROFS RFB IOUT1 AGND LD WR 1 2 3 4 5 6 7 8 9 28 CLR 27 D0 26 D1 25 D2 24 D3 23 VCC 22 DGND 21 D4 20 D5 19 D6 18 D7 17 D8 16 D9 15 D10 N PACKAGE 28-LEAD NARROW PDIP D15 10 D14 11 D13 12 D12 13 D11 14 G PACKAGE 28-LEAD PLASTIC SSOP TJMAX = 125°C, θJA = 95°C/ W (G) TJMAX = 125°C, θJA = 70°C/ W (N) LTC1597ACG LTC1597ACN LTC1597BCG LTC1597BCN LTC1597-1ACG LTC1597-1ACN LTC1597-1BCG LTC1597-1BCN LTC1597AIG LTC1597AIN LTC1597BIG LTC1597BIN LTC1597-1AIG LTC1597-1AIN LTC1597-1BIG LTC1597-1BIN LTC1591/LTC1597 ELECTRICAL CHARACTERISTICS VCC = 5V ± 10%, VREF = 10V, IOUT1 = AGND = DGND = 0V, TA = TMIN to TMAX, unless otherwise noted. SYMBOL PARAMETER Accuracy Resolution Monotonicity INL DNL GE Integral Nonlinearity Differential Nonlinearity Gain Error (Note 2) TA = 25°C TMIN to TMAX TA = 25°C TMIN to TMAX Unipolar Mode (Note 3) TA = 25°C TMIN to TMAX Bipolar Mode (Note 3) TA = 25°C TMIN to TMAX Gain Temperature Coefficient Bipolar Zero-Scale Error ILKG PSRR OUT1 Leakage Current Power Supply Rejection Ratio (Note 4) ∆Gain/∆Temperature TA = 25°C TMIN to TMAX (Note 5) TA = 25°C TMIN to TMAX VCC = 5V ± 10 q q q q CONDITIONS LTC1591/-1 LTC1597B/-1B MIN TYP MAX MIN TYP MAX 14 14 ±1 ±1 ±1 ±1 ±4 ±6 ±4 ±6 1 2 ±3 ±5 ±5 ± 15 ± 0.1 ±1 ± 0.4 1 16 16 ±2 ±2 ±1 ±1 ± 16 ± 24 ± 16 ± 24 2 ± 10 ± 16 ±5 ± 15 ±2 LTC1597A/-1A MIN TYP MAX 16 16 ± 0.25 ± 0.35 ± 0.2 ± 0.2 2 3 2 3 1 ±1 ±1 ±1 ±1 ± 16 ± 16 ± 16 ± 16 2 ±5 ±8 ±5 ± 15 ± 0.4 ±2 UNITS Bits Bits LSB LSB LSB LSB LSB LSB LSB LSB ppm/°C LSB LSB nA nA LSB/V q q q q q q VCC = 5V ± 10%, VREF = 10V, IOUT1 = AGND = DGND = 0V, TA = TMIN to TMAX, unless otherwise noted. SYMBOL RREF R1/R2 ROFS, RFB PARAMETER DAC Input Resistance (Unipolar) R1/R2 Resistance (Bipolar) Feedback and Offset Resistances Output Current Settling Time Midscale Glitch Impulse Digital-to-Analog Glitch Impulse Multiplying Feedthrough Error THD Total Harmonic Distortion Output Noise Voltage Density Harmonic Distortion (Digital Waveform Generation) CONDITIONS (Note 6) (Notes 6, 13) (Note 6) (Notes 7, 8) (Note 12) (Note 9) VREF = ±10V, 10kHz Sine Wave (Note 10) (Note 11) Unipolar Mode (Note 14) 2nd Harmonic 3rd Harmonic SFDR Bipolar Mode (Note 14) 2nd Harmonic 3rd Harmonic SFDR q q q MIN 4.5 9 9 TYP 6 12 12 1 2 1 1 108 10 94 101 94 94 101 94 MAX 10 20 20 UNITS kΩ kΩ kΩ µs nV-s nV-s mVP-P dB nV/√Hz dB dB dB dB dB dB Reference Input AC Performance (Note 4) 3 LTC1591/LTC1597 ELECTRICAL CHARACTERISTICS VCC = 5V ± 10%, VREF = 10V, IOUT1 = AGND = DGND = 0V, TA = TMIN to TMAX, unless otherwise noted. SYMBOL COUT PARAMETER Output Capacitance (Note 4) CONDITIONS DAC Register Loaded to All 1s: COUT1 DAC Register Loaded to All 0s: COUT1 q q MIN TYP 115 70 MAX 130 80 UNITS pF pF V Analog Outputs (Note 4) Digital Inputs VIH VIL IIN CIN tDS tDH tWR tLD tCLR tLWD VDD IDD Digital Input High Voltage Digital Input Low Voltage Digital Input Current Digital Input Capacitance Data to WR Setup Time Data to WR Hold Time WR Pulse Width LD Pulse Width Clear Pulse Width WR to LD Delay Time Supply Voltage Supply Current Digital Inputs = 0V or VCC (Note 4) VIN = 0V q q q q 2.4 0.8 0.001 ±1 8 60 0 60 110 60 0 4.5 5 5.5 10 20 –12 25 55 40 V µA pF ns ns ns ns ns ns V µA Timing Characteristics q q q q q q Power Supply q q The q denotes specifications that apply over the full operating temperature range. Note 1: Absolute Maximum Values are those beyond which the life of a device may be impaired. Note 2: ± 1LSB = ± 0.006% of full scale = ± 61ppm of full scale for the LTC1591/LTC1591-1. ± 1LSB = ± 0.0015% of full scale = ± 15.3ppm of full scale for the LTC1597/LTC1597-1. Note 3: Using internal feedback resistor. Note 4: Guaranteed by design, not subject to test. Note 5: I(OUT1) with DAC register loaded to all 0s. Note 6: Typical temperature coefficient is 100ppm/°C. Note 7: IOUT1 load = 100Ω in parallel with 13pF. Note 8: To 0.006% for a full-scale change, measured from the rising edge of LD for the LTC1591/LTC1591-1. To 0.0015% for a full-scale change, measured from the rising edge of LD for the LTC1597/LTC1597-1. Note 9: VREF = 0V. DAC register contents changed from all 0s to all 1s or all 1s to all 0s. Note 10: VREF = 6VRMS at 1kHz. DAC register loaded with all 1s. Note 11: Calculation from en = √4kTRB where: k = Boltzmann constant (J/°K), R = resistance (Ω), T = temperature (°K), B = bandwidth (Hz). Note 12: Midscale transition code: 01 1111 1111 1111 to 10 0000 0000 0000 for the LTC1591/LTC1591-1 and 0111 1111 1111 1111 to 1000 0000 0000 0000 for the LTC1597/LTC1597-1. Note 13: R1 and R2 are measured between R1 and RCOM, REF and RCOM. Note 14: Measured using the LT1468 op amp in unipolar mode for I/V converter and LT1468 I/V and LT1001 reference inverter in bipolar mode. Sample Rate = 50kHz, Signal Frequency = 1kHz, VREF = 5V, TA = 25°C. 4 LTC1591/LTC1597 TYPICAL PERFOR A CE CHARACTERISTICS Midscale Glitch Impulse 40 30 OUTPUT VOLTAGE (mV) SIGNAL/(NOISE + DISTORTION) (dB) USING AN LT1468 CFEEDBACK = 30pF VREF = 10V LD PULSE 5V/DIV 20 10 0 –10 –20 – 30 – 40 0 0.2 0.4 0.6 TIME (µs) 0.8 1.0 1591/97 G01 1nV-s TYPICAL Bipolar Multiplying Mode Signal-to-(Noise + Distortion) vs Frequency, Code = All Zeros – 40 SIGNAL/(NOISE + DISTORTION) (dB) SIGNAL/(NOISE + DISTORTION) (dB) – 50 – 60 – 70 – 80 VCC = 5V USING TWO LT1468s CFEEDBACK = 15pF REFERENCE = 6VRMS – 90 80kHz FILTER 30kHz FILTER 10 100 1k 10k FREQUENCY (Hz) 100k 1591/97 G04 –100 –110 Supply Current vs Input Voltage 5 VCC = 5V ALL DIGITAL INPUTS TIED TOGETHER LOGIC THRESHOLD (V) 4 SUPPLY CURRENT (mA) 3 2 1 0 0 1 UW (LTC1591/LTC1597) Unipolar Multiplying Mode Signal-to-(Noise + Distortion) vs Frequency – 40 – 50 – 60 – 70 – 80 500kHz FILTER – 90 80kHz FILTER 30kHz FILTER 10 100 1k 10k FREQUENCY (Hz) 100k 1591/97 G03 Full-Scale Settling Waveform VCC = 5V USING AN LT1468 CFEEDBACK = 30pF REFERENCE = 6VRMS GATED SETTLING WAVEFORM 500µV/DIV 500ns/DIV USING LT1468 OP AMP CFEEDBACK = 20pF 0V to 10V STEP 1591/97 G02 –100 –110 Bipolar Multiplying Mode Signal-to-(Noise + Distortion) vs Frequency, Code = All Ones – 40 – 50 – 60 – 70 – 80 500kHz FILTER – 90 80kHz FILTER 30kHz FILTER –110 10 100 1k 10k FREQUENCY (Hz) 100k 1591/97 G05 VCC = 5V USING TWO LT1468s CFEEDBACK = 15pF REFERENCE = 6VRMS 500kHz FILTER –100 Logic Threshold vs Supply Voltage 3.0 2.5 2.0 1.5 1.0 0.5 0 3 2 INTPUT VOLTAGE (V) 4 5 1591/97 G06 0 1 2 3 4 5 SUPPLY VOLTAGE (V) 6 7 1591/97 G07 5 LTC1591/LTC1597 TYPICAL PERFOR A CE CHARACTERISTICS (LTC1591) Integral Nonlinearity (INL) 1.0 1.0 DIFFERENTIAL NONLINEARITY (LSB) 0.8 INTEGRAL NONLINEARITY (LSB) 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 0 12280 8192 4096 DIGITAL INPUT CODE 16383 1591 G01 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 0 12280 8192 4096 DIGITAL INPUT CODE 16383 1591 G02 INTEGRAL NONLINEARITY (LSB) Integral Nonlinearity vs Reference Voltage in Bipolar Mode 1.0 1.0 DIFFERENTIAL NONLINEARITY (LSB) 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 –10 – 8 – 6 – 4 – 2 0 2 4 6 REFERENCE VOLTAGE (V) 8 10 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 –10 – 8 – 6 – 4 – 2 0 2 4 6 REFERENCE VOLTAGE (V) 8 10 DIFFERENTIAL NONLINEARITY (LSB) 0.8 INTEGRAL NONLINEARITY (LSB) Integral Nonlinearity vs Supply Voltage in Unipolar Mode 1.0 0.8 INTEGRAL NONLINEARITY (LSB) INTEGRAL NONLINEARITY (LSB) 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 0 1 4 3 2 5 SUPPLY VOLTAGE (V) 6 7 1591 G07 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 0 1 4 3 2 5 SUPPLY VOLTAGE (V) 6 7 1591 G08 DIFFERENTIAL NONLINEARITY (LSB) VREF = 10V VREF = 2.5V VREF = 10V VREF = 2.5V 6 UW Differential Nonlinearity (DNL) 1.0 0.8 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 0.8 Integral Nonlinearity vs Reference Voltage in Unipolar Mode –1.0 –10 – 8 – 6 – 4 – 2 0 2 4 6 REFERENCE VOLTAGE (V) 8 10 1591 G03 Differential Nonlinearity vs Reference Voltage in Unipolar Mode 1.0 0.8 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 0.8 Differential Nonlinearity vs Reference Voltage in Bipolar Mode –1.0 –10 – 8 – 6 – 4 – 2 0 2 4 6 REFERENCE VOLTAGE (V) 8 10 1591 G04 1591 G05 1591 G06 Integral Nonlinearity vs Supply Voltage in Bipolar Mode 1.0 0.8 1.0 0.8 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 Differential Nonlinearity vs Supply Voltage in Unipolar Mode VREF = 10V VREF = 2.5V VREF = 2.5V VREF = 10V VREF = 10V VREF = 2.5V VREF = 10V VREF = 2.5V 0 1 4 3 2 5 SUPPLY VOLTAGE (V) 6 7 1591 G09 LTC1591/LTC1597 TYPICAL PERFOR A CE CHARACTERISTICS (LTC1591) Differential Nonlinearity vs Supply Voltage in Bipolar Mode 1.0 DIFFERENTIAL NONLINEARITY (LSB) 0.8 0.6 ATTENUATION (dB) 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 VREF = 2.5V VREF = 10V VREF = 2.5V VREF = 10V –1.0 0 1 4 3 2 5 SUPPLY VOLTAGE (V) 6 7 1591 G10 Bipolar Multiplying Mode Frequency Response vs Digital Code 0 ALL BITS ON D13 AND D12 ON D13 AND D11 ON D13 AND D10 ON D13 AND D9 ON D13 AND D8 ON D13 AND D7 ON D13 AND D6 ON D13 AND D5 ON D13 AND D4 ON D13 AND D3 ON D13 AND D2 ON D13 AND D1 ON D13 AND D0 ON D13 ON* – 20 ATTENUATION (dB) – 40 ATTENUATION (dB) – 60 – 80 CODES FROM MIDSCALE TO FULL SCALE – 100 10 100 1k 10k 100k FREQUENCY (Hz) 1M 10M 1591 G12 *DAC ZERO VOLTAGE OUTPUT LIMITED BY BIPOLAR ZERO ERROR TO – 84dB TYPICAL (–70dB MAX) VREF + LT1468 – 12pF 12pF 15pF 3 2 LTC1591 145 VOUT UW Unipolar Multiplying Mode Frequency Response vs Digital Code 0 – 20 – 40 – 60 – 80 ALL BITS ON D13 ON D12 ON D11 ON D10 ON D9 ON D8 ON D7 ON D6 ON D5 ON D4 ON D3 ON D2 ON D1 ON D0 ON – 100 ALL BITS OFF – 120 100 1k 10k 100k FREQUENCY (Hz) 1M 10M 1591G11 VREF 32145 LTC1591 7 22 6 30pF – LT1468 + VOUT Bipolar Multiplying Mode Frequency Response vs Digital Code 0 ALL BITS OFF D12 ON D12 AND D11 ON D12 TO D10 ON D12 TO D9 ON D12 TO D8 ON D12 TO D7 ON D12 TO D6 ON D12 TO D5 ON D12 TO D4 ON D12 TO D3 ON D12 TO D2 ON D12 TO D1 ON D12 TO D0 ON D13 ON* – 20 – 40 – 60 – 80 – 100 10 CODES FROM MIDSCALE TO ZERO SCALE 100 100k 1k 10k FREQUENCY (Hz) 1M 10M 1591G13 *DAC ZERO VOLTAGE OUTPUT LIMITED BY BIPOLAR ZERO ERROR TO – 84dB TYPICAL (–70dB MAX) VREF + LT1468 – 12pF 12pF 15pF 3 6 7 22 VOUT 2 LTC1591 145 – LT1468 + 6 7 22 – LT1468 + 7 LTC1591/LTC1597 TYPICAL PERFOR A CE CHARACTERISTICS Integral Nonlinearity (INL) 1.0 DIFFERENTIAL NONLINEARITY (LSB) 0.8 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 0 49152 32768 16384 DIGITAL INPUT CODE 65535 1597 G01 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 0 49152 32768 16384 DIGITAL INPUT CODE 65535 1597 G02 INTEGRAL NONLINEARITY (LSB) INTEGRAL NONLINEARITY (LSB) Integral Nonlinearity vs Reference Voltage in Bipolar Mode 1.0 1.0 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 –10 – 8 – 6 – 4 – 2 0 2 4 6 REFERENCE VOLTAGE (V) 8 10 DIFFERENTIAL NONLINEARITY (LSB) DIFFERENTIAL NONLINEARITY (LSB) 0.8 INTEGRAL NONLINEARITY (LSB) Integral Nonlinearity vs Supply Voltage in Unipolar Mode 1.0 0.8 INTEGRAL NONLINEARITY (LSB) INTEGRAL NONLINEARITY (LSB) DIFFERENTIAL NONLINEARITY (LSB) 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 2 3 4 5 6 SUPPLY VOLTAGE (V) 7 1597 G07 VREF = 10V VREF = 2.5V VREF = 10V VREF = 2.5V 8 UW (LTC1597) Integral Nonlinearity vs Reference Voltage in Unipolar Mode 1.0 0.8 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 –10 – 8 – 6 – 4 – 2 0 2 4 6 REFERENCE VOLTAGE (V) 8 10 Differential Nonlinearity (DNL) 1.0 0.8 1597 G03 Differential Nonlinearity vs Reference Voltage in Unipolar Mode 1.0 0.8 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 0.8 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 –10 – 8 – 6 – 4 – 2 0 2 4 6 REFERENCE VOLTAGE (V) 8 10 Differential Nonlinearity vs Reference Voltage in Bipolar Mode –1.0 –10 – 8 – 6 – 4 – 2 0 2 4 6 REFERENCE VOLTAGE (V) 8 10 1597 G04 1597 G05 1597 G06 Integral Nonlinearity vs Supply Voltage in Bipolar Mode 2.0 1.5 1.0 0.5 0 VREF = 10V VREF = 2.5V –1.0 –1.5 –2.0 2 3 4 5 6 SUPPLY VOLTAGE (V) 7 1597 G08 Differential Nonlinearity vs Supply Voltage in Unipolar Mode 1.0 0.8 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 –1.0 2 3 4 5 6 SUPPLY VOLTAGE (V) 7 1597 G09 VREF = 10V VREF = 2.5V VREF = 10V VREF = 2.5V – 0.5 VREF = 10V VREF = 2.5V LTC1591/LTC1597 TYPICAL PERFOR A CE CHARACTERISTICS (LTC1597) Differential Nonlinearity vs Supply Voltage in Bipolar Mode 1.0 DIFFERENTIAL NONLINEARITY (LSB) 0 – 20 ATTENUATION (dB) – 40 – 60 – 80 0.8 0.6 0.4 0.2 0 – 0.2 – 0.4 – 0.6 – 0.8 VREF = 2.5V VREF = 2.5V VREF = 10V VREF = 10V –1.0 2 3 4 5 6 SUPPLY VOLTAGE (V) 7 1597 G10 Bipolar Multiplying Mode Frequency Response vs Digital Code 0 – 20 ALL BITS ON D15 AND D14 ON D15 AND D13 ON D15 AND D12 ON D15 AND D11 ON D15 AND D10 ON D15 AND D9 ON D15 AND D8 ON D15 AND D7 ON D15 AND D6 ON D15 AND D5 ON D15 AND D4 ON D15 AND D3 ON D15 AND D2 ON ATTENUATION (dB) – 40 – 60 – 80 ATTENUATION (dB) – 100 10 100 *DAC ZERO VOLTAGE OUTPUT LIMITED BY BIPOLAR ZERO ERROR TO – 96dB TYPICAL (–78dB MAX, A GRADE) VREF + LT1468 – 12pF 12pF 15pF 3 2 LTC1597 145 6 7 22 VOUT UW Unipolar Multiplying Mode Frequency Response vs Digital Code ALL BITS ON D15 ON D14 ON D13 ON D12 ON D11 ON D10 ON D9 ON D8 ON D7 ON D6 ON D5 ON D4 ON D3 ON D2 ON D1 ON D0 ON ALL BITS OFF – 100 – 120 100 1k 10k 100k FREQUENCY (Hz) 1M 10M 1597G11 VREF 32145 LTC1597 7 22 6 30pF – LT1468 + VOUT Bipolar Multiplying Mode Frequency Response vs Digital Code 0 – 20 ALL BITS OFF D14 ON D14 AND D13 ON D14 TO D12 ON D14 TO D11 ON D14 TO D10 ON D14 TO D9 ON D14 TO D8 ON D14 TO D7 ON D14 TO D6 ON D14 TO D5 ON D14 TO D4 ON D14 TO D3 ON D14 TO D2 ON D14 TO D1 ON – 40 – 60 CODES FROM MIDSCALE TO FULL SCALE – 80 D15 AND D1 ON D15 AND D0 ON D15 ON* CODES FROM MIDSCALE TO ZERO SCALE D14 TO D0 ON – 100 1M 10M 1597 G12 D15 ON* 1k 10k 100k FREQUENCY (Hz) 10 100 100k 1k 10k FREQUENCY (Hz) 1M 10M 1597 G13 *DAC ZERO VOLTAGE OUTPUT LIMITED BY BIPOLAR ZERO ERROR TO – 96dB TYPICAL (–78dB MAX, A GRADE) VREF + LT1468 – 12pF 12pF 15pF 3 2 LTC1597 145 6 7 22 VOUT – LT1468 + – LT1468 + 9 LTC1591/LTC1597 PIN FUNCTIONS LTC1591 REF (Pin 1): Reference Input and 4-Quadrant Resistor R2. Typically ±10V, accepts up to ± 25V. In 2-Quadrant mode this is the reference input. In 4-quadrant mode, this pin is driven by external inverting reference amplifier. RCOM (Pin 2): Center Tap Point of the Two 4-Quadrant Resistors R1 and R2. Normally tied to the inverting input of an external amplifier in 4-quadrant operation, otherwise shorted to the REF pin. See Figures 1a and 2a. R1 (Pin 3): 4-Quadrant Resistor R1. In 2-quadrant operation short to the REF pin. In 4-quadrant mode tie to ROFS (Pin 4). ROFS (Pin 4): Bipolar Offset Resistor. Typically swings ± 10V, accepts up to ± 25V. In 2-quadrant operation tie to RFB. In 4-quadrant operation tie to R1. RFB (Pin 5): Feedback Resistor. Normally tied to the output of the current to voltage converter op amp. Swings to ± VREF. VREF is typically ± 10V. IOUT1 (Pin 6): DAC Current Output. Tie to the inverting input of the current to voltage converter op amp. AGND (Pin 7): Analog Ground. Tie to ground. LD (Pin 8): DAC Digital Input Load Control Input. When LD is taken to a logic high, data is loaded from the input register into the DAC register, updating the DAC output. WR (Pin 9):DAC Digital Write Control Input. When WR is taken to a logic low, data is loaded from the digital input pins into the 14-bit wide input register. DB13 to D2 (Pins 10 to 21): Digital Input Data Bits. DGND (Pin 22): Digital Ground. Tie to ground. VCC (Pin 23): The Positive Supply Input. 4.5V ≤ VCC ≥ 5.5V. Requires a bypass capacitor to ground. DB1, DB0 (Pins 24, 25): Digital Input Data Bits. NC (Pins 26, 27): No Connect. CLR (Pin 28):Digital Clear Control Function for the DAC. When CLR is taken to a logic low, it sets the DAC output and all internal registers to zero code for the LTC1591 and midscale code for the LTC1591-1. IOUT1 (Pin 6): DAC Current Output. Tie to the inverting input of the current to voltage converter op amp. AGND (Pin 7): Analog Ground. Tie to ground. LD (Pin 8): DAC Digital Input Load Control Input. When LD is taken to a logic high, data is loaded from the input register into the DAC register, updating the DAC output. WR (Pin 9):DAC Digital Write Control Input. When WR is taken to a logic low, data is loaded from the digital input pins into the 16-bit wide input register. DB15 to D4 (Pins 10 to 21): Digital Input Data Bits. DGND (Pin 22): Digital Ground. Tie to ground. VCC (Pin 23): The Positive Supply Input. 4.5V ≤ VCC ≥ 5.5V. Requires a bypass capacitor to ground. DB3 to DB0 (Pins 24 to 27): Digital Input Data Bits. CLR (Pin 28):Digital Clear Control Function for the DAC. When CLR is taken to a logic low, it sets the DAC output and all internal registers to zero code for the LTC1597 and midscale code for the LTC1597-1. LTC1597 REF (Pin 1): Reference Input and 4-Quadrant Resistor R2. Typically ±10V, accepts up to ± 25V. In 2-Quadrant mode this is the reference input. In 4-quadrant mode, this pin is driven by external inverting reference amplifier. RCOM (Pin 2): Center Tap Point of the Two 4-Quadrant Resistors R1 and R2. Normally tied to the inverting input of an external amplifier in 4-quadrant operation, otherwise shorted to the REF pin. See Figures 1b and 2b. R1 (Pin 3): 4-Quadrant Resistor R1. In 2-quadrant operation short to the REF pin. In 4-quadrant mode tie to ROFS (Pin 4). ROFS (Pin 4): Bipolar Offset Resistor. Typically swings ± 10V, accepts up to ± 25V. In 2-quadrant operation tie to RFB. In 4-quadrant operation tie to R1. RFB (Pin 5): Feedback Resistor. Normally tied to the output of the current to voltage converter op amp. Swings to ± VREF. VREF is typically ± 10V. 10 U U U LTC1591/LTC1597 TRUTH TABLE Table 1 CONTROL INPUTS CLR WR LD 0 1 1 1 1 1 1 0 X 0 1 0 X 0 1 1 REGISTER OPERATION Reset Input and DAC Register to All 0s for LTC1591/LTC1597 and Midscale for LTC1591-1/LTC1597-1 (Asynchronous Operation) Load Input Register with All 14/16 Data Bits Load DAC Register with the Contents of the Input Register Input and DAC Register Are Transparent CLK = LD and WR Tied Together. The 14/16 Data Bits Are Loaded into the Input Register on the Falling Edge of the CLK and Then Loaded into the DAC Register on the Rising Edge of the CLK No Register Operation BLOCK DIAGRA SM LTC1591 48k REF 1 12k RCOM 2 12k R1 3 48k 48k 48k 48k 48k 48k 48k 96k 96k 96k 96k 12k 12k 48k 5 RFB 4 ROFS VCC 23 DECODER LD 8 WR 9 W 6 IOUT1 7 AGND 22 DGND D12 D11 D10 D9 ••• D0 (LSB) LOAD D13 (MSB) DAC REGISTER RST 28 CLR WR INPUT REGISTER RST 1591 BD 10 D13 11 D12 •••• 21 D2 24 D1 25 D0 26 NC 27 NC 11 LTC1591/LTC1597 BLOCK DIAGRA SM LTC1597 48k REF 1 12k RCOM 2 12k R1 3 48k 48k 48k 48k 48k 48k 48k 96k 96k 96k 96k 12k 12k 4 ROFS 48k 5 RFB VCC 23 DECODER LD 8 WR 9 TI I G DIAGRA 12 W W 6 IOUT1 7 AGND 22 DGND D14 D13 D12 D11 ••• D0 (LSB) RST LOAD D15 (MSB) DAC REGISTER 28 CLR WR INPUT REGISTER RST 1597 BD 10 D15 11 D14 •••• 21 D4 24 D3 25 D2 26 D1 27 D0 UW tWR WR DATA tDS tDH tLWD LD tLD tCLR CLR 1591/97TD LTC1591/LTC1597 APPLICATIONS INFORMATION Description The LTC1591/LTC1597 are 14-/16-bit multiplying, current output DACs with a full parallel 14-/16-bit digital interface. The devices operate from a single 5V supply and provide both unipolar 0V to – 10V or 0V to 10V and bipolar ± 10V output ranges from a 10V or –10V reference input. They have three additional precision resistors on chip for bipolar operation. Refer to the block diagrams regarding the following description. The 14-/16-bit DACs consist of a precision R-2R ladder for the 11/13LSBs. The 3MSBs are decoded into seven segments of resistor value R. Each of these segments and the R-2R ladder carries an equally weighted current of one eighth of full scale. The feedback resistor RFB and 4-quadrant resistor ROFS have a value of R/4. 4-quadrant resistors R1 and R2 have a magnitude of R/4. R1 and R2 together with an external op amp (see Figure 2) inverts the reference input voltage and applies it to the 14-/16-bit DAC input REF, in 4-quadrant operation. The REF pin presents a constant input impedance of R/8 in unipolar mode and R/12 in bipolar mode. The output impedance of the current output pin IOUT1 varies with DAC input code. The IOUT1 capacitance due to the NMOS current steering switches also varies with input code from 70pF to 115pF. An added feature of these devices, especially for waveform generation, is a proprietary deglitcher that reduces glitch energy to below 2nV-s over the DAC output voltage range. Digital Section The LTC1591/LTC1597 are 14-/16-bit wide full parallel data bus inputs. The devices are double-buffered with two 14-/16-bit registers. The double-buffered feature permits the update of several DACs simultaneously. The input register is loaded directly from a 16-bit microprocessor bus when the WR pin is brought to a logic low level. The second register (DAC register) is updated with the data from the input register when the LD pin is brought to a logic high level. Updating the DAC register updates the DAC output with the new data. To make both registers transparent for flowthrough mode, tie WR low and LD high. However, this defeats the deglitcher operation and output glitch impulse may increase. The deglitcher is activated on the rising edge of the LD pin. The versatility of the interface also allows the use of the input and DAC registers in a master slave or edge-triggered configuration. This mode of operation occurs when WR and LD are tied together. The asynchronous clear pin resets the LTC1591/LTC1597 to zero scale and the LTC1591-1/ LTC1597-1 to midscale. CLR resets both the input and DAC registers. These devices also have a power-on reset. Table 1 shows the truth table for the LTC1591/LT1597. Unipolar Mode (2-Quadrant Multiplying, VOUT = 0V to – VREF) The LTC1591/LTC1597 can be used with a single op amp to provide 2-quadrant multiplying operation as shown in Figure 1. With a fixed – 10V reference, the circuits shown give a precision unipolar 0V to 10V output swing. 5V 0.1µF VREF 3 R1 R1 14 DATA INPUTS 10 TO 21, 24, 25 WR LD CLR WR LD CLR 9 8 28 NC 26 NC 27 2 RCOM R2 1 REF 23 VCC 4 ROFS ROFS RFB 5 RFB 33pF IOUT1 LTC1591 14-BIT DAC 6 DGND 22 Figure 1a. Unipolar Operation (2-Quadrant Multiplication) VOUT = 0V to – VREF + AGND 7 – U W U U Unipolar Binary Code Table VOUT = 0V TO –VREF DIGITAL INPUT BINARY NUMBER IN DAC REGISTER MSB 1111 1000 0000 0000 1111 0000 0000 0000 1111 0000 0000 0000 LSB 11 00 01 00 –VREF (16,383/16,384) –VREF (8,192/16,384) = –VREF/ 2 –VREF (1/16,384) 0V 1591/97 F01a LT1001 ANALOG OUTPUT VOUT 13 LTC1591/LTC1597 APPLICATIONS INFORMATION 5V 0.1µF VREF 3 R1 R1 16 DATA INPUTS 10 TO 21, 24 TO 27 WR LD CLR WR LD CLR 9 8 28 2 RCOM R2 1 REF 23 VCC 4 ROFS ROFS RFB 5 RFB 33pF IOUT1 LTC1597 16-BIT DAC 6 DGND 22 Figure 1b. Unipolar Operation (2-Quadrant Multiplication) VOUT = 0V to – VREF Bipolar Mode (4-Quadrant Multiplying, VOUT = – VREF to VREF) The LTC1591/LTC1597 contain on chip all the 4-quadrant resistors necessary for bipolar operation. 4-quadrant multiplying operation can be achieved with a minimum of external components, a capacitor and a dual op amp, as shown in Figure 2. With a fixed 10V reference, the circuit shown gives a precision bipolar – 10V to 10V output swing. Op Amp Selection Because of the extremely high accuracy of the 14-/16-bit LTC1591/LTC1597, thought should be given to op amp selection in order to achieve the exceptional performance of which the part is capable. Fortunately, the sensitivity of INL and DNL to op amp offset has been greatly reduced compared to previous generations of multiplying DACs. Op amp offset will contribute mostly to output offset and gain and will have minimal effect on INL and DNL. For the LTC1597, a 500µV op amp offset will cause about 0.55LSB INL degradation and 0.15LSB DNL degradation with a 10V full-scale range. The main effects of op amp offset will be a degradation of zero-scale error equal to the op amp 14 + AGND 7 – U W U U Unipolar Binary Code Table VOUT = 0V TO –VREF DIGITAL INPUT BINARY NUMBER IN DAC REGISTER MSB 1111 1000 0000 0000 1111 0000 0000 0000 1111 0000 0000 0000 LSB 1111 0000 0001 0000 –VREF (65,535/65,536) –VREF (32,768/65,536) = –VREF/ 2 –VREF (1/65,536) 0V 1591/97 F01b LT1001 ANALOG OUTPUT VOUT offset, and a degradation of full-scale error equal to twice the op amp offset. For the LTC1597, the same 500µV op amp offset (2mV offset for LTC1591) will cause a 3.3LSB zero-scale error and a 6.5LSB full-scale error with a 10V full-scale range. Op amp input bias current (IBIAS) contributes only a zeroscale error equal to IBIAS(RFB/ROFS) = IBIAS(6k). For a thorough discussion of 16-bit DAC settling time and op amp selection, refer to Application Note 74, “Component and Measurement Advances Ensure 16-Bit DAC Settling Time.” Reference Input and Grounding For optimum performance the reference input of the LTC1597 should be driven by a source impedance of less than 1kΩ. However, these DACs have been designed to minimize source impedance effects. An 8kΩ source impedance degrades both INL and DNL by 0.2LSB. As with any high resolution converter, clean grounding is important. A low impedance analog ground plane and star grounding should be used. AGND must be tied to the star ground with as low a resistance as possible. LTC1591/LTC1597 APPLICATIONS INFORMATION VREF 5V 0.1µF 1/2 LT1112 3 R1 R1 14 DATA INPUTS 10 TO 21, 24, 25 2 RCOM R2 1 REF 23 4 VCC ROFS ROFS RFB LTC1591-1 14-BIT DAC AGND DGND 22 7 WR LD CLR WR LD CLR 9 8 28 NC 26 NC 27 Figure 2a. Bipolar Operation (4-Quadrant Multiplication) VOUT = – VREF to VREF VREF 5V 0.1µF 1/2 LT1112 3 R1 R1 16 DATA INPUTS 10 TO 21, 24 TO 27 2 RCOM R2 1 REF 23 4 VCC ROFS ROFS RFB 5 RFB 33pF IOUT1 6 LTC1597-1 16-BIT DAC AGND DGND 22 7 1/2 LT1112 WR LD CLR WR LD CLR 9 8 28 Figure 2b. Bipolar Operation (4-Quadrant Multiplication) VOUT = – VREF to VREF + – + – U 5 W U U + – RFB 33pF IOUT1 6 Bipolar Offset Binary Code Table VOUT = –VREF TO VREF DIGITAL INPUT BINARY NUMBER IN DAC REGISTER MSB 1111 1000 1000 0111 0000 1111 0000 0000 1111 0000 1111 0000 0000 1111 0000 LSB 11 01 00 11 00 VREF (8,191/8,192) VREF (1/8,192) 0V –VREF (1/8,192) –VREF 1591/97 F02a ANALOG OUTPUT VOUT 1/2 LT1112 + – Bipolar Offset Binary Code Table VOUT = –VREF TO VREF DIGITAL INPUT BINARY NUMBER IN DAC REGISTER MSB 1111 1000 1000 0111 0000 1111 0000 0000 1111 0000 1111 0000 0000 1111 0000 LSB 1111 0001 0000 1111 0000 VREF (32,767/32,768) VREF (1/32,768) 0V –VREF (1/32,768) –VREF 1591/97 F02b ANALOG OUTPUT VOUT 15 LTC1591/LTC1597 TYPICAL APPLICATIONS Noninverting Unipolar Operation (2-Quadrant Multiplication) VOUT = 0V to VREF 2 RCOM VREF 3 R1 R1 16 DATA INPUTS 10 TO 21, 24 TO 27 WR LD CLR WR LD CLR 9 8 28 R2 LTC1597 16-BIT DAC AGND DGND 22 7 1591/97 F06 16 + – U + – 5V 0.1µF 1/2 LT1112 1 REF 23 4 VCC ROFS ROFS RFB 5 RFB 33pF IOUT1 6 1/2 LT1112 VOUT = 0V TO VREF LTC1591/LTC1597 TYPICAL APPLICATIONS 16-Bit VOUT DAC Programmable Unipolar/Bipolar Configuration UNIPOLAR/ BIPOLAR LT1236A-10 3 R1 R1 16 DATA INPUTS 10 TO 21, 24 TO 27 2 RCOM R2 LTC1597 16-BIT DAC DGND WR LD CLR 22 1591/97 F04 WR LD CLR 9 8 28 + AGND 7 – + 4 6 LT1001 – 15V 2 + – U 16 15 14 LTC203AC 1 2 3 LT1468 5V 0.1µF 1 23 REF VCC 4 ROFS ROFS RFB 5 RFB 15pF IOUT1 6 LT1468 VOUT 17 LTC1591/LTC1597 TYPICAL APPLICATIONS Digital Waveform Generator LT1001 3 PHASE ACCUMULATOR n R1 R1 FREQUENCY CONTROL SERIAL OR BYTE LOAD REGISTER PARALLEL n DELTA PHASE REGISTER M n Σ n PHASE REGISTER CLOCK n n = 24 TO 32 BITS fO PHASE TRUNCATION 16 BITS 10 TO 21, 24 TO 27 WR LD CLR 9 8 28 DGND 22 1591/97 F05 18 + SIN ROM LOOKUP TABLE 16 DATA INPUTS LTC1597 16-BIT DAC AGND 7 – – + U 15V 2 LT1236A-10 4 6 5V 0.1µF 2 RCOM R2 1 REF 23 4 VCC ROFS ROFS RFB 5 RFB 15pF IOUT1 6 LT1468 LOWPASS FILTER fO = (M)(fC) 2n LTC1591/LTC1597 PACKAGE DESCRIPTION 0.205 – 0.212** (5.20 – 5.38) 0.005 – 0.009 (0.13 – 0.22) 0.022 – 0.037 (0.55 – 0.95) *DIMENSIONS DO NOT INCLUDE MOLD FLASH. MOLD FLASH SHALL NOT EXCEED 0.006" (0.152mm) PER SIDE **DIMENSIONS DO NOT INCLUDE INTERLEAD FLASH. INTERLEAD FLASH SHALL NOT EXCEED 0.010" (0.254mm) PER SIDE 0.300 – 0.325 (7.620 – 8.255) 0.020 (0.508) MIN 0.009 – 0.015 (0.229 – 0.381) ( +0.035 0.325 –0.015 8.255 +0.889 –0.381 ) *THESE DIMENSIONS DO NOT INCLUDE MOLD FLASH OR PROTRUSIONS. MOLD FLASH OR PROTRUSIONS SHALL NOT EXCEED 0.010 INCH (0.254mm) Information furnished by Linear Technology Corporation is believed to be accurate and reliable. However, no responsibility is assumed for its use. Linear Technology Corporation makes no representation that the interconnection of its circuits as described herein will not infringe on existing patent rights. U Dimensions in inches (millimeters) unless otherwise noted. G Package 28-Lead Plastic SSOP (0.209) (LTC DWG # 05-08-1640) 0.397 – 0.407* (10.07 – 10.33) 28 27 26 25 24 23 22 21 20 19 18 17 16 15 0.301 – 0.311 (7.65 – 7.90) 1 2 3 4 5 6 7 8 9 10 11 12 13 14 0.068 – 0.078 (1.73 – 1.99) 0° – 8° 0.0256 (0.65) BSC 0.010 – 0.015 (0.25 – 0.38) 0.002 – 0.008 (0.05 – 0.21) G28 SSOP 0694 N Package 28-Lead PDIP (Narrow 0.300) (LTC DWG # 05-08-1510) 1.370* (34.789) MAX 28 27 26 25 24 23 22 21 20 19 18 17 16 15 0.255 ± 0.015* (6.477 ± 0.381) 1 0.130 ± 0.005 (3.302 ± 0.127) 2 3 4 5 6 7 8 9 10 11 12 13 14 0.045 – 0.065 (1.143 – 1.651) 0.065 (1.651) TYP 0.005 (0.127) MIN 0.100 ± 0.010 (2.540 ± 0.254) 0.018 ± 0.003 (0.457 ± 0.076) N28 1197 0.125 (3.175) MIN 19 LTC1591/LTC1597 TYPICAL APPLICATION 17-Bit Sign Magnitude DAC with Bipolar Zero Error of 140µV (0.92LSB at 17 Bits) at 25°C 16 15V 2 1 6 5V 0.1µF LT1468 2 3 LT1236A-10 4 3 SIGN BIT R1 R1 16 DATA INPUTS 10 TO 21, 24 TO 27 2 RCOM R2 LTC1597 16-BIT DAC DGND WR LD CLR 22 1591/97 F03 WR LD CLR 9 8 28 RELATED PARTS PART NUMBER Op Amps LT1001 LT1112 LT1468 DACs LTC1595/LTC1596 LTC1650 LTC1658 ADCs LTC1418 LTC1604 LTC1605 References LT1236 DESCRIPTION Precision Operational Amplifier Dual Low Power, Precision Picoamp Input Op Amp 90MHz, 22V/µs, 16-Bit Accurate Op Amp Serial 16-Bit Current Output DACs Serial 16-Bit Voltage Output DAC Serial 14-Bit Voltage Output DAC 14-Bit, 200ksps 5V Sampling ADC 16-Bit, 333ksps Sampling ADC Single 5V, 16-Bit 100ksps ADC Precision Reference COMMENTS Low Offset, Low Drift Low Offset, Low Drift Precise, 1µs Settling to 0.0015% Low Glitch, ±1LSB Maximum INL, DNL Low Noise and Glitch Rail-to-Rail VOUT Low Power, 8-Lead MSOP Rail-to-Rail VOUT 16mW Dissipation, Serial and Parallel Outputs ±2.5V Input, SINAD = 90dB, THD = 100dB Low Power, ±10V Inputs Ultralow Drift, 5ppm/°C, High Accuracy 0.05% 20 Linear Technology Corporation 1630 McCarthy Blvd., Milpitas, CA 95035-7417 (408)432-1900 q FAX: (408) 434-0507 q www.linear-tech.com © LINEAR TECHNOLOGY CORPORATION 1998 + AGND 7 – + – U 15 14 LTC203AC 15pF 1 REF 23 4 VCC ROFS ROFS RFB 5 RFB 20pF IOUT1 6 LT1468 VOUT 15917f LT/TP 1298 4K • PRINTED IN USA