7872 14-Bit A/D Converter AGND CREF REF OUT VIN VDD VDD 12 11 13 14 9 16 TRACK/HOLD R R COMP 3V REFERENCE 3 CLOCK CONTROL 1 CONVST 2 CONTROL LOGIC CLK 14-BIT DAC SAR + COUNTER SERIAL INTERFACE 4 5 6 8 15 SSTRB SCLK SDATA DGND VSS FEATURES: DESCRIPTION: • 14-bit resolution and accuracy • Total dose hardness: - > 100 krad (Si), depending upon space mission • Single event effects: - SEL > 104 MeV/mg/cm2 - SEUTH = 1.4 MeV/mg/cm2 - SEUSat = 1E-3 cm2/Device • Package: - 16 pin RAD-PAK® flat package - 16 pin RAD-PAK® dual-in-line package • Fast Conversion Times: 10 µ s • Low 50 mW typical power consumption • High speed LC2MOS technology - Analog input range of ±3V - 83 KSPS throughput rate - Operates with +5V/-5V power supplies - 80 dB SNR at 10 kHz input frequency - 2 s complement coding - Serial output Maxwell Technologies’ 7872 high-speed 14-bit ADC microcircuit features a greater than 100 krad (Si) total dose tolerance; depending upon orbit. The 7872 consists of a track/hold amplifier, successive-approximation ADC, 3V buried Zener reference and versatile interface logic. It features a self-contained, laser- trimmed internal clock, so no external clock timing components are required. For minimum noise possible, the onchip clock may be overridden to synchronize the device operation to the digital system. The 7872 is a serial output device. It is capable of interfacing to all modern microprocessors and digital signal processors. The 7872 operates from ±5V power supplies, accepts bipolar input signals of ±3V and is able to convert full power signals up to 41.5 kHz. It is also fully specified for dynamic performance parameters including distortion and signal-to-noise ratio. Maxwell Technologies' patented RAD-PAK® packaging technology incorporates radiation shielding in the microcircuit package. It eliminates the need for box shielding while providing the required radiation shielding for a lifetime in orbit or space mission. In a GEO orbit, RAD-PAK provides greater than 100 krad (Si) radiation dose tolerance. This product is available with screening up to Class S. 5.21.02 Rev 4 (858) 503-3300 - Fax: (858) 503-3301 - www.maxwell.com All data sheets are subject to change without notice 1 ©2001 Maxwell Technologies All rights reserved. Memory Logic Diagram 7872 14-Bit A/D Converter TABLE 1. 7872 PIN DESCRIPTION PIN SIGNAL DESCRIPTION 1 CONTROL Control Function 2 CONVST Convert Start 3 CLK 4 SSTRB Serial Strobe 5 SCLK Serial Clock 6 SDATA Serial Data 7 NC Non Connect 8 DGND Digital Ground 9 VDD Positive Supply 10 NC No Connect 11 CREF Reference Capacitor 12 AGND Analog Ground 13 REFOUT Voltage Reference Output 14 VIN Analog Input 15 VSS Negative Supply 16 VDD Positive Supply Clock Input Memory TABLE 2. 7872 ABSOLUTE MAXIMUM RATINGS PARAMETER SYMBOL MIN MAX UNIT Positive Supply Voltage; Relative to GND VDD -0.3 7.0 V Negative Supply Voltage; Relative to GND VSS 0.3 7.0 V AGND to DGND; Relative to GND -- -0.3 VDD +0.3 V REFOUT, CREF to AGND -- 0 VDD V VIN to AGND -- VSS -0.3 VDD +0.3 V Digital Input Voltage VIN -0.3 VDD +0.3 V VOUT -0.3 V ΘJC VDD +0.3 -- 2.44 °C/W Storage Temperature Range TS -65 150 °C Operating Temperature Range TA -55 125 °C Digital Output Voltage Thermal Impedance 5.21.02 Rev 4 All data sheets are subject to change without notice 2 ©2001 Maxwell Technologies All rights reserved. 7872 14-Bit A/D Converter TABLE 3. 7872 DC ELECTRICAL CHARACTERISTICS FOR DYNAMIC PERFORMANCE 1 (VDD = 5 V ± 5%, VSS = -5 V ± 5%, AGND = DGND = 0 V, fCLK = 2 MHZ EXTERNAL, fSAMPLE = 83 KHZ, -55 TO 125 ° C UNLESS OTHERWISE SPECIFIED) PARAMETER SYMBOL SUBGROUPS MIN TYP MAX UNIT Signal to Noise Ratio VIN = 10kHz Sine Wave, TMIN to TMAX; SNR is typically 82dB for VIN < 41.5kHz 2 SNR 4, 5, 6 79 -- -- dB Total Harmonic Distortion VIN = 10kHz Sine Wave THD 4, 5, 6 -- -86 -- dB -- 4, 5, 6 -- -86 -- dB IMD 4, 5, 6 --- -86 -86 --- -- -- 2 µs Peak Harmonic or Spurious Noise Intermodulation Distortion Second Order Terms: fa = 9 kHz, fb = 9.5 kHz, fSAMPLE = 50 kHz Third Order Terms: fa = 9 kHz, fb = 9.5 kHz, fSAMPLE= 50 kHz Track/Hold Acquisition Time -- 4, 5, 6 dB Memory 1. VIN = ± 3 V. Guaranteed by design. 2. SNR calculation includes distortion and noise components. TABLE 4. 7872 DC ELECTRICAL CHARACTERISTICS FOR ACCURACY (VDD = 5V ±5%, VSS = -5 V ± 5%, TA = -55 TO 125 °C UNLESS OTHERWISE SPECIFIED) PARAMETER SYMBOL SUGROUPS MIN TYP MAX UNIT Resolution -- 1, 2, 3 14 -- -- Bits Resolution for Which No Missing Codes are Guaranteed -- 1, 2, 3 14 -- -- Bits Integral Nonlinearity @ 25 ° C -- 1, 2, 3 -- ±1 -- LSB Integral Nonlinearity TMIN to TMAX -- 1, 2, 3 -- -- ±2 LSB Bipolar Zero Error -- 1, 2, 3 -- -- ±12 LSB Positive Gain Error 1 -- 1, 2, 3 -- -- ±12 LSB Negative Gain Error 1 -- 1, 2, 3 -- -- ±12 LSB 1. Measured with respect to internal reference. TABLE 5. 7872 DC ELECTRICAL CHARACTERISTICS FOR ANALOG INPUT (VDD = 5V ±5%, VSS = -5 V ± 5%, TA = -55 TO 125 °C UNLESS OTHERWISE SPECIFIED) PARAMETER SYMBOL SUBGROUPS MIN MAX UNITS Input Voltage Range -- 1, 2, 3 -3 3 V Input Current -- 1, 2, 3 -500 500 µA 5.21.02 Rev 4 All data sheets are subject to change without notice 3 ©2001 Maxwell Technologies All rights reserved. 7872 14-Bit A/D Converter TABLE 6. 7872 DC ELECTRICAL CHARACTERISTICS FOR REFERENCE OUTPUT (VDD = 5V ±5%, VSS = -5 V ± 5%, TA = -55 TO 125 °C UNLESS OTHERWISE SPECIFIED) PARAMETER SYMBOL SUGGROUPS MIN MAX UNIT REFOUT @ +25 ° C -- 1, 2, 3 2.99 3.01 V REFOUT TMIN to TMAX -- 1, 2, 3 2.98 3.02 V REFOUT Tempco: Typically 35ppm -- 1, 2, 3 -- ±40 ppm/oC Reference Load Sensitivity (DREFOUT/DI) Reference Load Current Change (0-300 µ A); Reference Load Should Not Be Changed During Conversion -- 1, 2, 3 -- 1.2 mV TABLE 7. 7872 DC ELECTRICAL CHARACTERISTICS FOR LOGIC INPUTS (VDD = 5V ±5%, VSS = -5 V ± 5%, TA = -55 TO 125 °C UNLESS OTHERWISE SPECIFIED) PARAMETER SUGGROUPS MIN MAX UNIT Input High Voltage: VDD 5 V ± 5% VINH 1, 2, 3 2.4 -- V Input Low Voltage: VDD 5 V ± 5% VINL 1, 2, 3 -- 0.8 V Input Current: VIN = 0 V to VDD IIN 1, 2, 3 -10 10 µA Input Current: (14/8/CLK input only) VIN = VSS to VDD -- 1, 2, 3 -10 10 µA CIN 1, 2, 3 -- 10 pF Input Capacitance 1 Memory SYMBOL 1. Not tested. TABLE 8. 7872 DC ELECTRICAL CHARACTERISTICS FOR LOGIC OUTPUTS (VDD = 5V ±5%, VSS = -5 V ± 5%, TA = -55 TO 125 °C UNLESS OTHERWISE SPECIFIED) PARAMETER SYMBOL SUBGROUPS MIN MAX UNIT Output High Voltage ISOURCE = 40 µ A VOH 1, 2, 3 4.0 -- V Output Low Voltage ISINK = 1.6 mA VOL 1, 2, 3 -- 0.4 V Floating-State Leakage Current -- 1, 2, 3 -- 10 µA Floating-State Output Capacitance 1 -- 1, 2, 3 -- 15 pF 1. Not tested. TABLE 9. 7872 DC ELECTRICAL CHARACTERISTICS FOR CONVERSION TIME (VDD = 5V ±5%, VSS = -5 V ± 5%, TA = -55 TO 125 °C UNLESS OTHERWISE SPECIFIED) PARAMETER SYMBOL SUBGROUPS MIN MAX UNIT External Clock -- 1, 2, 3 -- 10 µs Internal Clock: Nominal Value = 2 MHz -- 1, 2, 3 -- 11 µs 5.21.02 Rev 4 All data sheets are subject to change without notice 4 ©2001 Maxwell Technologies All rights reserved. 7872 14-Bit A/D Converter TABLE 10. 7872 DC ELECTRICAL CHARACTERISTICS FOR POWER REQUIREMENTS (VDD = 5V ±5%, VSS = -5 V ± 5%, TA = -55 TO 125 °C UNLESS OTHERWISE SPECIFIED) PARAMETER SYMBOL CONDITIONS REQUIREMENTS UNITS Positive Supply Voltage VDD 5% for Specified Performance 5 V Negative Supply Voltage VSS 5% for Specified Performance -5 V Positive Supply Current IDD Typically 6mA 13 mA max Negative Supply Current ISS Typically 4mA 6 mA max Power Dissipation PD Typically 50mW 95 mW max TABLE 11. 7872 TIMING CHARACTERISTICS 1,2 (VDD = 5V ±5%, VSS = -5 V ± 5%, TA = -55 TO 125 °C UNLESS OTHERWISE SPECIFIED) PARAMETER/CONDITION SUBGROUPS MIN MAX UNITS CONVST Pulse Width t1 9, 10, 11 50 -- ns SSTRB to SCLK Falling Edge Setup Time t10 9, 10, 11 100 -- ns SCLK Cycle Time 3 t11 9, 10, 11 440 -- ns t12 9, 10, 11 -- 155 ns SCLD Rising Edge to SSTRB t13 9, 10, 11 20 150 ns Bus Relinquish Time After SCLK t14 9, 10, 11 4 100 ns SCLK to Valid Data Delay: CL = 35 pF 4 Memory SYMBOL 1. All input signals are specified with tr = tr = 5 ns (10% to 90% of 5 V) and timed from a voltage level of 1.6 V. 2. Serial timing is measured with a 4.7 kΩ pull-up resistor on SDATA and SSTRB and a 2 kΩ pull-up resistor on SCLK. The capacitance on all three outputs is 35 pF. 3. SCLK mark/space ration (measured from a voltage level of 1.6 V) is 40/60 to 60/40. 4. SDATA will drive higher capacitive loads, but this will add to t12 since it increases the external RC time constant (4.7kΩ/CL) and hence, the time to reach 2.4 V. 5.21.02 Rev 4 All data sheets are subject to change without notice 5 ©2001 Maxwell Technologies All rights reserved. 7872 14-Bit A/D Converter FIGURE 1. MODE 1 TIMING DIAGRAM SERIAL t1 TRACK HOLD GOES INTO HOLD CONVST SSTRB 1 t10 t11 t13 SCLK2 t12 LEADING ZEROS SDATA t14 DB13 DB12 DB11 DB10 DB0 2. External 2 kΩ pull-up resistor continuos SCLK (DASHED LINE) when 14/8/CLK (CONTROL) = -5 V; noncontinuous when 14/ 8/CLK (CONTROL) = 0 V. FIGURE 2. MODE 2 TIMING DIAGRAM, SERIAL READ HBEN1 SSTRB 2 t10 t11 t13 SCLK3 t12 t14 SDATA2 1. Times t15, t18, t19 and t20 are the same for a high byte read as for a low byte read. 2. External 4.7 kΩ pull-up resistor. 3. Continuos SCLK (DASHED LINE) when 14/8/CLK (CONTROL) = -5 V; noncontinuous when 14/8/CLK (CONTROL) = 0 V. External 2 kΩ pull-up resistor. 5.21.02 Rev 4 All data sheets are subject to change without notice 6 ©2001 Maxwell Technologies All rights reserved. Memory 1. External 4.7 kΩ pull-up resistor. 7872 14-Bit A/D Converter FIGURE 3. LOAD CIRCUIT FOR ACCESS TIME 1.6mA IOL TO OUTPUT PIN +2.1V CL 50pF IOH 200uA Memory FIGURE 4. LOAD CIRCUIT FOR OUTPUT FLOAT DELAY IOL 1.6mA TO OUTPUT PIN +2.1V CL 50pF IOH 200uA 5.21.02 Rev 4 All data sheets are subject to change without notice 7 ©2001 Maxwell Technologies All rights reserved. 7872 14-Bit A/D Converter Memory 16 PIN RAD-PAK® FLAT PACKAGE DIMENSION SYMBOL MIN NOM MAX A 0.116 0.130 0.143 b 0.015 0.017 0.022 c 0.004 0.005 0.009 D -- 0.415 0.440 E 0.245 0.280 0.285 E1 -- -- 0.315 E2 0.130 0.156 -- E3 0.030 0.062 -- e 0.050 BSC L 0.325 0.335 0.345 Q 0.020 0.033 0.045 S1 0.005 0.024 -- N 16 F16-01 Note: All dimensions in inches 5.21.02 Rev 4 All data sheets are subject to change without notice 8 ©2001 Maxwell Technologies All rights reserved. 7872 14-Bit A/D Converter E N/2 D S2 A c Q L eA/2 e b2 Memory S1 eA b 16 PIN RAD-PAK® DUAL IN LINE PACKAGE DIMENSION SYMBOL MIN NOM MAX A -- 0.157 0.200 b 0.014 0.018 0.026 b2 0.045 0.047 0.065 c 0.008 0.010 0.018 D -- 0.800 0.840 E 0.220 0.295 0.310 eA 0.300 BSC eA/2 0.150 BSC e 0.100 BSC L 0.135 0.145 0.155 Q 0.000 0.002 0.060 S1 0.005 0.027 -- S2 0.005 -- -- N 16 D16-01 Note: All dimensions in inches 5.21.02 Rev 4 All data sheets are subject to change without notice 9 ©2001 Maxwell Technologies All rights reserved. 7872 14-Bit A/D Converter Important Notice: These data sheets are created using the chip manufacturer’s published specifications. Maxwell Technologies verifies functionality by testing key parameters either by 100% testing, sample testing or characterization. The specifications presented within these data sheets represent the latest and most accurate information available to date. However, these specifications are subject to change without notice and Maxwell Technologies assumes no responsibility for the use of this information. Maxwell Technologies’ products are not authorized for use as critical components in life support devices or systems without express written approval from Maxwell Technologies. Any claim against Maxwell Technologies must be made within 90 days from the date of shipment from Maxwell Technologies. Maxwell Technologies’ liability shall be limited to replacement of defective parts. Memory 5.21.02 Rev 4 All data sheets are subject to change without notice 10 ©2001 Maxwell Technologies All rights reserved. 7872 14-Bit A/D Converter Product Ordering Options Model Number 7872 RP X X Option Details Feature Monolithic S = Maxwell Class S B = Maxwell Class B I = Industrial (testing @ -55°C, +25°C, +125°C) E = Engineering (testing @ +25°C) Package D = Dual In-line Package (DIP) F = Flat Pack Radiation Feature RP = RAD-PAK® package Base Product Nomenclature 14-Bit A/D Converter 5.21.02 Rev 4 All data sheets are subject to change without notice Memory Screening Flow 11 ©2001 Maxwell Technologies All rights reserved.