SC7107

SC7106/7107 31/2 DIGITS, LCD/LED DISPLAY , A/D CONVERTERS FOR DMM DESCRIPTION The SC7106 and SC7107 are high performance, low power, 3 1/2 digit A/D converters. Included are seven segment decoders, display drivers, a reference, and a clock. The SC7106 is designed to int erface with a liquid crystal display (LCD) and includes a multiplexed backplane drive; the SC7107 will directly drive an instrument size light emitting diode (LED) display. The SC7106 and SC7107 bring together a combination of high accuracy, versatility, and true economy. It features auto-zero to less than 10µV, zero drift of less than 1µV/°C, input bias current of 10pA (Max), and rollover error of less than one count. True differential inputs and reference are useful in all systems, but give the designer an uncommon advantage when measuring load cells, strain gauges and other bridge type transducers. Finally, the true economy of single power supply operation (SC7106), enables a high performance panel meter to be built with the addition of only 10 passive components and a display. QFP-44-10 x10-0.8 DIP-40-600-2.54 FEATURES * Guaranteed zero reading for 0V input on all scales * True polarity at zero for precise null detection * Low power dissipation-typically ORDERING INFORMATION Part No. SC7106CPL SC7106RCPL SC7106 SC7107CPL SC7107RCPL SC7107 Temp. Range(°C) 0~70 0~70 0~70 0~70 0~70 0~70 Package DIP-40-600-2.54 DIP-40-600-2.54 QFP-44-10X10-0.8 DIP-40-600-2.54 DIP-40-600-2.54 QFP-44-10X10-0.8 less than 10mW * True differential input and reference, direct display driveLCD SC7106, LED SC7107 * Low noise (less than 15µVp-p) * On chip clock and reference * 1pA typical input current * No additional active circuits required NOTE: “ indicates device with reversed leads for mounting to PC board R” underside. HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.02.27 Page 1 of 22 SC7106/7107 BLOCK DIAGRAM ABSOLUTE MAXIMUM RATING Characteristics SC7106 Supply Voltage SC7107 SC7107 Analog Input Voltage(Either Input) (Note 1) Reference Input Voltage(Either Input) Clock Input SC7106 SC7107 Topr Tstg θJA Symbol V+ ~ VV+ ~ GND V- ~ GND Value 15 6 -9 V+ ~ VV+ ~ VTEST to V+ GND to V+ 0 ~ +70 -65 ~ 150 50 150 °C °C °C/W °C V Unit Operating Temperature Storage Temperature Thermal resistance(typical) (Note 2) Maximum Junction Temperature NOTE: 1. Input voltages may exceed the supply voltages provided the input current is limited to ±100µA. 2. θJA is measured with the component mounted on an evaluation PC board in free air. 3. Not tested, guaranteed by design. 4. Back plane drive is in phase with segment drive for "off" segment, 180 degrees out of phase for "on" segment. Frequency is 20 times conversion rate. Average DC component is less than 50mV. HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.02.27 Page 2 of 22 SC7106/7107 ELECTRICAL CHARACTERISTICS(Unless otherwise noted, specificatons apply to both the SC7106 and SC7107 at Tamb=25°C, Fclock=48kHz, SC7106 is tested in the circuit of Figure 1. SC7107 is tested in the circuit of Figure 2.) Characteristics SYSTEM PERFORMANCE Zero Input Reading Ratiometric Reading VIN=0.0V, Full Scale=200mV VIN=VREF, VREF=100mV -VIN=+VIN ≈ 200mV Rollover Error Difference In Reading For Equal Positive And Negative Inputs Near Full Scale Full Scale =200mV Or Full Scale =2V Linearity Maximum Deviation From Best Straight Line Fit (Note 3) Common Mode Rejection Ratio Noise Leakage Current Input Zero Reading Drift Scale Factor Temperature Coefficient End Power Supply Character V+ Supply Current End Power Supply Character VSupply Current COMMON Pin Analog Common Voltage Temperature Coefficient Of Analog Common DISPLAY DRIVER (SC7106 ONLY) Peak-To-Peak Segment Drive Voltage Peak-To-Peak Backplane Drive Voltage DISPLAY DRIVER (SC7107 ONLY) Segment Sinking Current (Except Pins 19 And 20) Pin 19 Only Pin 20 Only V+=5V, Segment Voltage=3V 5 10 4 8 16 7 ---mA mA mA V+ To V-=9V(Note 4) 4 5.5 6 V VCM=1V,VIN=0V,Full Scale=200mV (Note 3) VIN=0V,Full Scale=200mV,(Peak-To-Peak Value Not Exceeded 95% of Time) VIN=0(Note 3) VIN=0, 0°C To 70°C(Note 3) VIN=199mV, 0°C TO 70°C (Ext.Ref.0ppm/°C) (Note 3) VIN=0(Does Not Include LED Current For SC7107) SC7107 Only 25kΩ Between Common And Positive Supply (With Respect To V+ Supply) 25kΩ Between Common And Positive Supply (With Respect To V+ Supply) -------2.4 -50 15 1 0.2 1 1.0 0.6 3.0 80 --10 1 5 1.8 1.8 3.2 -µV/V µV pA µV/°C ppm/°C mA mA V ppm/°C -±0.2 ±1 Counts -±0.2 ±1 Counts -000.0 999 ±000. +000. Digital 0 999/ 1000 0 1000 Reading Digital Reading Test Conditions Min. Typ. Max. Unit HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn REV:1.2 2006.02.27 Page 3 of 22 SC7106/7107 PIN CONFIGURATION BP/GND POL AB4 G2 G3 C3 LB A3 E3 INTEN HOLD TEST OSC3 OSC2 OSC1 D1 C1 HANGZHOU SILAN MICROELECTRONICS CO.,LTD Http: www.silan.com.cn DEEN V+ B1 B3 F3 REV:1.2 2006.02.27 Page 4 of 22 SC7106/7107 DESIGN INFORMATION SUMMARY SHEET OSCILLATOR FREQUENCY OSCILLATOR PERIOD INTEGRATION CLOCK FREQUENCY INTEGRATION PERIOD 60/50Hz REJECTION CRITERION OPTIMUM INTEGRATION CURRENT FULL SCALE ANALOG INPUT VOLTAGE INTEGRATE RESISTOR INTEGRATE CAPACITOR INTEGRATOR OUTPUT VOLTAGE SWING VINT MAXIMUM SWING DISPLAY COUNT CONVERSION CYCLE COMMON MODE INPUT VOLTAGE AUTO-ZERO CAPACITOR REFERENCE CAPACITOR VCOM VCOM ≈ V+−2.8V SC7106 POWER SUPPLY: SINGLE 9V SC7106 DISPLAY: LCD SC7107 POWER SUPPLY:DUAL±5.0V SC7107 DISPLAY: LED fosc=0.45/RC; Cosc>50pF; Rosc>50kΩ; fosc(Typ)=48kHz tosc=RC/0.45 Fclock=fosc/4 tINT=1000x(4/fosc) tINT/ t60Hz or tINT/ t50Hz=Integer IINT=4µA VINFS(Typ)=200mV or 2V RINT=VINFS/IINT CINT=(tINT) (IINT)/VINT VINT=(tINT) (IINT)/CINT (V-+0.5V)