ES51981

ES51981 3 1/2 AUTO DMM Features • 2000 count display • Full automatic measurement *Voltage measurement *Current measurement *Resistor measurement • Range change function • Data hold function • Diode measurement • ADP mode with external reference voltage • Serial data output (RS232 format) • Auto power off (10 mins) and re-power on • Low battery detect (3V and 9V) • 3V DC power supply • Back light function Description ES51981 is an integrated analog-to-digital Converter(ADC) with 2000 counts LCD display ,automatic range selection, and 3V DC power supply. Automatic range selection is provided for voltage(AC/DC) measurement, resistor measurement and current measurement. Expensive and bulky mechanical range switches are not required. Other features include data holding, diode measurement, temperature measurement, continuity checking, low battery detection, auto- power off, re-power on, and RS232 data output. Application Digital Multimeter 1 08/09/09 ES51981 3 1/2 AUTO DMM Pin Assignment HOLD RANGE SLACDC KEY FC5 FC4 FC3 FC2 FC1 NC C+ CNC SDO LBAT9 VVDGND AGND AGND 100 90 80 NC V+ V+ NC CL+ CLCIL CAZL BUFL IVSH IVSL OVX OVH OVSG NC OR1 VR5 VR4 VR3 VR2 TEST5 ACVL ACVH NC ADI NC ADO NC VRH VR 1 10 70 20 60 30 40 50 NC BKOUT NC XTAL NC OSC1 OSC2 NC BUZOUT BUZIN NC ANNUNC BP1 BP2 BP3 BP4 SEG01 SEG02 SEG03 SEG04 SEG05 SEG06 SEG05 SEG07 SEG08 SEG09 SEG10 SEG11 SEG12 NC NC SEG13 SEG14 NC SEG15 BKLIT RS232 NC NC SLEEP NC NC NC NC VBAR NC VR1 SGND ADP VAVA+ 2 08/09/09 ES51981 3 1/2 AUTO DMM Pin Description Pin No 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 Symbol NC V+ V+ NC CL+ CLCIL CAZL BUFL IVSH IVSL OVX OVH OVSG NC OR1 VR5 VR4 VR3 VR2 TEST 5 ACVL ACVH NC ADI NC ADO NC VRH VR VA+ VAADP SGND VR1 NC VBAR NC NC NC NC SLEEP NC NC RS232 BKLIT SEG15 NC Type P P IO IO O O O I I I I I O O O O O I/O O O I O O I I Description Positive supply voltage, output of on-chip DC-DC converter. Positive supply voltage, output of on-chip DC-DC converter. High resolution positive connection for reference capacitor. High resolution negative connection for reference capacitor. High resolution integrator output. Connected to integral capacitor High resolution auto-zero capacitor connection. Integral resistor connection for high resolution buffer output High current measurement input. Low current measurement input Input high voltage for resistance measurement Output connection for resistance measurement Sense low voltage for resistance measurement Reference resistor connection for 200.0Ω range Voltage measurement ÷10000 attenuator(2000V) Voltage measurement ÷1000 attenuator(200.0V) Voltage measurement ÷100 attenuator(20.00V) Voltage measurement ÷10 attenuator(2.000V) Test pin Negative output of AC to DC converter Positive output of AC to DC converter. Negative input of internal AC to DC Opamp. Output of internal AC to DC Opamp. Output of band-gap voltage reference .Typically –1.2V Reference input voltage connection. Typically –100mV For ADP. Deintegrating voltage positive input. The input should be higher than VA-. For ADP. Deintegrating voltage negative input. The input should be lower than VA+. ADP input Signal Ground Measurement input Decimal point control for temperature measurement in ADP mode. I G I I O I I O Asserts low in the sleep mode. See page 8, function description Pulse low to enable serial data output. Back light function. Pulse low to set BKOUT pin output LCD segment line 15 3 08/09/09 ES51981 3 1/2 AUTO DMM …continued from previous page 49~50 SEG14~SEG1 O 3 51~52 NC 53~64 SEG12~SEG0 O 1 65 BP4 O 66 BP3 O 67 BP2 O 68 BP1 O 69 ANNUNC O LCD segment line 14~13 LCD segment line 12~01 LCD backplane 4 LCD backplane 3 LCD backplane 2 LCD backplane 1 Square wave output at the backplane frequency, synchronized to BP1. ANNUNC can be used to control display annunciator. Connect an LCD segment to ANNUNC to turn it on; connect an LCD segment to its backplane to turn it off. Enables the buzzer. Low active. Outputs an 2KHz audio frequency signal for driving piezoelectric buzzer when BUZIN is low. Crystal oscillator output connection Crystal oscillator input connection The chip uses internal RC oscillator if pin is connected to V-, and uses external crystal oscillator if this pin is floating or connected to DGND If BKLIT function is enabled, this pin will change from –3V to +3V for 60 sec, once press BKLIT pin again within 60 sec, this pin will change back to –3V. Pulse low to enable HOLD mode. Pulse low to enable manual mode and manual range selection. Select AC/DC initial state. This pin is pull low Pulse low to change mode. In ADP mode, if this pin is connected to V-, the buzzer output will be off when the ADP input overflows. Switch 5 for function selection. Switch 4 for function selection. Switch 3 for function selection. Switch 2 for function selection. Switch 1 for function selection. Positive capacitor connection for on-chip DC-DC converter. Negative capacitor connection for on-chip DC-DC converter. RS232 compliant serial data output. Low battery configuration. If 3V battery is used, connect it to AGND. The default low-battery threshold voltage is –2.3V. If 9V battery is used, the low battery annunciator is displayed when the voltage of this pin is less than VRH (-1.2V) Negative supply voltage. Connecting to battery negative terminal. Negative supply voltage. Connecting to battery negative terminal. Digital ground, connected to battery positive terminal. Analog ground. Analog ground. 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 NC BUZIN BUZOUT NC OSC2 OSC1 NC XTAL NC BKOUT NC HOLD RANGE SLACDC KEY FC5 FC4 FC3 FC2 FC1 NC C+ CNC SDO LBAT9 I O O I I O I I I I I I I I I O O O I 96 97 98 99 100 VVDGND AGND AGND P P G G G 4 08/09/09 ES51981 3 1/2 AUTO DMM Absolute Maximum Ratings Characteristic Supply Voltage (V- to AGND) Analog Input Voltage V+ AGND/DGND Digital Input Power Dissipation. Flat Package Operating Temperature Storage Temperature Rating -4V V- -0.6 to V+ +0.6 V+ ≥ (AGND/DGND+0.5V) AGND/DGND ≥ (V- -0.5V) V- -0.6 to DGND +0.6 500mW 0℃ to 70℃ -25℃ to 125℃ Electrical Characteristics TA=25℃, V- = -3V Parameter Power supply Operating supply current In DCV mode Voltage roll-over error Voltage nonlinearity Input Leakage Low battery flag voltage Zero input reading Reference voltage and open circuit Voltage for 200Ω measurement Peak to peak backplane Drive voltage Counter time base period Open circuit voltage for Ω Measurement (except 200Ω) Symbol Test Condition VIDD Normal operation In sleep mode ISS REV 10MΩ input resistor Best case straight NLV line V- to AGND 10MΩ input resistor 100KΩ resistor between VRH and AGND -3.5V≤ V ≤-2.2V fOSC = 4MHZ Ω and Continuity Mode Between V- pin and HOLD, RANGE, KEY, FC1, FC2, FC3, FC4, FC5, XTAL, BKLIT Between V- pin and RS232 Between GND Pin and SLACDC ±1% ±5% 100KΩ resister Between VRH 0℃