ES51982 3 1/2 CAP AUTO DMM Features Description • 2000 count display ES51982 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, resistance measurement, current measurement, capacitance measurement, frequency counter. Expensive and bulky mechanical range switches are not required. Other features include data holding, diode measurement, temperature measurement, continuity checking, low battery detection, autopower off, re-power on, and RS232 data output. • Full automatic measurement *Voltage measurement *Current measurement *Resistance measurement • Capacitance measurement (Auto range: 2n to 2mF) (Taiwan patent no: 453443) • 20MHz Frequency counter • Range change function • Data hold function Application • Diode measurement Digital Multimeter • 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 1 11/01/05 ES51982 3 1/2 CAP AUTO DMM Pin Assignment HOLD RANGE SLACDC KEY FC5 FC4 FC3 FC2 FC1 NC C+ CNC SDO LBAT9 VVDGND AGND AGND 100 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 90 80 1 10 70 20 30 60 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 SEG15 SEG16 BKLIT RS232 NC FREQ SLEEP CA+ CAR1K R9K VBAR NC VR1 SGND ADP VAVA+ 2 11/01/05 ES51982 3 1/2 CAP 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 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+ Type Description P P Positive supply voltage, output of on-chip DC-DC converter. Positive supply voltage, output of on-chip DC-DC converter. IO IO O O O I I I I I 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 O O O O O I/O O O 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. I Negative input of internal AC to DC Opamp. O Output of internal AC to DC Opamp. O I I 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 32 VA- 33 34 35 36 37 ADP SGND VR1 NC VBAR I G I 38 39 40 41 42 43 44 45 46 47~50 R9K R1K CACA+ SLEEP FREQ NC RS232 BKLIT O O IO IO O I In capacitance mode, a compensation capacitance is connected In temperature mode, it is used to control decimal point. See page Connect to a 9KΩ resister for capacitor measurement. Connect to a 1KΩ resister for capacitor measurement. Negative auto-zero capacitor connection for capacitor measurement Positive auto-zero capacitor connection for capacitor measurement Asserts low in the sleep mode. See page 9, function description Frequency counter input, offset V-/2 internally by the chip. I I O Pulse low to enable serial data output. Back light function. Pulse low to set BKOUT pin output LCD segment line 16~13 SEG16~SEG13 I 3 11/01/05 ES51982 3 1/2 CAP AUTO DMM …continued from previous page NC 51 NC 52 53~64 SEG12~SEG01 O 65 BP4 O 66 BP3 O 67 BP2 O 68 BP1 O 69 ANNUNC O 70 71 72 NC BUZIN BUZOUT 73 74 75 76 77 NC OSC2 OSC1 NC XTAL 78 79 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. I O Enables the buzzer. Low active. Outputs an 2KHz audio frequency signal for driving piezoelectric buzzer when BUZIN is low. O I Crystal oscillator output connection Crystal oscillator input connection I NC BKOUT 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 O 80 81 82 83 84 NC HOLD RANGE SLACDC KEY 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. I I I I 85 86 87 88 89 90 91 92 93 94 95 FC5 FC4 FC3 FC2 FC1 NC C+ CNC SDO LBAT9 I I I I I 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. O O Positive capacitor connection for on-chip DC-DC converter. Negative capacitor connection for on-chip DC-DC converter. O I 96 97 98 99 100 VVDGND AGND AGND 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. P P G G G 4 11/01/05 ES51982 3 1/2 CAP 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 Symbol Test Condition VIDD Normal operation ISS In sleep mode Min. -3.5 — — Typ. -3.0 0.9 2.5 Max -2.2 1.4 5 Units V mA µA Voltage roll-over error REV 10MΩ input resistance — — ±0.1 %F.S Voltage nonlinearity NLV Best case straight line — — ±0.1 %F.S -10 -2.5 -000 1 -2.3 000 10 -2.1 +000 PA V counts -1.3 -1.2 -1.1 V 3.00 3.2 3.40 V — 1 — sec -0.54 -0.47 -0.4 V — 1.2 — — 11 — 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) Internal pull-high to 0V current Internal pull-low to Vcurrent AC frequency response at 2.000V range VREF V- to AGND 10MΩ input resistance 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% 5 1.5 — — 40-400 40-2000 µA µA — — HZ 11/01/05 ES51982 3 1/2 CAP AUTO DMM Reference voltage temperature Coefficient TCRF 100KΩ resister Between VRH 0℃<TA<70℃ 2nF range Capacitance Measurement accuracy 20nF – 2µF 2µF~2mF — 50 — ppm/℃ -1.5 -2 — — 1.5 2 %F.S counts -0.8 -2 -1.1* -2 — — — — 0.8 2 1.1* 2 %F.S counts %F.S counts *The accuracy of 20uF range is 1.5%F.S Function Description 1. Operating Modes 1.1 Voltage Measurement A reconfigurable voltage divider automatically provides a suitable range in voltage measurement mode. The following table summarizes the full scale ranges in each configuration. Configuration VR1 VR2 VR3 VR3 VR5 1. 2. Full Scale Range 200.0mV 2.000V 20.00V 200.0V 2000V Divider Ratio 1 1/10 1/100 1/1000 1/10000 Resister Connection R2 / (R1+R2) R3 / (R1+R3) R4 / (R1+R4) R5 / (R1+R5) 200.0mV range only exists in manual mode. In the 2000V range, if the digit number is larger than 1000V, LCD will display “OL”. The measurement of True RMS using ES636 If ES636 (or other true RMS-to-DC converter chip) is used for true RMS measurement, the suggested application circuit is shown in Figure 1. When ES636 is used for true RMS, make ADO and ADI pin short, keep TEST5 pin float, and connect ACVL pin to SGND. And connect OVSG pin to AGND through a switch in ACV mode. 6 11/01/05 ES51982 3 1/2 CAP AUTO DMM 2.2u + -Vs ES636 4.7u 1 2 3 4 5 6 7 14 13 12 11 10 150 9 8 +Vs 100 1K 10K 101K 1.111M OVSG OR1 VR5 VR4 VR3 VR2 ES51982 ACV TEST5 ACVL ACVH 10K +Vs 500K 2.2u + -Vs ADI ADO AGND 22k 1k Figure 1. the ture RMS measurement using ES636 1.2 Resistance Measurement A reconfigurable divider automatically provides a suitable full scale range in resistance measurement mode. The following table summarizes the full scale ranges and the reference resistors in each configuration. Configuration OR1 OR2 OR3 OR4 OR5 OR6 Full Scale Range 200.0Ω 2.000KΩ 20.00KΩ 200.0KΩ 2.000MΩ 20.00MΩ Divider Ratio R6 R5 R4 R1‖ R3 R1‖ R2 R1 7 Resister Connection 100Ω 1KΩ 10KΩ 100KΩ 1MΩ 10MΩ 11/01/05 ES51982 3 1/2 CAP AUTO DMM 1.3 Current measurement Current measurement has three modes. The following table summarizes the full scale range of each mode. Mode Automatic Mode 1 Automatic Mode 2 Automatic Mode 3 Manual Mode Range Selection µA mA A A Full Scale 200.0µA / 2000µA 20.00mA / 200.0mA 20.00A/2.000A 20.00A 1.4 Capacitance Measurement The following table summarizes the eight ranges of capacitance measurement mode. Configuration C1 C2 C3 C4 C5 C6 C7 Full Scale Range 2.000nF 20.00nF 200.0nF 2.000µF 20.00µF 200.0µF 2mF Resistance Ratio R1 R1‖ R2 R1‖ R3 R4 - Note: 1. In order to obtain an accurate reading, a capacitor must be discharged before measurement begins. The chip has a built-in discharge mode to automatically discharge the capacitor. In discharge mode, the LCD displays DS.C 2. Discharging through the chip is quite slow. We recommend the user to discharge the capacitor with some other apparatus. 1.5 Continuity Check Continuity check shares the same configuration with 200.0Ω manual resistance measurement mode, but with buzzer output to indicate continuity. The buzzer generates a 2KHz sound whenever the digit number less than 25Ω. Because the cycle time of measurement is only 50ms, the least significant digit will not display. 1.6 Diode Measurement Diode measurement mode shares the same configuration with 2.000V manual voltage measurement mode. If the test circuit is open or the voltage drop between the two ports of the device (diode) under test is larger than 2V, the LCD panel will show “OL”. The buzzer generates a 2KHz sound whenever the digit number is less than 0.25V. Because the cycle time of measurement is only 50ms, the least significant digit will not display. 8 11/01/05 ES51982 3 1/2 CAP AUTO DMM 1.7 Frequency counter The time base of the frequency counter is derived from an external crystal oscillator by 4000000 Fosc Tcounter = where fosc is the frequency of the crystal oscillator. Thus, the counter has a 1 second time base when a 4MHz oscillator is used. The frequency counter can select the proper range automatically or manually. Auto-range operation extends over five decades, from 2KHz to 20MHz The following table summarizes the full scale range of the frequency counter. Range FR1 FR2 FR3 FR4 FR5 Full Scale 2.000KHz 20.00KHz 200.0KHz 2.000MHz 20.00MHz 1.8 Auto power off ES51982 has a default auto power off function. If the meter idles for more than 10 minutes, the chip automatically turns the power off. When this happens, the state of the meter is saved. In order to disable auto power off function, power on the meter when any of the push function, except for HOLD, is pressed down. In addition, when RS232 output is active, the auto power-off function is also disabled. The APO sign on the LCD panel indicates whether the auto power-off is enabled or not. Note: Powering on the meter while pressing HOLD turns on all LCD segment until HOLD is pressed again. 1.9 Sleep The meter enters sleep mode after auto power off. The SLEEP pin asserts low (-3V) in the sleep mode, and asserts high (+3V, not 0V) after re-power on. 1.10 Re-power on After auto power-off, pushing any of the push function or changing the rotary mode can turn on the meter again. If the meter is re-powered on by changing the rotary mode, the saved state is cleared. If the meter is re-powered on by push functions, the chip restores the saved state and enters HOLD mode. The LCD displays the saved value. 9 11/01/05 ES51982 3 1/2 CAP AUTO DMM 2. Measurement Mode Switching Measurement mode depends on the logic level of FC1, FC2, FC3, FC4, FC5, and KEY. When FC5 is HIGH, the measurement modes are listed in the following table. SLACDC FC1 0 1 0 1 0 1 0 1 0 0 1 1 1 1 1 1 1 1 1 0 X 0 X 0 X 0 X 0 X 0 X 0 X 0 FC2 0 1 1 0 0 0 1 1 0 0 0 1 0 1 0 1 1 FC3 1 0 1 0 0 1 0 1 0 0 1 0 0 1 1 1 0 FC4 Mode Function of KEY 1 Voltage Measurement DCV(initial) ↔ACV 1 Current Measurement(µA) DCA(initial) ↔ACA 1 Current Measurement(mA) DCA(initial) ↔ ACA 1 Manual Current Measurement(A) DCA (initial) ↔ACA 0 Auto Current Measurement(A) DCA(initial) 1 Voltage Measurement ACV (initial) ↔DCV 1 Current Measurement(µA) ACA(initial) ↔DCA 1 Current Measurement(mA) ACA (initial) ↔DCA 1 Manual Current Measurement(A) ACA (initial) ↔DCA 0 Auto Current Measurement(A) ACA (initial) 1 Resistance Measurement Ω ↔ Continuity 1 Resistance Measurement Ω ↔ Diode 1 Continuity Check Continuity Diode 1 Resistance Measurement Ω ↔ Continuity ↔Diode 0 Frequency Measurement — 0 Capacitance Measurement — 0 — Temperature(℃) Ps. X means “don’t care” When FC5 is LOW, KEY is disable. The corresponding measurement modes are list below SLACDC FC1 FC2 FC3 FC4 Mode 0 1 0 1 1 AC Voltage Measurement 0 1 1 0 1 AC Current Measurement(µA) 0 1 1 1 1 AC Current Measurement(mA) 0 1 0 0 1 Manual AC Current Measurement(A) 0 0 0 0 0 Auto AC Current Measurement(A) 1 1 0 1 1 DC Voltage Measurement 1 1 1 0 1 DC Current Measurement(µA) 1 1 1 1 1 DC Current Measurement(mA) 1 1 0 0 1 Manual DC Current Measurement(A) 1 0 0 0 0 Auto DC Current Measurement(A) X 0 0 1 1 Resistance Measurement X 0 1 0 1 Resistance Measurement X 0 0 0 1 Continuity Check X 0 1 1 1 Diode Measurement X 0 0 1 0 Frequency Measurement X 0 1 1 0 Capacitance Measurement X 0 1 0 0 Temperature(℉) Ps. X means “don’t care” 10 11/01/05 ES51982 3 1/2 CAP AUTO DMM The other combinations of FC1, FC2, FC3, and FC4 are for ADP modes. In ADP modes , if FC5 is LOW, the minus sign on the LCD panel will not be displayed. And if KEY pin is floating, the buzzer beeps when the input signal is overflow. The ADP mode function is summarized below. FC1 1 1 1 1 FC2 1 1 0 0 FC3 1 0 0 1 FC4 0 0 0 0 Mode ADP0 ADP1 ADP2 ADP3 Note: Temperature measurement mode takes input signal from ADP pin. In temperature measurement mode, VBAR pin is used to control the right most digit point on the LCD panel. When VBAR is LOW, this digit point is displayed. 3. Push function 3.1 HOLD HOLD mode makes the meter stop updating the LCD panel. This mode can be nested in most of the special modes. Enabling HOLD function in automatic mode makes the meter switch to manual mode, but the full scale range remains the same. HOLD function can be cancelled by changing the measurement mode, pressing RANGE, or push HOLD again. 3.2 Range RANGE pin switches to and from automatic and manual mode, and while in manual mode, changes the full scale range. The following figure shows the state transition. Automatic Mode 1 push < 1 sec Manual Mode 1 push > 1 sec Range up 1 push < 1 sec 11 11/01/05 ES51982 3 1/2 CAP AUTO DMM Measurement Mode Auto Manual V(DC/AC) VR2 – VR5 VRi → VRi + 1, VR5 → VR1 µA(DC/AC) R1 – R2 R1 → R2, R2 → R1 mA R1－R2 R1 → R2 (AC/DC) R2 → R1 Auto A(DC/AC) R1 – R2 R1 → R2, R2 → R1 A(DC/AC) fixed Fixed ORi → Ω OR1- OR6 ORi + 1, OR6 → OR1 Capacitance C1-C7 Ci → Ci+1, C7 → C1 Continuity fixed fixed Diode Fixed fixed Frequency FR1 – FR5 FRi→ FRi+1 FR5→ FR1 Control Range Initial Range 200.0mV – 2000V 2.000V 200.0µA - 2000µA 200.0µA 20.00mA – 200.0mA 20.00mA 2.000A – 20.00A 2.000A 20.00A 20.00A 200.0Ω – 20.00MΩ 200.0Ω 2.000nF – 2.000mF 2.000nF 200.0Ω 2.000V 2.000KHz – 20.00MHz 200.0Ω 2.000V 2.000KHz Note: Pushing RANGE resets all existing special modes. 3.3 KEY See Section “Measurement Mode Switching” for the function of this pin. 4. Serial Data Output The serial data sent to SDO pin twice every A/D conversion cycle. The data format complies with JIS 7Bits transmission code with a baud rate of 19230. The host can use RS232 interface to read the data. A single data packet includes a start bit (always 0), 7 data bits, an odd parity check bit, and a stop bit (always 1). The high and low voltage levels correspond to DGND and V- respectively. SDO remains at 1 (high) when it is inactive. Hence the start bit (0) could be used as the triggering signal to begin the reading process. The following figure shows the data format of a single packet. The LSB is sent first and the MSB is sent last. single package 0V -3V 0 D0 ~D6 LSB p 1 P MSB One data block consists of 11 packets, or 110 bits. The following figure shows the format of a data block. The range packet indicates the full scale range of the meter. 12 11/01/05 ES51982 3 1/2 CAP AUTO DMM Digit 3 through digit 0 are just the digits on the LCD panel. The function packet indicates the measurement mode of the meter. Status, option 1 and option 2 give the status of the meter. CR and LF are delimiters used to separate the blocks. all package p 1 0 0 range p 1 0 digit3 p 1 0 0 digit1 digit0 p 1 0 p 1 0 CR p 1 function p 1 option2 option1 status 0 digit2 p 1 0 p 1 0 0 p 1 p 1 LF The meter always outputs the current input value to the serial port in spite of HOLD mode. Each block is repeated twice in one conversion cycle. The detailed data format of each packet is listed below. 4.1 FUNCTUON This packet indicates the measurement mode of the meter. The following table summarizes the transmitted code for each mode. Note that the encoding of this packet is different from the encoding of FC1-FC4 switch. Code 0111011 0111101 0111111 0110000 0111001 0110011 0110101 0110001 0110010 0110110 0110100 0111110 0111100 0111000 0111010 Measurement Mode Voltage µA Current mA Current Auto A current Manual A Current Ω Continuity Diode Frequency Capacitor 1*Temperature ADP0 ADP1 ADP2 ADP3 13 11/01/05 ES51982 3 1/2 CAP AUTO DMM Note: 1*.The judge bit in the Status packet determines whether the unit is Celcius or Fahrenheit. 4.2 RANGE This packet indicates the full scale range of the meter. When the meter operates in continuity mode, diode mode, or current (A) mode, this packet is always 0110000 since the full scale range in these modes are fixed. The following table lists the code for each range in each measurement mode. Code 0110000 0110001 0110010 0110011 0110100 0110101 0110110 V 2.000V 20.00V 200.0V 2000V 200.0mV mA 20.00mA 200.0mA µA 200.0µA 2000µA Auto A 2.000 A 20.00 A Frequency Ω 200.0Ω 2.000KHz 2.000KΩ 20.00KHz 20.00KΩ 200.0KHz 200.0KΩ 2.000MHz 2.000MΩ 20.00MHz 20.00MΩ Capacitor 2.000nF 20.00nF 200.0nF 2.000µF 20.00µF 200.0µF 2.000mF 4.3 DIGIT 3 – DIGIT 0 Digit 3 is the most significant digit on the LCD panel, and digit 0 is the least significant digit. When the LCD panel shows OL, the serial port outputs 2000. Digit 0 1 2 3 4 5 6 7 8 9 Code 0110000 0110001 0110010 0110011 0110100 0110101 0110110 0110111 0111000 0111001 Because the cycle time of measurement for continuity/diode mode is only 50ms, the least significant digit may not be accurate. 4.4 STATUS The format of this shown below. The Judge field is meaningful only when the Function packet indicates Temperature mode. In Temperature mode, judge is 1 if the unit is ℃ and is 0 of the unit is ℉ . Sign field indicates whether the minus sign on the LCD panel is on or off. BATT field is one of battery low condition is true. OL indicates input overflow. 0 BIT 6 1 BIT 5 1 BIT 4 Judge BIT 3 14 Sign BIT 2 BATT BIT1 OL BIT 0 11/01/05 ES51982 3 1/2 CAP AUTO DMM 4.5 OPTION 1 This packet is not used. 0 BIT 6 1 BIT 5 1 BIT 4 HOLD BIT 3 0 BIT 2 0 BIT1 0 BIT 0 If Hold field is 1, Hold function is active. Hold function will not influence Digital 3~0 which is related to current measured value. 4.6 OPTION 2 This packet contains information on the operation mode of the meter. The format is shown below. The DC field indicates that the meter operates in DC measurement mode, either voltage or current. The AC field indicates that the meter operates in AC measurement mode, either voltage or current. The AUTO field is set to one if the meter operates in automatic mode, and is set to zero when the meter operates in manual mode. 0 BIT 6 1 BIT 5 1 BIT 4 DC BIT 3 AC BIT 2 AUTO BIT1 0 BIT 0 4.7 CR Carrage return. The transmitted code is 0001101. 4.8 LF Line feed. The transmitted code is 0001010. 5. Miscellaneous The conditions which the meter turns on the buzzer include: (1) Changing measurement mode generates one beep. (2) Pressing any of the push junctions generates one beep, if the function is valid. (3) Power on and re-power on generate one beep. (4) Input overflow in voltage and current mode generates one beep every 0.3 seconds (or 3.33 beeps per second.) (5) Continuity(diode) check generates a continuous 2KHz beep whenever the measurement is less then 25Ω(0.25V) (6) Auto power off generates a 2KHz beep which lasts for 1.5 seconds. The following figures shows the output waveform from the BUZOUT pin. 15 11/01/05 ES51982 3 1/2 CAP AUTO DMM 0.5 mS (a) Continuous 2KHz beep 0.15 sec 0.3 sec (b) 3.33 beep/sec 5.1 LCD Panel 1 BATT AUTO MANU DC AC HOLD ℃ ℉ n µ1 m1 F µ2 m2 V A APO M KΩ HZ RS232 BP1 BP2 BP3 BP4 SEG01 SEG02 SEG03 SEG04 SEG05 SEG06 SEG07 SEG08 BATT DC AUTO MANU A3 B3 HOLD A2 AC F4 A4 B4 F3 G3 F2 B2 APO G4 C4 E3 C3 E2 G2 — RS232 E4 D4 P3 D3 P2 D2 C2 SEG09 SEG10 F1 E1 P1 A1 G1 D1 SEG11 V B1 C1 K SEG12 A M HZ Ω SEG13 m2 × × × 16 SEG14 u2 × × × SEG15 n u1 m1 F SEG16 ℃ ℉ × × 11/01/05 ES51982 3 1/2 CAP AUTO DMM 5.2 LCD Backplane Waveform V- +3.1 VV- +3.1 VV- +3.1 VV- +3.1 VV- +3.1 V- 5.3 LCD display on condition LCD Annunciator V A Ω F Hz DC AC AUTO MANU HOLD m1 u1 n m2 u2 M K ℃ ℉ APO - Condition In voltage measurement mode, and diode measurement mode. In current measurement mode. In resistance measurement mode, and continuity mode. In capacitance measurement mode. In continuity check mode. In diode mode. In frequency mode. In DC voltage or DC current mode. In AC voltage or AC current mode. When automatic full scale range selection is enabled. In manual mode. When HOLD function is enabled. In capacitor measurement mode and the full scale range is in the order of mF. In capacitor measurement mode and the full scale range is in the order of uF. In capacitor measurement mode and the full scale range is in the order of nF. In voltage or current measurement mode and the full scale range is in the order of 10-3. In current measurement mode and the full scale range id in the order of uA. In resistance measurement mode and the full scale range is in the order of MΩ In resistance measurement mode and the full scale range is in the order of KΩ In temperature measurement mode and when the unit is ℃ In temperature measurement mode and when the unit is ℉ When auto power off function is enabled. In voltage or current measurement mode and when the input is negative. 17 11/01/05 ES51982 3 1/2 CAP AUTO DMM 5.4 Operating Timing ES51982 incorporates a dual slope ADC with four phases: ZI, AZ, INT and DINT. The timing of each phase is listed below. *Voltage /ohm/ADP measurement: Phase Time ZI 100ms AZ 100ms INT 100ms DINT 200ms Ps. In the voltage and ohm measurement with auto mode, if the range is changed, the internal clock rate will increase ten times and the new measurement cycle becomes 1/10 times of the original cycle until the range is stable. *Current mode Phase Time ZI 100ms AZ 100ms INT 100ms DINT 100ms *Continuity/diode measurement Phase Time ZI 10ms AZ 10ms INT 10ms DINT 20ms *Capacitance measurement: Range Total Measurement Time 2.000nF 0.5sec 20.00nF 0.5sec 200.0nF 0.5sec 2.000uF 0.5sec 20.00uF 0.5sec 200.0uF 1sec 2.000mF 2.5sec *.Frequency measurement one measurement cycle = 1.05 sec ps. In the frequency measurement with auto mode, if the range is changed, the internal clock rate will increase ten times and the new measurement cycle becomes 1/10 times of the original cycle until the range is stable. 18 11/01/05 ES51982 3 1/2 CAP AUTO DMM 6.Test circuit 1. Voltage test 4.Current test AGND OVSG 100 1K 10K 101K 1.11M D2 D1 1.0u 0.47u 1.0u OR1 VR5 VR4 VR3 VR2 ADO 88M ADI ACVL ACVH TEST5 0.1u 15K 10K 15K 5K 0.005 20A 0.045 0.45 2A mA 4.5 A mA uA V R 1 mA 45 100K uA uA IVSL 450 5.Frequency test -100mV F R E Q Voltage input 2.Resistor test 200 OVH OVSG 6.ADP test OR1 VR5 VR4 VR3 VR2 VA+ ADPin+ SGND AGND VAADP -100mV 100K ADPin- SGND AGND 3.Diode test AGND Z1 6V Z2 V- Fin 100 100 1K 10K 101K 1.11M 2.2u PTC 1.5K OVX PTC 1.5K IVSH 100K V R 10M Z1 6V Z2 AGND SGND 100 7. Low battery OVH PTC 1.5K 9V 10M 1.11M VR1 BA 680K TT VR2 270K LBAT9 0.1u AGND V- 0V OVSG 19 11/01/05 ES51982 3 1/2 CAP AUTO DMM 7.Application circuit 7.5V 5.6V ZI 0.1u + 450 uA uA mA 10u + 0.1u -3V 0.1 u HOLD RANGE SLACDC KEY FC5 FC4 FC3 FC2 FC1 NC C+ CNC SDO LBAT9 VVDGND AGND AGND uA 4.7u 3V C 1K 100K 1u 200 2.2u 9K Cp 10M 100K 470n 1.5K PTC 1815 -3V Note: In order to prevent IC from damaging by inappropriate operation, the Zener diodes MUST be required as protection. 20 11/01/05 4MHz -3V Display 20K (50)SEG13 SEG14 SEG15 SEG16 BKLIT RS232 NC FREQ SLEEP CA+ (40)CAR1K R9K VBAR NC VR1 SGND ADP VAVA+ + NC BKOUT NC XTAL NC OSC1 OSC2 NC BUZOUT BUZIN NC ANNUNC BP1 BP2 BP3 BP4 SEG01 SEG02 SEG03 SEG04 SEG05 SEG06 SEG07 SEG08 SEG09 SEG10 SEG11 SEG12 NC NC LCD NC V+ V+ 4.5 mA NC mA CL+ 0.1u CLA 0.45 2A 0.22u CIL 0.1u CAZL 0.045 20A 100K BUFL 0.005 SGND 100K IVSH(10) IVSL 100K OVX 100 100K 110pF OVH 1.5K OVSG PTC NC 100 OR1 1K Zener 6V VR5 10K C R 101K VR4 VR3 1.11M VR2(20) 10K TEST5 ACVL 5K ACVH NC 15K 15K 0.1u ADI 1u 1u NC 88M D1 D2 0.47u ADO NC 91K VRH 1u VR(30) 45 ES51982 3 1/2 CAP AUTO DMM Package 1 100 Pin QFP Package 2 Dimension Paramenters 21 11/01/05