ES51950(5000counts) Dual Display/Cap *Data hold function Features *Back light function • 5000 counts dual LCD display *Semi-auto Calibration Operation (Taiwan patent no.: 367334) • 128L QFP package • 3V DC power supply • Low pass filter for ACA measurement • ADC Conversion rate : 3.3 times/s • Band-gap reference voltage output • Full automatic measurement • CE selection (DC/AC 1010V, DC/AC 610V) *Voltage measurement: 500.0mV – 1000V • LCD segment check when power on *Current measurement: 50.00A/500.0A, 500A/5000A • Auto power off (30min/15min) *Flame rod DCuA mode measurement: 500.0uA/5000uA both manual ranges *Smart auto check for R/S/D/C mode Resistance: 500.0Ω~5.000MΩ Capacitance: 5.000nF~500.0uF (Taiwan patent no.: 326361) • Sleep state indicative signal output • Re-power on • On-chip buzzer driver • High Voltage (HV) danger indication • Low battery multi-level detection *Not contact AC electric field detection *Frequency mode active on sub-display for ACA 500.0Hz ~ 5000Hz *Resistance measurement: 500.0Ω – 50.00MΩ *Capacitance measurement: 5.000nF – 50.00mF (Taiwan patent no.: 323347, 453443) *Frequency counter with duty cycle display: 500.0Hz – 50.00MHz 5% – 95% (< 10kHz) • ZERO function for DCA mode • Voltage high crest factor detection (Taiwan patent no.: 234661) • Voltage & Current measured simultaneously ACV+ACA, DCV+DCA • Diode measurement & continuity check • Auto range temperature mode(500.0 0C /5000 0C) • Temperature mode with internal scale translation circuit from 0C to 0F • Push functions: *Single Select key operation: Zero for DCA Hz for ACA Description ES51950 is an integrated analog-to-digital converter (ADC) with dual 5,000-count LCD display, which 4-digit main-display (AC/DC Voltage) and 4-digit sub-display (AC/DC Current), automatic range selection, and 3V DC power supply. ES51950 could be designed for a clamp-meter with V & A measurement simultaneously. Automatic range selection is provided for voltage (AC/DC) measurement, resistance measurement, current measurement, capacitance measurement, and frequency counter. Other features include offset removing feature for DCA clampmeter, data holding, duty cycle measurement, diode measurement, temperature measurement, continuity checking, multi-level low battery detection, auto power off, re-power on, backlight driver, and buzzer output driver. *Range change function v2.3 1 10/06/25 B A ADO_A ADI_A TEST5A ACVLA ACVHA CSH+ CSHVAIVSL IVSH ADP RAZ_A BUF_A CAZ_A CINT_A CLN_A CLP_A VRH CLP_V CLN_V CINT_V CAZ_V BUF_V RAZ OHM C4 OHM C3 OHM C2 OHM C1 VR_A DACAO VR DACVO OR1 VR5 VR4 VR3 VR2 OVSG C 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 D 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 v2.3 CAL_nF APOSEL SVR S50V C_clamp Opt_nF LCDCAP OSC2 OSC1 BKOUT BZOUT ALARM BP1 BP2 BP3 BP4 SEG01 SEG02 SEG03 SEG04 SEG05 SEG06 SEG07 SEG08 SEG09 SEG10 SEG11 SEG12 SEG13 SEG14 SEG15 SEG16 SEG17 SEG18 SEG19 SEG20 SEG21 SEG22 102 101 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 ES51950(5000counts) Dual Display/Cap Application Clamp meter Pin Assignment LQFP-128L 1 1 2 CESEL TSEL ALARM1 DIS_LPF DISDGB DISDCA NC BKLIT SEL HOLD RANGE SAC FC4 FC3 FC2 FC1 CC+ LBAT9 VVV+ V+ DGND AGND AGND 3 ES51950 2 3 2 4 D SEG23 SEG24 SCL SDA CAL_EN FREQ BUZIN SLEEP LPFOUT LPC3 LPC2 LPC1 OVH1 OVH OVX R1K R9K CA+ CASGND TEST5V ADO_V ADI_V ACVH_V ACVL_V VR1 64 63 62 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 39 C B A 4 10/06/25 ES51950(5000counts) Dual Display/Cap Pin Description Pin No 1 2 3 Symbol ADO_A ADI_A TEST5_A Type O I O 4 ACVL_A O 5 ACVH_A O 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25-28 29 30 31 32 33 34 35 36 37 38 39 CSH+ CSHVAIVSL IVSH ADP RAZ_A BUF_A CAZ_A CINT_A CLN_A CLP_A VRH CLP_V CLN_V CINT_V CAZ_V BUF_V RAZ OHMC1-4 VR_A DAC_AO VR DAC_VO OR1 VR5 VR4 VR3 VR2 OVSG VR1 I/O I/O I I I I O O O O I/O I/O O I/O I/O O O O O O I O I O O O O O O O I 40 ACVL_V O 41 ACVH_V O 42 43 44 45 46 47 48 49 50 51 52 ADI_V ADO_V TEST5_V SGND CACA+ R9K R1K OVX OVH OVH1 I O O G I/O I/O O O I O O v2.3 Description Output of internal AC to DC OP Amp for ACA mode. Negative input of internal AC to DC OP Amp for ACA mode. Buffer output of SGND for ACA mode DC signal low input in ACA mode. Connect to negative output of external AC to DC converter. DC signal high input in ACA mode. Connect to positive output of external AC to DC converter. Cap for duty-cycle mode Cap for duty-cycle mode For ADP mode. De-integrating voltage negative input Current measurement input for higher range. Current measurement input for lower range. Measurement input in ADP mode. (Current/Temperature/NCV mode) Buffer output pin in AZ and ZI phase for ADC_A. Buffer output pin for ADC_A. Connect to integral resistor Auto-zero capacitor connection for ADC_A. Integrator output for ADC_A. Connect to integral capacitor. Negative connection for reference capacitor of ADC_A. Positive connection for reference capacitor of ADC_A. Output of band-gap voltage reference. Typically –1.23V Positive connection for reference capacitor of ADC_V. Negative connection for reference capacitor of ADC_V. Integrator output for ADC_V. Connect to integral capacitor. Auto-zero capacitor connection for ADC_V. Buffer output pin for ADC_V. Connect to integral resistor Buffer output pin in AZ and ZI phase for ADC_V. Filter capacitor connection1-4 for resistance mode. Reference input voltage in current mode or ADP. Typically –400mV DAC output for current mode or ADP input mode Reference input voltage in voltage mode. Typically –400mV DAC output for voltage mode Reference resistor connection for 500.00Ω range Voltage measurement ÷10000 attenuator(1000V) Voltage measurement ÷1000 attenuator(500.0V) Voltage measurement ÷100 attenuator(50.00V) Voltage measurement ÷10 attenuator(5.000V) Sense low voltage for resistance/voltage measurement Measurement Input. Connect to a precise 10MΩ resistor. DC signal low input in ACV mode. Connect to negative output of external AC to DC converter. DC signal high input in ACV mode. Connect to positive output of external AC to DC converter. Negative input of internal AC to DC OP Amp for ACV mode. Output of internal AC to DC OP Amp for ACV mode. Buffer output of OVSG for ACV mode Signal Ground. Negative auto-zero capacitor connection for capacitor measurement Positive auto-zero capacitor connection for capacitor measurement Connect to a precise 9KΩ resister for capacitor measurement. Connect to a precise 1KΩ resister for capacitor measurement. Sense input for resistance/capacitance measurement Output connection for resistance measurement Output connection for resistance measurement (Optional) 3 10/06/25 ES51950(5000counts) Dual Display/Cap 53 54 55 56 57 58 59 60 61 62 63-86 87-90 91 LPFC1 LPFC2 LPFC3 LPFOUT SLEEP BUZIN FREQ CAL_EN SDA SCL SEG24-SEG01 BP4-BP1 ALARM O O O O O I I I I/O O O O O 92 BUZOUT O 93 BKOUT O 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115-118 119 120 OSC1 OSC2 LCDCAP Opt_nF C_clamp S50V SVR APOSEL CAL_nF CESEL TSEL ALARM1 DIS_LPF DIS_DGB DIS_DCA NC BKLIT SEL HOLD RANGE SAC FC4-FC1 CC+ I O I I I I I I I I I O I I I I I I I I I O O 121 LBAT9 I 122 123 124 125 126 127 128 VVV+ V+ DGND AGND AGND P P O O P/G P/G P/G v2.3 Capacitor C1 connection for internal low-pass filter Capacitor C2 connection for internal low-pass filter Capacitor C3 connection for internal low-pass filter Capacitor C1 connection for internal low-pass filter Sleep mode indicator, asserts low in SLEEP mode. Pull to V- to enable the BUZOUT. Frequency counter input, offset V-/2 internally by the chip. Pulled to V- to enable the semi-auto calibration scheme. Input/Output from/to EEPROM 24C02 data Output to EEPROM 24C02 clock LCD segment output driver 01-24 (SEG signals) LCD backplane 1-4 (COM signals) LED control output driver for HV indication and NCV detection Outputs a 2KHz audio frequency signal for driving piezoelectric buzzer when BUZIN is low or functional key is active. If BKLIT function is enabled, this pin will change from V- to V+ For 60 sec, once press BKLIT pin again within 60 sec, this pin will Change back to V-. Crystal oscillator input connection Crystal oscillator output connection LCD bias voltage bypass capacitor connection Pull to V- to change the initial range to 50nF in Cap mode. Pull to V- to change the initial range to 5uF in Cap mode. Switch control for function selection Switch control for function selection Auto power off idle time selection Pulled to V- to enable the small capacitor calibration scheme. OL selection feature control pin in Voltage mode. Pulled to V- to cancel the 500oC auto range mode LED control output driver for short-circuit detected in Cont. mode. Pulled to V- to disable the low-pass-filter path in ACA mode Pulled to V- to disable the buzzer beeper when HV danger appears. Pulled to V- to disable DCA function in DCV mode. Not connected Back light function. Pulse to V- to set BKOUT pin output. Pulse to V- to enable function selection Pulse to V- to enable HOLD function. Pulse to V- to enable manual mode and manual range selection. Switch for AC/DC function selection. Switches for function selection. Negative capacitor connection for on-chip DC-DC converter. Positive capacitor connection for on-chip DC-DC converter. Multi-level low battery configuration input. Simple external resistor divider is required. Negative supply voltage. Negative supply voltage. Output of on-chip DC-DC converter and positive supply voltage. Output of on-chip DC-DC converter and positive supply voltage. Digital ground. Analog ground. Analog ground. 4 10/06/25 ES51950(5000counts) Dual Display/Cap 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- = -3.0V Parameter Power supply Operating supply current In DCV+DCA mode Voltage roll-over error Voltage nonlinearity Symbol Test Condition VNormal operation IDD In sleep mode ISS REV 10MΩ input resistor Best case straight NLV line Input Leakage Zero input reading Band-gap reference voltage VREF Open circuit voltage for 500Ω measurement Open circuit voltage for other Ω measurement Peak to peak backplane drive voltage 10MΩ input resistor 100KΩ resistor between VRH and AGND -3.5V≤ V- ≤-2.5V Min. -2.5 — — — Typ. -3.0 1.9 5 — Max -3.5 2.2 10 ±0.1 Units V mA µA %F.S1 — — ±0.1 %F.S1 -10 -000 1 000 10 +000 PA counts -1.29 -1.23 -1.17 V — -3.0 — V -1.19 -1.08 -0.97 V 2.9 3.1 3.3 V — 1.2 — µA — — — — 40-400 400-2000 2.15 1.82 — — — — Pin97-118 inputs Internal pull-high to 0V current Ipull-up AC frequency response at 5.000V range ±1% ±5% Multi-level low battery detector Vt1 Vt2 LBAT9 vs. V- 3dB Bandwidth for ACA mode f3dB Low-pass-filter ON v2.3 5 4 HZ V kHz 10/06/25 ES51950(5000counts) Dual Display/Cap Parasitic capacitance allowed in 5.000MΩ range RSDC smart mode RES sensitivity RSDC smart mode DIODE sensitivity RSDC scan mode CAP sensitivity Reference voltage temperature coefficient Capacitance measurement accuracy — Forward voltage TCRF 100KΩ resister between VRH/GND 0℃<TA<70℃ 5.0nF – 50mF — 200 0.8 pF V 400 — — pF — 100 — ppm/℃ -2.5 — 2.5 %F.S -3 — 3 counts Note: 1. Full Scale Function Description 1. Dual Display 1.1 Introduction ES51950 configures a dual display LCD driver for DMM applications. The dual display includes first-display and second-display. Each display has 4 digits to show up to 5000 counts. The simplified representation of dual display is shown below. First-display usually shows Volts readings in ACV/DCV mode or Hz readings in Frequency mode. Second-display usually shows Amps/Hz readings in ACA/DCA mode or Duty-cycle readings in Frequency mode. By the dual display feature, ES51950 can shows Amps and Volts readings at the same time. Other features achieved by dual display will be introduced in later sections. The full LCD configuration is shown at section 3.4 of page 24. Second Display A First Display V v2.3 6 10/06/25 ES51950(5000counts) Dual Display/Cap 1.2 Dual display V.S. measurement mode The dual display default mode configuration is shown at the table below. Main measurement mode DC voltage AC voltage NCV mode Resistance mode Capacitance mode Frequency mode Continuity Check Diode mode Smart RSDC mode Temperature mode DCuA mode First-display DC voltage AC voltage EF Resistance Capacitance Frequency Resistance Voltage R/S/D/C o C N/A Second-display (defaulted) N/A N/A Electrical field strength N/A N/A Duty cycle N/A N/A N/A o F DCuA 1.3 Push key operation With dual display, user can use single push key “SEL” to active the Volts and Amps readings simultaneously. Push function First-display Second-display SEL in DCV mode DC Voltage DCA1 Æ DCA/Zero2 (function selection) See Fig.1 SEL in ACV mode AC Voltage ACA ÅÆ ACA Hz3 (function selection) See Fig.2 SEL in Smart mode R/S/D/C auto scan N/A (function selection) see Fig. 3 Hold Stop updating Stop updating NOTE: 1. DCA mode is not available if DIS_DCA (pin108) is pulled to V-. 2. DCA/Zero means the readings shown on LCD is offset-cancelled readings. 3. Hz mode is the frequency reading of ACA mode. v2.3 7 10/06/25 ES51950(5000counts) Dual Display/Cap Fig.1 SEL key operation in DCV + DCA(zero) mode DCV DCV+DCA DCV+DCA ZERO DC DC DC 0.0 5 Push <1S AUTO A 4.8 9 9 A 4.8 9 9 V AUTO 4.8 9 9 V 0.0 0 Push <1S AUTO ZERO V Push >1S Fig. 2 SEL key operation in ACV + ACA(Hz) mode ACV ACV+ACA ACV+Hz of ACA AC AC AC Push <1S AUTO 2 1 9.9 9 0.9 3 A Push <1S AUTO V 2 1 9.9 6 0.0 Hz AUTO 2 1 9.9 V V Push >1S High Voltage warning Fig. 3 SEL key operation in Smart (R/S/D/C auto scan) mode R/S/D/C auto scan Resistance measurement Continuity measurement Diode measurement Capacitance measurement Push SEL key < 1s v2.3 8 10/06/25 ES51950(5000counts) Dual Display/Cap 2. Operating Modes 2.1. Semi-auto calibration scheme ES51950 includes DMM & CLAMP_ON meter features in single chip. DMM manufacturers need the calibration process in production. The traditional solution needs the variable resistors for calibration by manual adjustment. ES51950 provide another calibration scheme and the variable resistors could be ignored. When ES51950 is at OFF-state, pull CAL_EN (pin 60) to V- to active the calibration scheme after re-power on. A digital controlled voltage output will be active from DAC_AO & DAC_VO. When semi-auto calibration scheme is active, use HOLD (or BKLIT) key to decrease voltage and use RANGE key to increase the voltage. Decrease the reference voltage means the counts on display will be increased. Increase the reference voltage means the counts on display will be decreased. The adjustment step is approximate one count. If coarse adjustment is required, push HOLD (or BKLIT) and RANGE larger than one second to speed up to approximate 30 counts per second. After calibration process is finished, push HOLD (or BKLIT) and RANGE (less than one second) simultaneously to save the digital control code to external EEPROM (24C02). HOLD or BKLIT RANGE Display Count Up Display Count Down HOLD + RANGE BKLIT + RANGE v2.3 Save Calibration data to EEP EEPROM ROM 9 10/06/25 ES51950(5000counts) Dual Display/Cap The semi-auto calibration scheme supports the following seven measurement modes. When CAL_EN pin is active, set the proper function switches and push SEL key to choose the target measurement mode. When mode is selected, the LCD segment of Unit at related measurement will be blinking. Mode DC Voltage measurement AC Voltage measurement Default range for CAL Remark Accuracy of other 5.000V ranges is guaranteed by external resistor Lower range in auto 50.00A or 500.0A or 5000A ACA mode 500uA or 5000uA 50.00nF Set CAL_nF to VLower range in Auto o o 500.0 C or 5000 C Temperature mode DC Current measurement AC Current measurement DC uA measurement Capacitor measurement Temperature measurement After calibration procedure is finished, set ES51950 to OFF-state and set CAL_EN to DGND to return to normal mode operation after re-power on. 2.2. Voltage Measurement A re-configurable voltage divider automatically provides a suitable range in voltage measurement mode. The following table summarizes the full-scale ranges in each configuration. Configuration 1 VR1 VR2 VR3 VR4 VR5 Full Scale Range 500.0mV 5.000V 50.00V 500.0V 1000V Divider Ratio 1 1/10 1/100 1/1000 1/10000 Resister Connection VR1 (10MΩ) VR2 (1.111MΩ) VR3 (101KΩ) VR4 (10.01KΩ) VR5 (1KΩ) Note: 1. 500.0mV range only exists in manual mode. 2.2.1 CE selection & high voltage (HV) indication ES51950 has a CE selection feature archived by configuring the pin CESEL. In automatic voltage mode, ES51950 will show OL when the voltage is over than the overflow level. If CESEL is connected to V- or DGND, ES51950 will have a 610.0V or 1010V overflow level in voltage mode relatively.. The configuration of CESEL is listed below. For fully automatic voltage modes: CESEL VDGND or floating v2.3 DCV 610V 1010V 10 ACV 610V 1010V 10/06/25 ES51950(5000counts) Dual Display/Cap During voltage measurement is in operation (DCV or ACV), the HV indication will be active when input voltage is larger than 30V or OL in manual range. The HV indication includes: z HV warning LCD segment active z Buzzer output active if DIS_DGB (pin107) is kept floating z ALARM (pin91) LED output active. 2.2.2 NCV mode ES51950 supports a non-contact AC voltage measurement, which is called electric field measurement also. The EF mode is selected by setting function control mode FC1-FC4 = [1,0,0,1]. The ADC input is configured from ADP pin vs. SGND. When no or less electric field is detected, the first-display LCD shows “EF” and the second-display LCD shows “Blank”. If the electric field is detected, the strength will be showed on the second-display LCD by “-“ not digits type. Level 1(equivalent to 12.5% full scale of ADC) is “-“ and the level 4(equivalent to 100% full scale of ADC) is “----“. Additional beeper (BUZOUT pin) and LED alarm (ALARM pin) will be output from ES51950. The frequency of buzzer and LED alarm depends on the strength of electric field also. The Faster beeper means the stronger electric field (AC voltage) is sensed. MANU LEVEL 1 (12.5%) LEVEL 2 (25%) LEVEL 3 (50%) - -- --- EF MANU MANU EF EF LEVEL 4 (100%) ---MANU EF EF test circuit 100k EFin+ ADP 88M EFin- SGND AGND -400mV v2.3 VA- 11 10/06/25 ES51950(5000counts) Dual Display/Cap 2.3 Current measurement for clampmeter (1) ACA/DCA ES51950 has 2 automatic and 3 manual current measurement modes for Clampmeter. The following table summarizes the full-scale range of each mode. When ES51950 operate in the automatic VA1 ~ VA2, it takes high input from IVSH/IVSL (higher range/lower range), low input from SGND and reference voltage from VR_A (pin29). When ES51950 operates in the manual VA3 ~ VA5, It takes high input from ADP, low input from SGND and reference voltage from VA- (pin8). Mode VA1 VA2 VA3 VA4 VA5 FC1~4 0,0,0,0 0,0,0,1 0,1,0,0 0,1,0,1 0,1,1,0 Full Scale 50.00A / 50.00A 500.0A / 5000A 50.00A 500.0A 5000A Input Terminal IVSL/IVSH V.S. SGND (500mV) IVSL/IVSH V.S. SGND (500mV) ADP V.S. SGND (500mV) ADP V.S. SGND (500mV) ADP V.S. SGND (500mV) Note: 1. In DCA current modes (SAC = 0) , ES51950 provides Zero function (push SEL key) for offset removing. (2) DCuA mode ES51950 has 2 manual DCuA current measurement modes for flame rod application. The following table summarizes the full scale range of each mode. Mode DCuA1 DCuA2 FC1~4 0,0,1,0 0,0,1,1 Full Scale 500.0uA 5000uA Input Terminal ADP V.S. SGND (500mV) ADP V.S. SGND (500mV) (3) Low pass filter (LPF) mode for ACA mode A 3rd order low-pass filter (3dB bandwidth = 4kHz typ.) with is built in ES51950 to reduce the influence of high frequency noise. The LPF mode is active in ACA only if DIS_LPF is connected to DGND or floating. v2.3 12 10/06/25 ES51950(5000counts) Dual Display/Cap 2.4 Resistance Measurement ( R ) A re-configurable 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 500.0Ω 5.000KΩ 50.00KΩ 500.0KΩ 5.000MΩ 50.00MΩ Relative Resistor OR1 VR5 VR4 || VR1 VR3 || VR1 VR2 || VR1 VR1 Equivalent value 100Ω 1KΩ 10KΩ 100KΩ 1MΩ 10MΩ 2.5 Capacitance Measurement ( C ) The following table summarizes the eight ranges of capacitance measurement mode. Configuration C1 C2 C3 C4 C5 C6 C7 C8 Full Scale Range 5.000nF 50.00nF 500.0nF 5.000uF 50.00uF 500.0uF 5.500mF 50.00mF Relative Resistor Ratio to C2 range CAL Ratio to C2 range R9K / R1K R9K / R1K R9K / R1K R9K / R1K R9K / R1K 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 main-display shows dIS.C 2. Discharging through the chip is quite slow. We recommend users to discharge the capacitor with some other apparatus. 3. The C2 range is calibrated by the variable resistance near to the OVX pin when CAL_nF (pin 102) is kept floating or use the semi-auto calibration scheme when CAL_nF is set to V-. 4. The C1 range zero offset could be compensated by the small capacitors near to OVH pin. 5. The C7 and C8 measurement period is depended on the capacitance of input terminals. v2.3 13 10/06/25 ES51950(5000counts) Dual Display/Cap 2.6 Continuity Check ( S ) Continuity check shares the same configuration with 500.0Ω manual resistance measurement mode and has buzzer output to indicate continuity. The buzzer generates 2KHz beep and ALARM1 (pin 105) drive high output (V+ level) whenever the reading is less than 30Ω. The ES51950 built in a high speed short detection circuit and the detection could be less than 10ms. 2.7 Diode Measurement ( D ) Diode measurement mode shares the same configuration with 5.000V manual voltage measurement mode and has buzzer output to indicate continuity. The buzzer generates a 2KHz sound and Alarm1 (pin 105) drive high output (V+ level) whenever the reading is less than 30mV. If the test circuit is open or the voltage drop between the two ports of the diode under test is larger than 2V, the LCD panel will show “OL”. 2.8 Frequency counter In frequency mode, main-display shows frequency and sub-display shows duty cycle at the same time. The time base of the frequency counter is derived from an external crystal oscillator by Tcounter = 4,000,000 Fosc 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 seven decades, from 500.0Hz to 50.00MHz. The following table summarizes the full-scale range of the frequency counter. Configuration FR1 FR2 FR3 FR4 FR5 FR6 Full Scale range 500.0Hz 5.000KHz 50.00KHz 500.0KHz 5.000MHz 50.00MHz *If input frequency is less than 5.0Hz, ES51950 will show 0.0Hz v2.3 14 10/06/25 ES51950(5000counts) Dual Display/Cap 2.9 Duty Cycle measurement The duty cycle measurement is available in frequency mode simultaneously. The duty cycle mode range is available within 5.0% to 95.0% (< 10kHz@3Vpp). The minimum resolution is 0.1%. If the source frequency duty cycle is smaller than 1.0%, the 0.0% will be shown on the LCD display. If the duty cycle is larger than 98.9%, the OL will be shown on the LCD sub-display. When the frequency is zero, the duty cycle display will be 0.0%. FREQ + Duty cycle 5 0.0 % AUTO 4.0 0 0MHz 2.10 Temperature measurement mode Temperature measurement mode takes input signal from ADP pin and reference voltage from VA-. ES51950 has a built-in ºC-to-ºF scale translation circuit, and only needs an external ºC scale application circuit. The application circuit for ºF scale is not required. The ºC & ºF readings are shown on the dual-display LCD simultaneously. In temperature2 measurement mode, the default range is 5000 ºC or 9032 ºF manual range. In temperature1 measurement mode, the default range is 500.0/5000 ºC or 932.0/9032 ºF auto range. The TSEL pin (pin104) is pulled to V-, the temperature1 measurement mode will be set to 500.0 ºC manual mode. Range Temp1 Temp2 v2.3 Full scale range Auto 500.0℃ / 5000℃ Manual 5000℃ Input terminal ADP V.S. SGND (50mV/500mV) ADP V.S. SGND (500mV) 15 10/06/25 ES51950(5000counts) Dual Display/Cap 2.11 Multi-level low battery voltage detection ES51950 provides a voltage detection input (pin 121: LBAT9) for multi-level low battery application. There are two internal voltage reference Vt1 & Vt2 for comparing with LBAT9. If LBAT9 is larger than Vt1, the LCD segment of SLB3 – SLB1 will active always. This status implies Full battery. When LBAT9 is less than Vt1 but larger than Vt2, the LCD segment of SLB3 will disappear and this status implies Half battery. When LBAT9 is less than Vt2, the LCD segment of SLB2 will disappear and this status implies Low battery. When the Low battery status lasts for 10 seconds, the LCD segment of SLB1 will be blinking. When the SLB1 is blinking for 20 seconds, the operation of meter will be inhibited and LCD panel will show “ Lo.bt”. In this case, it is suggested to replace a new battery immediately. After “Lo.bt” appears and lasts for 60 seconds, ES51950 will enter to auto power off mode. Full battery Half battery Low battery condition > 30s Operation not allowed Low battery blinking AUTO AUTO AUTO AUTO DC DC DC DC 1.8 0 0 V 1.8 0 0 V 1.8 0 0 Low battery test circuit (a) L o.b t Low battery test circuit (b) 3V 9V BA 150K BA LBAT9 TT 0.1u 470K 910K LBAT9 TT AGND V- 0.1u 300K 0V v2.3 V AGND V- 0V 16 10/06/25 ES51950(5000counts) Dual Display/Cap 2.12 Auto power off (APO) and idle time selection ES51950 has a default auto power off function. If the meter is idle for more than the given Idle Time, the chip automatically turns the power off. The idle time to trigger the auto power off function is determined by pin ‘APOSEL’. If pin APOSEL is connected to V-, the Idle Time will be set to 30 minutes. If pin APOSEL is connected to DGND or floating, the Idle Time will be set to 15 minutes. When APO happens, the state of the meter is saved. The APO sign on the LCD panel indicates whether the auto power off is enabled or not. If user might want to disable Auto power off, power on the meter when any of the push functions, except for HOLD, is pressed down. Note: 1. Powering on the meter while pressing HOLD and lasts 2 seconds turns on all LCD segments until HOLD is pressed again. 2. When low battery status happened (LCD show “Lo.bt”), the APO idle time will be reset to 60 sec. 2.13 Sleep The meter enters sleep mode after auto power off. The SLEEP pin asserts low (V-) in the sleep mode, and asserts high (V+, not 0V) after re-power on. 2.14 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. v2.3 17 10/06/25 ES51950(5000counts) Dual Display/Cap 3. Measurement Mode Switching Measurement mode depends on the logic level of SVR, S50V, SAC, FC1, FC2, FC3 and FC4. SVR S50V SAC FC1 FC2 FC3 FC4 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 X X X X X X X X X X X X X X X X X X X 0 0 0 0 0 1 1 1 1 1 X X X X X 0 0 0 0 0 1 1 1 1 1 X X X X X X X X X X X X X X 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 X X X X 0 0 0 0 1 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1 1 1 0 0 1 1 1 0 0 1 1 1 0 0 1 1 1 0 0 1 1 1 0 0 1 1 1 0 0 0 0 0 0 1 1 1 1 1 1 1 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 0 0 0 0 1 1 1 0 0 1 1 0 0 1 1 0 0 1 1 0 1 0 1 0 0 1 0 1 0 0 1 0 1 0 0 1 0 1 0 0 1 0 1 0 0 1 0 1 0 0 1 0 1 0 1 0 1 0 1 0 1 0 1 Function mode ACV (5.000V) + ACA (50.00A / 500.0A) ACV (5.000V) + ACA (500.0A / 5000A) ACV (5.000V) + ACA (50.00A) ACV (5.000V) + ACA (500.0A) ACV (5.000V) + ACA (5000A) ACV (50.00V) + ACA (50.00A / 500.0A) ACV (50.00V) + ACA (500.0A / 5000A) ACV (50.00V) + ACA (50.00A) ACV (50.00V) + ACA (500.0A) ACV (50.00V) + ACA (5000A) ACV (500.0V) + ACA (50.00A / 500.0A) ACV (500.0V) + ACA (500.0A / 5000A) ACV (500.0V) + ACA (50.00A) ACV (500.0V) + ACA (500.0A) ACV (500.0V) + ACA (5000A) DCV (5.000V) + DCA (50.00A / 500.0A) DCV (5.000V) + DCA (500.0A / 5000A) DCV (5.000V) + DCA (50.00A) DCV (5.000V) + DCA (500.0A) DCV (5.000V) + DCA (5000A) DCV (50.00V) + DCA (50.00A / 500.0A) DCV (50.00V) + DCA (500.0A / 5000A) DCV (50.00V) + DCA (50.00A) DCV (50.00V) + DCA (500.0A) DCV (50.00V) + DCA (5000A) DCV (500.0V) + DCA (50.00A / 500.0A) DCV (500.0V) + DCA (500.0A / 5000A) DCV (500.0V) + DCA (50.00A) DCV (500.0V) + DCA (500.0A) DCV (500.0V) + DCA (5000A) DCuA (500.0uA) DCuA (5000uA) FREQ + Duty cycle NCV (EF) 1 Temp (500.0 oC / 5000 oC) (AUTO) o Temp (5000 C) R (Resistance mode) S (Continuity mode) D (Diode check mode) C (Capacitance mode)2,3 R,S R,S,D R,S,D,C2,3 Auto scan RSDC Remark VA1 VA2 VA3 VA4 VA5 VA1 VA2 VA3 VA4 VA5 VA1 VA2 VA3 VA4 VA5 VA1 VA2 VA3 VA4 VA5 VA1 VA2 VA3 VA4 VA5 VA1 VA2 VA3 VA4 VA5 DCuA1 DCuA2 Fmode EFmode Temp1 Temp2 R S D C RS RSD RSDC Smart X means “don’t care”. 1 50mV full scale is for 500 oC range and 500mV full scale is for 5000 oC range. When TSEL (pin104) is pulled to V-, the 500oC range is fixed 2 Set the C_clamp (pin98) to V- to change initial range of C to 5.000uF. Set the Opt_nF(pin97) to V- to change initial range of C to 50.00nF. 3 Set the Opt_nF(pin97) to V- to change initial range of C to 50.00nF. v2.3 18 10/06/25 ES51950(5000counts) Dual Display/Cap Push function All the enabled push functions will be reset when the measurement mode is changed by rotary switch. The following table lists the available function versus every measurement mode. DCV DCV + DCA ACV ACV + ACA DCuA Frequency NCV ( EF ) 3 Temp1 Temp2 Resistance Continuity Diode Capacitance R , S1 R , S1 , D R , S1 , D , C Smart2 RANGE HOLD SEL BKLIT O O ( V only) O O ( V only) X O X O X O X X O O ( R only) O ( R only) O (R/C only) X O O O O O O O O O O O O O O X O O O O O O X X X X X X X X X O O O O O O O O O O O O O O O O O O X O O Note: 1 Continuity mode 2 Auto check for RSDC mode: Max range for R is 5.000MΩ and Max range for C is 500.0uF 3 Auto range configuration v2.3 19 10/06/25 ES51950(5000counts) Dual Display/Cap 3.1. HOLD and Delay Hold feature 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. ES51950 provides a Delay HOLD feature. To activate Delay HOLD feature, press down the HOLD bottom and last for 2 seconds. The meter will delay for 6 seconds, than enters HOLD mode. In the 6-secnod delayed time, the HOLD symbol on LCD panel will blink. HOLD function and the delayed state can be cancelled by changing the measurement mode, pressing RANGE, or push HOLD again. Normal mode Push < 2s HOLD mode (Auto/Manual) Push < 2s (Manual) Push > 2s Push < 2s Push > 2s 6sec past Delay State (Auto/Manual) 3.2. Range RANGE pin configuration is shown below. It is available for voltage, resistance, capacitance, frequency and temperature (Temp1) modes. 1 push < 1 sec Automatic Mode Manual Mode 1 push > 1 sec Range up 1 push < 1 sec v2.3 20 10/06/25 ES51950(5000counts) Dual Display/Cap Measurement Mode V(DC/AC) Auto A(DC/AC) Auto A(AC/DC) Auto Manual VRi → VRi + 1, VR2 – VR5 VR5 → VR1 IR1 – IR2 N/A3 IR1－IR2 N/A3 Manual A(AC/DC) fixed fixed Manual DCuA fixed fixed Capacitance Ω Continuity Diode Temp1 Frequency Ci → Ci + 1, C8 → C1 ORi → ORi + 1, OR1 – OR6 OR6 → OR1 fixed fixed fixed fixed T1 → T2 T1-T2 T2 → T1 C1 – C8 FR1 – FR6 FRi → FRi + 1 FR6 → FR1 Control Range Initial Range 500.0mV – 1000V 5.000V1 500.0A – 5000A 50.00A – 500.0A 50.00A 500.0A 5000A 500.0uA 5000uA 500.0A 50.00A 50.00A 500.0A 5000A 500.0uA 5000uA 5.000nF– 50.00mF 5.000nF2 500.0Ω – 50.00MΩ 500.0Ω 500.0Ω 5.000V 500.0Ω 5.000V 500.0oC – 5000oC 500.0oC 500.0Hz – 50.00MHz 500.0Hz Note: Pushing RANGE resets all existing special modes. 1 Initial range depends on status of SVR & S50V. See Measurement Mode Switching 2 Initial range depends on status of C_clamp & Opt_nF. v2.3 21 10/06/25 ES51950(5000counts) Dual Display/Cap 3.3. ZERO function In manual DC 50.00A, 500.0A and 5000A, auto DC 50.00A/500.0A and auto DC 500.0A/5000A mesurement modes, ES51950 provides Zero function to remove the residual current value. During DCV and DCA mode are active simultaneously, push SEL key less than one second to enter Zero mode. In Zero mode, second-display shows DN+K - DN, where N = 1, 2, 3, … , DN is the last conversion value before SEL is pushed, and DN+K is the current conversion value. If SEL is pushed again in Zero mode, second-display will update the DN value and displays the DN+K - DN again. The meter returns to DCV operation only if SEL is pressed and held for longer than one second. In 2-range auto DCA modes for clampmeter (500.0A/5000A or 50.00A/500.0A), the system will stay in automatic mode, even if the Zero function is activated. In other words, it could achieve real automatic operation. In automatic mode, Zero function could not be entered from higher range, but it could be still activated if current range is lower one. This is because most residual current value is so small that the range should stay at lower one in automatic mode. When enter Zero mode in lower range, the system will store the nonzero counts (residual current value). If the range goes up to higher one automatically, the non-zero counts will be divided by ten. So this function will still work well in automatic modes. State diagram for Zero mode: Original State (DCV only) Press SEL < 1s DCV+DCA Press SEL > 1s Press SEL < 1s ‘Zero’ Active Press SEL < 1s Main-display: DN+K - DN v2.3 22 10/06/25 ES51950(5000counts) Dual Display/Cap Miscellaneous The conditions, which the meter turns on the buzzer, include: (1) Changing measurement mode generates one beep. (2) Pressing any of the push functions 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 30Ω(30mV) (6) Auto power off generates a 2KHz beep which lasts for 1.5 seconds. The following figures show the output waveform from the BUZOUT pin. 0.5 mS (a) Continuous 2KHz beep 0.15 sec 0.3 sec (b) 3.33 beep/sec v2.3 23 10/06/25 ES51950(5000counts) Dual Display/Cap 3.4. LCD Panel v2.3 24 10/06/25 ES51950(5000counts) Dual Display/Cap LCD Backplane Waveform V- +3.1 V- +3.1 V- V- V- +3.1 V- +3.1 V- V- V- +3.1 V- +3.1 VV- +3.1 VV- +3.1 V- 3.5. LCD display on condition LCD Annunciator V A Ω F % Hz Hz2 DC AC AUTO MANU SCAN HOLD m1 µ1 n m2 µ2 M K ℃ ℉ v2.3 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 duty cycle measurement. Hz for Frequency mode (voltage signal to FREQ input) Hz for ACA mode (ADP/IVSH/IVSL) In DC voltage or current mode. In AC voltage or current mode. When automatic range selection is enabled. (Voltage, resistance, capacitance, frequency mode) In manual mode. When smart (resistance, continuity, diode, capacitance auto check mode) is active. 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 measurement mode and the full scale range is in the order of 10-3. In DCuA current measurement mode and the full scale range is 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 When the reading is exceeding 30V or OL in DCV or ACV, the HV warning symbol will be displayed. In temperature measurement mode and when the unit is ℃ In temperature measurement mode and when the unit is ℉ 25 10/06/25 ES51950(5000counts) Dual Display/Cap SLB3 SLB2 SLB1 APO v2.3 When voltage (ref. to V-) of LBAT9 pin is less than Vt1, SLB3 will disappear. When voltage (ref. to Vo) of LBAT9 pin is less than Vt2, SLB2 will disappear. When SLB2 disappears for 8 seconds, SLB1 will be blinking. When auto power off function is enabled. 26 10/06/25 ES51950(5000counts) Dual Display/Cap 3.6. Operating Timing ES51950 incorporates a dual slope ADC with four phases: ZI, AZ, INT and DINT. The timing of each phase is listed below. *Voltage / Current / Ohm / ADP / Temperature (High range) measurement: Phase ZI AZ INT DINT Period 50ms 24ms 100ms 126ms * Temperature mode (Low range: 500oC mode) Phase ZI AZ INT DINT Period 50ms 24ms 1000ms 126ms *Capacitance measurement: Range 6.600nF 66.00nF 660.0nF 6.600μF 66.00μF 660.0μF 6.600mF 66.00mF Total Measurement Time 0.35 sec 0.35 sec 0.95 sec 0.7 sec 0.7 sec 1.4 sec 2.8 sec (max) 14.0 sec (max) *Frequency + Duty cycle mode measurement In range 500.0Hz~50MHz, the measurement cycle = 1.05 sec P.S. 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. v2.3 27 10/06/25 1 U1 ADO_A ADI_A TEST5A ACVLA ACVHA CSH+ CSHVAIVSL IVSH ADP RAZ_A BUF_A CAZ_A CINT_A CLN_A CLP_A VRH CLP_V CLN_V CINT_V CAZ_V BUF_V RAZ OHMC4 OHMC3 OHMC2 OHMC1 VR_A DACAO VR DACVO OR1 VR5 VR4 VR3 VR2 OVSG V+ V- 2 DIS_DCA DIS_DGBP DIS_LPF ALARM1 TSEL CESEL CAL_nF APOSEL SVR S50V C_clamp Opt_nF LCDCAP OSC2 OSC1 BKOUT BZOUT ALARM BP1 BP2 BP3 BP4 SEG01 SEG02 SEG03 SEG04 SEG05 SEG06 SEG07 SEG08 SEG09 SEG10 SEG11 SEG12 SEG13 SEG14 SEG15 SEG16 SEG17 SEG18 SEG19 SEG20 SEG21 SEG22 V- 3 102 101 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 ES51950 R22 47K 5 6 7 8 + 2.2uF APOSEL SVR S50V C_clamp Option_nf C4 BKOUT BZOUT ALARM BP1 BP2 BP3 BP4 SEG01 SEG02 SEG03 SEG04 SEG05 SEG06 SEG07 SEG08 SEG09 SEG10 SEG11 SEG12 SEG13 SEG14 SEG15 SEG16 SEG17 SEG18 SEG19 SEG20 SEG21 SEG22 U2 SDA SCL WP VCC 24C02 V- 4 3 2 1 V- V- 4MHz 0.1uF Y1 GND A2 A1 A0 R25 2.2K PTC 1 J4 Q10 C1815 BKLIT HOLD RANGE SEL S50V SVR SAC FC4 FC3 FC2 FC1 Fin BKOUT D3 LED SW5 SW6 SW7 SW8 SW2 SW3 SW11 SW12 SW13 SW14 SW15 4 V- 100 R30 10K R9 R6 100K BKLIT HOLD V- RANGE SEL S50V SVR SAC FC4 FC3 FC2 FC1 BZOUT VQ11 C1815 ALARM D1 LED ALARM1 D2 LED Hi-Z R1 100K R7 R8 R2 100K V- BZ1 Buzzer R31 10K TRMS Circuit Q12 KN2907 100 100 5 ADI_A - VS V- V- Q1 C1815 Q2 C1815 C34 22uF + VS R32 + VS C30 10uF C31 + - VS 200K - VS 200K 1 2 3 4 5 6 7 1 2 3 4 5 6 7 C36 Bat- SW1 10uF Power Switch 5.6V 14 13 12 11 10 9 8 14 13 12 11 10 9 8 6 V- 2.2uF + C39 ACVH_V + VS 2.2uF + C38 ACVH_A + VS ZR2 7.5V V+ 0.1uF 10uF 0.1uF 3.3uF C6 C5 C9 C8 ZR1 Bat+ DC3.0V U3 3.3uF Vin + VS En NC - VS NC CAV NC dB COMMON BUF out RL BUF in Iout C37 ES636 (BIN 6) U4 Vin + VS En NC - VS NC CAV NC dB COMMON BUF out RL BUF in Iout ES636 (BIN 6) Sheet of Drawn By: 6 Revision ES51950_RMS Circuit 8-Jun-2010 F:\Protel file\KA030.ddb Number C35 22uF 10uF ADI_V R33 + VS 10uF C33 + + VS C32 - VS 10uF Title B Size + SW4 CAL_En 200 C29 Semi-Auto Calibrate Active Mode to V Normal Mode to GND R29 C1815 + C25 Q9 Date: File: + C27 Q8 C1815 5 + 1uF R21 9K 180K 2K 2K C26 220pF Close to IC Q7 C1815 4 + ACVH_A 10nF ADI_A C1 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 Detailed C22 R20 1K R26 R27 R28 C1815 3 + + + Metallized Polypropylene Film Capacitor : C11, C12 IVSL IVSH ADP 100K 100K 100K 0 470K 220nF 220nF 220nF 100 1K 10.0K 101K 1.111M 220nF 220nF 360K 120K 22n 47n 220nF 470n VRH 100nF R3 R4 R5 R10 R11 C10 C11 C15 C16 Detailed C12 C13 R12 R13 C17 C18 C14 C19 R14 R15 R16 R17 R18 10M Q5 C1815 Q6 0 ~ 100pF 2 + D C C21 1uF Gnd Vin R19 Bottom Ground Plane SW10 ACV RMS VR1 1 J1 1 J2 C1815 FC1 FC2 FC3 FC4 SAC RANGE HOLD SEL BKLIT 39 40 41 42 43 44 45 46 C3 470nF 47 48 49 50 51 52 53 C23 1nF C24 220pF 54 55 C28 4.7nF 56 57 SLEEP 58 BUZIN 59 CAL_EN 60 61 SDA 62 SCL 63 SEG24 64 SEG23 C20 1uF SW9 SW_RC R23 2.2K PTC R24 2.2K PTC Q3 C1815 Q4 LBAT9 C2 470nF 128 127 126 125 124 123 122 121 120 119 118 117 116 115 114 113 112 111 110 109 108 107 106 105 104 103 AGND AGND DGND V+ V+ VVLBAT9 C+ CFC1 FC2 FC3 FC4 SAC RANGE HOLD SEL BKLIT NC DISDCA DISDGB DIS_LPF ALARM1 TSEL CESEL VR1 ACVL_V ACVH_V ADI_V ADO_V TEST5V SGND CACA+ R9K R1K OVX OVH OVH1 LPC1 LPC2 LPC3 LPFOUT SLEEP BUZIN FREQ CAL_EN SDA SCL SEG24 SEG23 ACVH_V ADI_V Ver:4 D C B A 10/06/25 28 v2.3 B A 1 + ES51950(5000counts) Dual Display/Cap 4. Application Circuit 4.1 EEPROM is used (AC RMS circuit) 0 ~ 100pF + C1 100K 100K 100K 0 470K 220nF 220nF 220nF ADO_A ADI_A TEST5_A ACVL_A ACVH_A 10nF 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 ADO_A ADI_A TEST5A ACVLA ACVHA CSH+ CSHVAIVSL IVSH ADP RAZ_A BUF_A CAZ_A CINT_A CLN_A CLP_A VRH CLP_V CLN_V CINT_V CAZ_V BUF_V RAZ OHMC4 OHMC3 OHMC2 OHMC1 VR_A DACAO VR DACVO OR1 VR5 VR4 VR3 VR2 OVSG U1 V+ V- 2 C27 C25 DIS_DCA DIS_DGBP DIS_LPF ALARM1 TSEL CESEL SW4 + CAL_En CAL_nF APOSEL SVR S50V C_clamp Opt_nF LCDCAP OSC2 OSC1 BKOUT BZOUT ALARM BP1 BP2 BP3 BP4 SEG01 SEG02 SEG03 SEG04 SEG05 SEG06 SEG07 SEG08 SEG09 SEG10 SEG11 SEG12 SEG13 SEG14 SEG15 SEG16 SEG17 SEG18 SEG19 SEG20 SEG21 SEG22 V- 200 C29 Semi-Auto Calibrate Active Mode to V Normal Mode to GND R29 3 102 101 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 ES51950 R22 47K 5 6 7 8 2.2uF APOSEL SVR S50V C_clamp Option_nf C4 Q9 V- V- V- 1 J4 Q10 C1815 4 3 2 1 4MHz 0.1uF Y1 GND A2 A1 A0 C1815 R25 2.2K PTC 24C02 SDA SCL WP VCC U2 BKOUT BZOUT ALARM BP1 BP2 BP3 BP4 SEG01 SEG02 SEG03 SEG04 SEG05 SEG06 SEG07 SEG08 SEG09 SEG10 SEG11 SEG12 SEG13 SEG14 SEG15 SEG16 SEG17 SEG18 SEG19 SEG20 SEG21 SEG22 Q8 C1815 BKLIT HOLD RANGE SEL S50V SVR SAC FC4 FC3 FC2 FC1 Fin BKOUT D3 LED SW5 SW6 SW7 SW8 SW2 SW3 SW11 SW12 SW13 SW14 SW15 4 V- 100 R30 10K R9 R6 100K BKLIT HOLD V- RANGE SEL S50V SVR SAC FC4 FC3 FC2 FC1 BZOUT VQ11 C1815 ALARM D1 LED ALARM1 D2 LED Hi-Z R1 100K R7 100 5 V- V- 3.9K 1uF + C32 1uF + C34 B Size Title 1N4148 D6 3.9K 1N4148 D4 100 R36 R34 15K R37 R32 15K R8 R2 100K V- BZ1 Buzzer R31 10K Average Circuit Q12 KN2907 Date: File: Q1 C1815 Q2 C1815 ADO_V D5 C35 1uF 10K C33 1uF 10K Bat- SW1 Power Switch 5.6V 0.1uF 6 V- ACVL_A C31 0.1uF ACVH_A ADI_A TEST5_A ACVL_V C30 0.1uF ACVH_V ADI_V TEST5_V ZR2 7.5V V+ 0.1uF 10uF 10uF 56K 56K R42 56K R35 15K C37 4.7uF R41 R40 56K R33 15K C36 4.7uF C6 C5 C9 C8 ZR1 Bat+ DC3.0V R38 R39 1N4148 ADO_A D7 1N4148 R43 Sheet of Drawn By: 6 Revision ES51950_AVG Circuit 8-Jun-2010 F:\Protel file\KA030.ddb Number + 1uF R21 9K 180K 2K 2K C26 220pF Close to IC Q7 C1815 5 + 10M Detailed C22 R20 1K R26 R27 R28 C1815 4 + 100 1K 10.0K 101K 1.111M 220nF 220nF 360K 120K 22n 47n 220nF 470n VRH 100nF R3 R4 R5 R10 R11 C10 C11 C15 C16 Detailed C12 C13 R12 R13 C17 C18 C14 C19 R14 R15 R16 R17 R18 R19 Bottom Ground Plane Vin Gnd Q5 C1815 Q6 3 + 1 IVSL IVSH ADP C21 1uF VR1 1 J1 1 J2 C1815 0 ~ 100pF 2 + + + Metallized Polypropylene Film Capacitor : C11, C12 C20 1uF SW9 SW_RC R23 2.2K PTC R24 2.2K PTC Q3 C1815 Q4 FC1 FC2 FC3 FC4 SAC RANGE HOLD SEL BKLIT 39 40 41 42 43 44 45 46 C3 470nF 47 48 49 50 51 52 53 C23 1nF C24 220pF 54 55 C28 4.7nF 56 57 SLEEP 58 BUZIN 59 CAL_EN 60 61 SDA 62 SCL 63 SEG24 64 SEG23 D C B A 1 LBAT9 C2 470nF 128 127 126 125 124 123 122 121 120 119 118 117 116 115 114 113 112 111 110 109 108 107 106 105 104 103 AGND AGND DGND V+ V+ VVLBAT9 C+ CFC1 FC2 FC3 FC4 SAC RANGE HOLD SEL BKLIT NC DISDCA DISDGB DIS_LPF ALARM1 TSEL CESEL VR1 ACVL_V ACVH_V ADI_V ADO_V TEST5V SGND CACA+ R9K R1K OVX OVH OVH1 LPC1 LPC2 LPC3 LPFOUT SLEEP BUZIN FREQ CAL_EN SDA SCL SEG24 SEG23 ACVL_V ACVH_V ADI_V ADO_V TEST5_V Ver:4 D C B A 10/06/25 29 v2.3 + ES51950(5000counts) Dual Display/Cap 4.2 EEPROM is used (AC AVG circuit) 0 ~ 100pF + 1 + 10K C7 R33 IVSL IVSH ADP ACVH_A 10nF ADI_A C1 VRH_A 100K 100K 100K 0 470K 220nF 220nF 220nF VRH 100nF R3 R4 R5 R10 R11 C10 C11 C15 C16 ADO_A ADI_A TEST5A ACVLA ACVHA CSH+ CSHVAIVSL IVSH ADP RAZ_A BUF_A CAZ_A CINT_A CLN_A CLP_A VRH CLP_V CLN_V CINT_V CAZ_V BUF_V RAZ OHMC4 OHMC3 OHMC2 OHMC1 VR_A DACAO VR DACVO OR1 VR5 VR4 VR3 VR2 OVSG 2 V+ V- C25 + 220pF DIS_DCA DIS_DGBP DIS_LPF ALARM1 TSEL CESEL R29 3 CAL_nF APOSEL SVR S50V C_clamp Opt_nF LCDCAP OSC2 OSC1 BKOUT BZOUT ALARM BP1 BP2 BP3 BP4 SEG01 SEG02 SEG03 SEG04 SEG05 SEG06 SEG07 SEG08 SEG09 SEG10 SEG11 SEG12 SEG13 SEG14 SEG15 SEG16 SEG17 SEG18 SEG19 SEG20 SEG21 SEG22 200 C29 U1 102 101 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 ES51950 2.2uF APOSEL SVR S50V C_clamp Option_nf C4 BKOUT BZOUT ALARM BP1 BP2 BP3 BP4 SEG01 SEG02 SEG03 SEG04 SEG05 SEG06 SEG07 SEG08 SEG09 SEG10 SEG11 SEG12 SEG13 SEG14 SEG15 SEG16 SEG17 SEG18 SEG19 SEG20 SEG21 SEG22 C1815 V- BZOUT Q10 C1815 1 J4 4MHz 0.1uF Y1 R25 2.2K PTC Q9 BKLIT HOLD 4 BKOUT D3 LED SW15 SW14 SW13 SW12 SW11 SW3 SW2 SW8 SW7 SW6 SW5 R30 10K RANGE SEL S50V SVR SAC FC4 FC3 FC2 FC1 Fin R6 100K R9 V- Q12 KN2907 BKLIT HOLD V- RANGE SEL S50V SVR SAC FC4 FC3 FC2 FC1 100 VQ11 C1815 V- BZ1 Buzzer R31 10K Hi-Z ALARM D1 LED 5 VR4 VR3 ALARM1 D2 LED C30 22uF TRMS Circuit ADI_A + VS C21 + - VS C20 10uF C32 22uF 10uF C36 + + VS 10uF ADI_V C35 - VS 10uF R1 100K R7 R8 R2 100K 200 + VS R35 200 R37 + VS Title B Size 100 100 - VS 200K - VS 200K V- V- 1 2 3 4 5 6 7 1 2 3 4 5 6 7 Q1 C1815 Q2 C1815 U2 C31 R36 10K 10K 6 SW1 Power Switch 5.6V 0.1uF + + 6 Revision V- Ver:4 ACVH_V ACVH_A ZR2 7.5V V+ 0.1uF 10uF 10uF Bat- C6 + VS + VS 200 R41 14 13 12 11 10 9 8 200 R38 14 13 12 11 10 9 8 C5 C9 C8 ZR1 Bat+ DC3.0V 3.3uF 500K 3.3uF - VS Vin + VS En NC - VS NC CAV NC dB COMMON BUF out RL BUF in Iout ES636 C33 VR5 + VS U3 R40 500K - VS Vin + VS En NC - VS NC CAV NC dB COMMON BUF out RL BUF in Iout ES636 VR7 + VS Sheet of Drawn By: ES51950_RMS Circuit 20-Nov-2009 F:\Protel file\KA030.ddb Number + C27 Q8 C1815 + 1uF R21 9K 2K 2K C26 Close to IC Q7 C1815 Date: File: + 27K 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 10M Detailed C22 R20 1K R27 R28 C1815 5 + 4.7uF 220nF 220nF 360K 120K 22n 47n 220nF 470n VRH_A VRH_V 100 1K 10.0K 101K 1.111M Vin Gnd 50K Q5 C1815 Q6 4 + Metallized Polypropylene Film Capacitor : C11, C12 VR1 R22 27K VRH_A 10K VRH_V Detailed C12 C13 R12 R13 C17 C18 C14 C19 R14 R15 R16 R17 R18 180K R19 Bottom Ground Plane SW10 ACV RMS VR1 1 J1 1 J2 R26 VR6 C1815 3 + D C VR2 R32 27K SW9 SW_RC R23 2.2K PTC R24 2.2K PTC Q3 C1815 Q4 2 4.7nF 2.2uF FC1 FC2 FC3 FC4 SAC RANGE HOLD SEL BKLIT 39 40 41 42 43 44 45 46 C3 470nF 47 48 49 50 51 52 C23 1nF 53 C24 220pF 54 55 56 57 SLEEP 58 BUZIN 59 60 61 62 63 SEG24 64 SEG23 C28 C34 2.2uF C37 LBAT9 C2 470nF 128 127 126 125 124 123 122 121 120 119 118 117 116 115 114 113 112 111 110 109 108 107 106 105 104 103 AGND AGND DGND V+ V+ VVLBAT9 C+ CFC1 FC2 FC3 FC4 SAC RANGE HOLD SEL BKLIT NC DISDCA DISDGB DIS_LPF ALARM1 TSEL CESEL VR1 ACVL_V ACVH_V ADI_V ADO_V TEST5V SGND CACA+ R9K R1K OVX OVH OVH1 LPC1 LPC2 LPC3 LPFOUT SLEEP BUZIN FREQ CAL_EN SDA SCL SEG24 SEG23 ACVH_V ADI_V D C B A 10/06/25 30 v2.3 B A 1 + ES51950(5000counts) Dual Display/Cap 4.3 EEPROM is not used (AC RMS circuit) 0 ~ 100pF 0 ~ 100pF + + 1 + 10K C7 R33 IVSL IVSH ADP 27K C1 VRH_A 100K 100K 100K 0 470K 220nF 220nF 220nF ADO_A ADI_A TEST5_A ACVL_A ACVH_A 10nF VRH 100nF R3 R4 R5 R10 R11 C10 C11 C15 C16 ADO_A ADI_A TEST5A ACVLA ACVHA CSH+ CSHVAIVSL IVSH ADP RAZ_A BUF_A CAZ_A CINT_A CLN_A CLP_A VRH CLP_V CLN_V CINT_V CAZ_V BUF_V RAZ OHMC4 OHMC3 OHMC2 OHMC1 VR_A DACAO VR DACVO OR1 VR5 VR4 VR3 VR2 OVSG 2 V+ V- C27 C25 DIS_DCA DIS_DGBP DIS_LPF ALARM1 TSEL CESEL R29 3 CAL_nF APOSEL SVR S50V C_clamp Opt_nF LCDCAP OSC2 OSC1 BKOUT BZOUT ALARM BP1 BP2 BP3 BP4 SEG01 SEG02 SEG03 SEG04 SEG05 SEG06 SEG07 SEG08 SEG09 SEG10 SEG11 SEG12 SEG13 SEG14 SEG15 SEG16 SEG17 SEG18 SEG19 SEG20 SEG21 SEG22 200 C29 U1 102 101 100 99 98 97 96 95 94 93 92 91 90 89 88 87 86 85 84 83 82 81 80 79 78 77 76 75 74 73 72 71 70 69 68 67 66 65 ES51950 2.2uF APOSEL SVR S50V C_clamp Option_nf C4 + Q9 C1815 V- BZOUT Q10 C1815 1 J4 4MHz 0.1uF Y1 R25 2.2K PTC BKOUT BZOUT ALARM BP1 BP2 BP3 BP4 SEG01 SEG02 SEG03 SEG04 SEG05 SEG06 SEG07 SEG08 SEG09 SEG10 SEG11 SEG12 SEG13 SEG14 SEG15 SEG16 SEG17 SEG18 SEG19 SEG20 SEG21 SEG22 Q8 C1815 BKLIT HOLD 4 BKOUT D3 LED SW15 SW14 SW13 SW12 SW11 SW3 SW2 SW8 SW7 SW6 SW5 R30 10K RANGE SEL S50V SVR SAC FC4 FC3 FC2 FC1 Fin R6 100K R9 V- Q12 KN2907 BKLIT HOLD V- RANGE SEL S50V SVR SAC FC4 FC3 FC2 FC1 100 VQ11 C1815 V- BZ1 Buzzer R31 10K Hi-Z ALARM D1 LED ALARM1 D2 LED 10K Average Circuit VR3 + C20 1uF R34 15K D4 1N4148 VR4 + C31 10K 1N4148 1uF R39 15K D6 5 R1 100K R7 R8 R2 100K ADO_V D5 100 100 R36 1N4148 R41 V- V- 10K C21 1uF 10K C32 1uF Q1 C1815 Q2 C1815 C30 4.7uF R37 15K 56K R38 56K R43 C33 4.7uF R42 15K 56K R44 56K R45 Bat+ DC3.0V ZR1 C8 6 SW1 10uF Power Switch 5.6V 0.1uF 6 Revision V- Ver:4 ZR2 7.5V V+ 0.1uF 10uF Bat- C6 C5 C9 TEST5_V ADI_V ACVH_V ACVL_V C34 0.1uF TEST5_A ADI_A ACVH_A ACVL_A C35 0.1uF Sheet of Drawn By: ES51950_AVG Circuit 20-Nov-2009 F:\Protel file\KA030.ddb Number 1N4148 D7 ADO_A Title B Size Date: File: + 1uF R21 9K 2K 2K C26 220pF Close to IC Q7 C1815 5 + 4.7uF 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 C22 Detailed C1815 R20 1K R27 R28 Q6 4 + VRH_A 10K VRH_V 220nF 220nF 360K 120K 22n 47n 220nF 470n VRH_A VRH_V 100 1K 10.0K 101K 1.111M Q5 C1815 50K 10M Bottom Ground Plane Gnd Vin R19 180K Detailed C12 C13 R12 R13 C17 C18 C14 C19 R14 R15 R16 R17 R18 VR1 1 J1 1 J2 R26 VR5 C1815 3 + Metallized Polypropylene Film Capacitor : C11, C12 VR1 R22 27K VR2 R32 27K SW9 SW_RC R23 2.2K PTC R24 2.2K PTC Q3 C1815 Q4 2 + D C B A 1 FC1 FC2 FC3 FC4 SAC RANGE HOLD SEL BKLIT 4.7nF ACVL_V ACVH_V ADI_V ADO_V TEST5_V D C B A 10/06/25 31 v2.3 LBAT9 C2 470nF 128 127 126 125 124 123 122 121 120 119 118 117 116 115 114 113 112 111 110 109 108 107 106 105 104 103 AGND AGND DGND V+ V+ VVLBAT9 C+ CFC1 FC2 FC3 FC4 SAC RANGE HOLD SEL BKLIT NC DISDCA DISDGB DIS_LPF ALARM1 TSEL CESEL VR1 ACVL_V ACVH_V ADI_V ADO_V TEST5V SGND CACA+ R9K R1K OVX OVH OVH1 LPC1 LPC2 LPC3 LPFOUT SLEEP BUZIN FREQ CAL_EN SDA SCL SEG24 SEG23 39 40 41 42 43 44 45 46 C3 470nF 47 48 49 50 51 52 C23 1nF 53 C24 220pF 54 55 56 SLEEP 57 BUZIN 58 59 60 61 62 SEG24 63 SEG23 64 C28 + ES51950(5000counts) Dual Display/Cap 4.4 EEPROM is not used (AC AVG circuit) 0 ~ 100pF 0 ~ 100pF + ES51950(5000counts) Dual Display/Cap 5. Package Information 8.1 128L LQFP Outline drawing 8.2 Dimension parameters v2.3 32 10/06/25