FcallBox MULTIMETER MODULE

Description

This board used into the FCALLBOX universal measurement system has Voltmeter, Ampemeter in DC and AC RMS functions with a high precision.

It includes 2 modules.

The characteristics are :

-Voltmeter auto-range , auto polarity DC and AC true RMS (range can be changed by resistor adjustment).

**Precision Voltmeter in DC**
Range	Precision
0.5V to 150V	+0.06% / -0.10%
0.1V to 4V	+0.37% / -0.11%
0.02V to 0.5V	+0.4% / -0.44%
10mV	2%

**Precision Voltmeter in AC**
Range	Precision
1KH to 50KHz	15%
500Khz	40%
1KHz from 10mV to 4V	+1%/-4%
10mV	2%

- Amperemeter 5A or more or other by hardware configuration, DC or AC true RMS (but the voltmeter is not available in current AC mode)

**Amperemeter Precision for 5A version (ACS712)**
Range	Precision
0.1A to 3.7A	+0.5% / -0.5%
20mA	4%

**Amperemeter Precision for 1A version (R = 2 Ohms)**
Range	Precision
0.1A to 1A	+0.5% / -0.5%
20mA	2%

- Temperature sensor for measurements tracability.

- Note : plug COM is common for U and I.

- Calibration by PC.

- The PC software has a socket server to allow remote control of the module (for eg to script measurements or to use remotly the module by a mobile...)

- dimensions PCB : 100x50mm

BLOC DIAGRAM

Schematic

Download the schematic here

Bill of material

**Top view**
Ref	Description	Vendor / reference
R73,R75,R83,R85,R93,R94,R95,R96,R97,R98,R104,R105,R106,R107,R108,R109	Resistor 100K 1% 0603	All brand
R99,R100,R110,R111	Resistor 27K 1% 0603	All brand
R71,R72,R81,R82	Resistor 180K 1% 0603	All brand
R69,R70,R79,R80	Resistor 10K 1% 0603	All brand
R89,R92 NE	Resistor 10K 1% 0603	All brand
R5,R38	Resistor 39K 1% 0603	All brand
R74,R76,R84,R86	Resistor 9K1 1% 0603	All brand
R66,R68,R77,R78	Resistor 4.7M 1% 0603	All brand
R115,R116,R119,R120	Resistor 4.7M 1% 1206	All brand
R88,R91	Resistor 100R 1% 0603	All brand
R12,R40	Resistor 1KR 5% 0603	All brand
R41,R42,R54,R55,R56,R57,R58	Resistor 4.7K 5% 0603	All brand
C27,C29,C47,C48,C49,C50,C52,C53,C56,C57,C58,C60,C61,C68,C69,C70,C71,C72,C73,C74,C75,C76,C79,C80,C81,C113	Capacitor 100nF 50V X7R 0603	All brand
C106,C107,C108,C109 NE	Capacitor 1nF 50V X7R 0603	All brand
C112	Capacitor 10nF 50V X7R 0603	All brand
C87,C88,C89,C90,C91,C93,C94,C95,C97,C98,C99,C100,C101,C103,C104,C105,C110,C111	Capacitor 10uF 10V X7R 0603	All brand
D8,D14	Diode schottky SDO323 BAS416	NXP
U27	Voltage reference 2.5V SOT23	MCP1525T-I/TT Microchip
U31,u32	74HC4052 SO16	All brand
U9,U10,U15,U16	AOP OPA2197 SOIC8	BOURNS , TI
U29,U30 non mounted	current sensor ACS712ELCTR-05B-T (5A) SOIC8	Alegro Microsystem ACS712ELCTR-05B-T
U18	IC ADC 18bits MCP3422A0-E/SN	Maxim MCP3422A0-E/SN
U17	IC ADC 18bits MCP3422A0-E/SN or MCP3422A1-E/SN SOIC-8	Maxim MCP3422A0-E/SN ou MCP3422A1-E/SN
U37,U38	74HC4053 SO16	All brand
U33,U34 not mounted	EEPROM 24C32 SO8	All brand
U19,U20	IC ICL7660 SO8	Intersil CL7660CBAZ or equivalent
U35,U36	RMS converter AD736 SO8	AD736 Analog Device
U39	Temperature sensor TCN75A SO8	TCN75AVOA Microchip
U25,U26	I2C isolator ISO1541D	ISO1541D TEXAS INSTRUMENTS
U21,U22	IC PCF8574A TSSOP20	PCF8574TS NXP or PCF8574PWRE4 TEXAS INSTRUMENTS
U23,U24	DC DC isolated 5V to 5V	RECOM RBE-0505S
U41	Circuit intégré LDO 3.3V 500mA SOT23-5	SPX3819M5-L-3-3 ou MIC5504-3.3YM5-TRS
J2	Connector male right angle 2x19 pitch 2.54mm	All brand

**Bottom view**
Ref	Description	Vendor / reference
R117,R118,R121,R122	inductor 22uH 140mA 1210	EPCOS B82422A1223K10 or equivalent
R43,R44,R45	Resistor 4K7 5% 0603	All brand
R112,R113,R101,R102 NE	Resistor 100K 1% 0603	All brand
R103,R114	Resistor 100K 1% 0603	All brand
R87,R90	Resistor 100R 5% 0603	All brand
C23,C24,C25,C26,C28,C51,C54,C55,C59,C63,C64,C65,C66,C67,C78,C82,C83,C107,C85,C62	Capacitor 100nF 50V X7R 0603	All brand
C86,C92,C96,C102	Capacitor 10uF 16V X7R 0603	All brand
D3,D4,D5,D6,D7,D9,D10,D11,D12,D13	Diode schottky SDO323 BAS416	NXP