Flame Detection Amplifier MM1217 MITSUMI Flame Detection Amplifier Monolithic IC MM1217 Outline This IC is comprised of an operation amplifier, a comparator, and a reference power source. It is worthy of note that the input offset voltage and the input offset voltage temperature drift of this operation amplifier are one digit less than those of conventional products regardless of the single power supply. Formerly, offset voltage adjustment was required for flame detection using a thermocouple on gas appliances, but with this IC adjustment is not required. Due to the single power supply, low current consumption, and low offset voltage, two batteries can be used for operation, making it appropriate for equipment that amplifies the very small signal of portable equipment. Features General 1. Power supply voltage (single batteries) 2. Current consumption 3. Power supply line elimination ratio VCC=1.8V~6V (It is available to operate by two dry cell batteries.) 0.1mA typ. 60dB typ. Amplifier section 1. Low input offset voltage 2. Low input offset voltage drift (-20°C~+75°C) 3. Input offset current 4. Input bias current 5. Gain (Open roop) ±0.1mV typ. ±1.0µV/°C typ. 1nA typ. 50nA typ. 100dB typ. Comparator Section 1. Input offset voltage 2. Low input offset voltage drift (-20°C~+75°C) 3. Input bias current 4. Output sink current ±1.0mV typ. ±10µV/°C typ. ±25nA typ. 5mA min. Reference Voltage Section 1. Reference voltag 2. Reference voltage temperature characteristics 3. Output current 1.27V±0.05V ±100ppm/°C typ. 0.3mA min. Package SOP-8C (MM1217XF) SIP-9A (MM1217XS) Applications 1. Gas burners 2. Instantaneous gas water heaters Flame Detection Amplifier MM1217 MITSUMI Pin Assignment MM1217XF 8 7 1 2 6 3 5 4 SOP-8C MM1217XS 1 2 3 4 5 6 7 8 9 SIP-9A Pin Function Pin Function Pin No. MM1217XF MM1217XS 1 AIN+ AIN+ 2 AIN- AIN- 3 AOUT AOUT 4 GND COMPIN+ 5 COMPIN- GND 6 VS COMPIN- 7 COMPOUT VS 8 VCC COMPOUT 9 - VCC (SOP-8C) Pin No. Pin Function Internal Equivalent Circuit Pin No. Pin Function 1 AIN+ 5 COMPIN- 2 AIN- 6 VS 3 AOUT 7 COMPOUT Internal Equivalent Circuit Flame Detection Amplifier MM1217 MITSUMI Block Diagram MM1217XF MM1217XS Absolute Maximum Ratings (Ta=25°C) Item Symbol Specification Units Storage temperature TSTG -40~+125 °C Operating temperature TOPR -20~+75 °C Power supply voltage VCC max. -0.3~+10 V Input voltage VIN -0.3~+10 V Allowable power dissipation Pd Electrical Characteristics MM1217XF 300 MM1217XS 470 mW (Unless otherwise specified Ta=25°C, VCC=3V, VIN=0V) Item Symbol Current consumption ICC Reference voltage output current IOVS1 0.3 Reference voltage VS1 1.22 Reference voltage temperature drift Measurement Conditions Min. Typ. Max. Units 0.1 VS1 mA 1.27 1.32 V ppm/°C 50 60 dB 3.0 PSRR Power supply voltage range VCC 1.8 Input voltage range VI -0.2 Input offset voltage VIOA temperature drift mA ±100 Power supply line elimination ratio Input offset voltage f=100Hz 0.15 6.0 V 0.3 V ±0.1 ±0.35 mV VIOA ±1.0 ±3.0 µV/°C Amplifier Input offset current IIOA 1 10 nA section Input bias current IBA 50 150 nA Gain GV RL=100kΩ 80 Output current IOA VIN=10mV, VO1=0.5V 0.5 Output voltage VOA VIN=-5~25mV RL=10kΩ 0.01 100 dB mA VCC -1.0 V Flame Detection Amplifier MM1217 MITSUMI Electrical Characteristics Unless otherwise specified (Ta=25°C, VCC=3V, VIN=0V) Item Symbol Measurement Conditions VIOC VIN=-5mV ±1.0 ±3.5 VIOC VIN=-5mV ±10 ±30 µV/°C Input bias current IBC VIN=-5mV 25 75 Output sink current ISINK VIN=10mV, VO2=0.4V Output leak current ILC VO2=VCC+1V Output saturation voltage ISAT VIN=10mV, ISINK=5mA Input offset voltage Input offset voltage Comparator Section temperature drift Min. Typ. Max. Units 5 mV nA mA 200 0.2 µA 400 mV Note 1 : Amplifier output ··· emitter-follower (pull-down resistance 22kΩ) Note 2 : Comparator output ··· open collector Application Circuits Flame detection circuit using a thermocouple (single power source) Note : Use a gain range of 20dB-50dB in the amplifier section (40dB recommended) . Also, insert the capacitor between output 3 and GND instead of parallel to R2 in order to eliminate noise from the input. Please note that use of the equipment under different conditions will cause vibration.