ELM842B CMOS Low power operational amplifier ■General description ELM842B is low voltage and low power CMOS single operational amplifier which makes it easy to design circuits and operates from a 1.2V single power source. As for power supply voltage, ELM recommends to use within the range of 1 . 2 V to 5 . 5 V. The consumption current of ELM842B is low; on the other hand, since the output stage of ELM842B is class A operation drive, ELM842B is able to provide current supply of 90μA(Typ. At Vdd=1.5V). ELM842B is suitable for signal process of applications which require low power. ■Features ■Application • • • • • • • Battery-operated portable devices • Signal process in low power circuit • Low voltage analog circuit Operation from a single power source Input available within the range of power supply voltage Low voltage operation : 1.2V≤Vdd≤5.5V Low current consumption : Typ.130μA(Vdd=1.5V) Unity gain bandwidth : Typ.1.0MHz(Vdd=1.5V) Package : SOT-25 ■Maximum absolute ratings Parameter Power supply voltage Input voltage Differential input voltage Output voltage Output short circuit Power dissipation Operating temperature Storage temperature Symbol Vdd Vin Vid Vout Limit 10 Vss-0.3 to Vdd+0.3 Vdd-Vss Vss-0.3 to Vdd+0.3 Continuous 300 -30 to +80 -55 to +125 Pd Top Tstg * When power supply voltage is below 5.0V, short of output terminal will do no damage to the IC. When power supply voltage is above 5.0V, it may cause short of VDD and result in reliability damage of the IC. Unit V V V V Sec.* mW °C °C ■Suggested operating condition Parameter Power supply voltage Operating temperature Symbol Vdd Top Min. 1.2 -20 Typ. Max. 5.5 +70 ■Selection guide ELM842B-x Symbol a b Product version Taping direction SOT-25(TOP VIEW) 5 4 + 1 2 3 ELM842 B - x ↑ ↑ a b B S, N: Refer to PKG file ■Pin configuration Unit V °C ■Standard circuit Vin Pin No. 1 2 3 4 5 Pin name OUT VDD IN+ INVSS 4-1 + ELM842B 200k� 22k� Vout ELM842B CMOS Low power operational amplifier ■Electrical characteristics Vdd=1.5V Parameter Input offset voltage Input bias current Common-mode input voltage range Maximum output voltage swing Maximum output source current Open-loop gain Common-mode rejection ratio Supply voltage rejection ratio Current consumption Unity gain bandwidth Slew rate Vdd=3.0V Parameter Input offset voltage Input bias current Common-mode input voltage range Maximum output voltage swing Maximum output source current Open-loop gain Common-mode rejection ratio Supply voltage rejection ratio Current consumption Unity gain bandwidth Slew rate Symbol Vio Iib Vcmr Vouts Isource Avd CMRR PSRR Iss GBW SR Symbol Vio Iib Vcmr Vouts Isource Avd CMRR PSRR Iss GBW SR Condition Vout=Vdd/2 Vid=100mV, RL=200kΩ Vid=100mV Vout=300mV, RL=200kΩ Min. 0.08 1.42 40 Vout=Vdd/2, No-load RL=200kΩ, CL=20pF Condition Vout=Vdd/2 Vid=100mV, RL=200kΩ Vid=100mV Vout=300mV, RL=200kΩ 0.45 Min. 0.04 2.80 45 Vout=Vdd/2, No-load RL=200kΩ, CL=20pF 0.45 Vss=0V, Top=25°C Typ. Max. Unit 10 mV 1 nA 1.45 V V 90 μA 75 dB 75 dB 75 dB 130 310 μA 1 MHz 1.00 V/μs Vss=0V, Top=25°C Typ. Max. Unit 10 mV 1 nA 2.90 V V 100 μA 80 dB 85 dB 80 dB 145 360 μA 1 MHz 1.00 V/μs ■Marking SOT-25 � � � Symbol a b c 4- 2 Mark C 0 to 9 0 to 9 Content ELM842B Lot No. Lot No. ELM842B CMOS Low power operational amplifier ■Note 1) Load resistance ELM842B is designed for low power consumption applications; hence, the output source current is only 90μA (Typ. at Vdd=1.5V). As a result, ELM842B is not able to maintain output voltage swing when trying to drive small load resistance. Considering this, load and feedback resistance for ELM842B should be selected carefully. ELM recommends the following operating temperature range. < Power supply voltage > < total resistance value of load/feedback resistor > Vdd≤5.5V : R≥250kΩ Vdd≤3.6V : R≥200kΩ Vdd≤1.8V : R≥150kΩ 2) Operation from single power source ELM842B is designed to be most suitable for single power source; therefore, ELM842B is able to share power supply with logic circuit one. Meanwhile, ELM842B can also operate from double power sources .To protect power supplies of ELM842B and logic circuit from noise, please separate wire from power supply and use decoupling (bypass) capacitor. Using the capacitor can improve PSRR characteristics, especially on 10kHz to 100kHz or more. 3) Feedback When OP-AMP circuit is used with feedback resistor, oscillation may happen in the circuit with loop-gain like unity gain follower. a) When large feedback resistance is used, the phase margin is decreased by its combination with the parasitic capacitance of the input part of OP-AMP. In this situation, please connect small capacitor parallelly with feedback resistor as shown in fig-1. b) For capacitive load, external resistor in series connection will be effective as shown in fig-2. c) Being used as an unity gain follow, ELM842B is able to drive capacitive load of 100pF directly without oscillation. 4) Operation at Vdd<1.2V ELM842B is able to maintain operation when supply voltage is below 1.2V (Vdd≥1.2V) since all input voltage is acceptable within the range of power supply voltage. However, AC characteristics will become weak under this situation because of the decrease of bias current in the IC. For further information, please contact ELM. a) fig-1 ��� b) fig-2 ��� � ���� ������� ���� ������� � � � �� �� 4- 3 ELM842B CMOS Low power operational amplifier ■Typical characteristics 102 SINK CURRENT - Vdd 180 160 140 120 100 80 60 40 101 100 10-1 20 0 200 1 2 3 4 Vdd (V) 5 10-2 0 6 SOURCE CURRENT - Top 1 2 5 100 Vdd=1.5V 4 4 RL=47k� 2 RL=20k� 1 10 20 30 40 50 60 70 0 Top (�) Iss - Vdd 200 6 3 50 -20 -10 0 5 RL=100k� 150 Vdd=3V 3 Vdd (V) Vout - Vdd 6 Vout(V) SOURCE CURRENT (�A) SOURCE CURRENT - Vdd SINK CURRENT (mA) SOURCE CURRENT (�A) 200 1 250 2 3 Vdd (V) 4 5 6 Iss - Top 180 160 200 120 Iss (�A) Iss (�A) 140 100 80 60 20 Av (dB) Vdd=1.5V No Load 1 2 3 Vdd (V) 4 5 -20 -10 0 6 Av -FREQ 100 90 80 70 60 50 40 30 20 10 0 -10 101 150 100 40 0 Vdd=3V Vdd=1.5V 102 103 104 105 FREQ (Hz) 106 107 4- 4 10 20 30 40 50 60 70 Top (�)