Datasheet MIC7300 (Microchip) - 9

MIC7300 Micrel the phase lag caused by feedback resistor R and input V+ FB 2.2V to 10V capacitance C . The value of C is determined by first IN FB estimating C and then applying the following formula: 3 5
MIC7300
IN VIN 0V to V+ 1 V R × C ≤ R × C OUT IN IN FB FB 4 0V to V+ 2 CFB VOUT = VIN RFB
Figure 4. Voltage Follower/Buffer
RIN VIN VOUT C VS IN 0.5V to Q1 VCEO(sus) VOUT V+ 0V to V+ 2.2V to 10V
Figure 2. Cancelling Feedback Phase Lag
Load 3 5 V
MIC7300
IN I Since a significant percentage of C may be caused by board OUT 1 IN 0V to 2V layout, it is important to note that the correct value of C may 4 Q1 FB V 2 2N3904 CEO = 40V { change when changing from a breadboard to the final circuit IC(max) = 200mA layout. RS 10 Change Q1 and R Ω
Typical Circuits
S 1⁄2W for higher current and/or different gain. Some single-supply, rail-to-rail applications for which the VIN MIC7300 is well suited are shown in the circuit diagrams of I = = 100mA/V as shown OUT RS Figures 3 through 7. V+
Figure 5. Voltage-Controlled Current Sink
2.2V to 10V R4 V 3 5
MIC7300
IN 100k 1 C1 V + VOUT V+ 0V to 0.001µF 4 0V to V+ AV 2 4 5
MIC7300
1 R2 VOUT 3 V+ 910k 2 0V R1 100k R2 R4 V+ 100k 100k R3
Figure 3a. Noninverting Amplifier
100k 100 V+
Figure 6. Square Wave Oscillator
CIN R1 R2 (V) 33k 330k OUT R2 V A = 1+ ≈ 10 V+ V R1 4 5
MIC7300
COUT VOUT 1 0V 3 0 2 RL 0 100 V (V) IN R3
Figure 3b. Noninverting Amplifier Behavior
V+ R2 330k 330k A = − = = 10 − C1 R4 V R1 33k 1µF 330k
Figure 7. AC-Coupled Inverting Amplifier
June 2005 9 MIC7300