LT6604-15 PIN FUNCTIONS+INA and –INA (Pins 2, 4): Channel A Input Pins. Signals 14 can be tied to Pin 8 on the PC board. Pin 14 should can be applied to either or both input pins through identi- be bypassed with a 0.01μF ceramic capacitor unless it is cal external resistors, RIN. The DC gain from differential connected to a ground plane. inputs to the differential outputs is 536Ω/RIN. V+A and V+B (Pins 25, 17): Positive Power Supply Pins VOCMA (Pin 6): DC Common Mode Reference Voltage for Channels A and B. For a single 3.3V or 5V supply (Pins for the 2nd Filter Stage in Channel A. Its value programs 7, 24, 31, 32 and 35 grounded) a quality 0.1μF ceramic the common mode voltage of the differential output of bypass capacitor is required from the positive supply pin the fi lter. Pin 6 is a high impedance input, which can be (Pins 25, 17) to the negative supply pin (Pins 7, 24, 31, driven from an external voltage reference, or Pin 6 can be 32 and 35). The bypass should be as close as possible to tied to Pin 34 on the PC board. Pin 6 should be bypassed the IC. For dual supply applications, bypass the negative with a 0.01μF ceramic capacitor unless it is connected to supply pins to ground and Pins 25 and 17 to ground with a ground plane. a quality 0.1μF ceramic capacitor. V– (Pins 7, 24, 31, 32, 35): Negative Power Supply Pin +OUTB and –OUTB (Pins 19, 21): Output Pins. Pins 19 and (can be ground). 21 are the fi lter differential outputs for channel B. With a typical short-circuit current limit greater than ±40mA each VMIDB (Pin 8): The VMIDB pin is internally biased at mid- pin can drive a 100Ω and/or 50pF load to AC ground. supply, see Block Diagram. For single supply operation the VMIDB pin should be bypassed with a quality 0.01μF +OUTA and –OUTA (Pins 27, 29): Output Pins. Pins 27 and ceramic capacitor to ground. For dual supply operation, 29 are the fi lter differential outputs for channel A. With a Pin 8 can be bypassed or connected to a high quality DC typical short-circuit current limit greater than ±40mA each ground. A ground plane should be used. A poor ground pin can drive a 100Ω and/or 50pF load to AC ground. will increase noise and distortion. Pin 8 sets the output V common mode voltage of the 1st Filter Stage in channel B. MIDA (Pin 34) : The VMIDA pin is internally biased at mid- supply, see Block Diagram. For single supply operation It has a 5.5kΩ impedance, and it can be overridden with the V an external low impedance voltage source. MIDA pin should be bypassed with a quality 0.01μF ceramic capacitor to ground. For dual supply operation, +INB and –INB (Pins 10, 12): Channel B Input Pins. Signals Pin 34 can be bypassed or connected to a high quality DC can be applied to either or both input pins through identi- ground. A ground plane should be used. A poor ground cal external resistors, RIN. The DC gain from differential will increase noise and distortion. Pin 34 sets the output inputs to the differential outputs is 536Ω/RIN. common mode voltage of the 1st stage fi lter stage in chan- nel A. It has a 5.5kΩ impedance, and it can be overridden VOCMB (Pin 14): Is the DC Common Mode Reference with an external low impedance voltage source. Voltage for the 2nd Filter Stage in Channel B. Its value programs the common mode voltage of the differential Exposed Pad (Pin 35): V–. The Exposed Pad must be output of the fi lter. Pin 14 is a high impedance input, which soldered to the PCB. can be driven from an external voltage reference, or Pin 660415fb 7