LT6650 UUUPI FU CTIO SFB (Pin 1): Resistor Divider Feedback Pin. Connect a IN (Pin 4): Positive Supply. Bypassing with a 1µF capacitor resistor divider from OUT to GND and the center tap to FB. is recommended if the output loading changes. This pin sets the output potential. OUT (Pin 5): Reference Output. The output sources and GND (Pin 2): Ground Connection. sinks current. It is stable with any load capacitor with a DNC (Pin 3): Do not connect. Connected internally for post total capacitance of 1µF or more. Higher load capacitance package trim. This pin must be left unconnected. improves load transient response. WBLOCK DIAGRA IN 4 LT6650 VR = 400mV + REFERENCE 5 OUT – DNC 3 1 FB 2 6650 BD GND UUWUAPPLICATIO S I FOR ATIOLong Battery Life functions. Output impedance can be reduced by DC load- ing of the output by 40µA to 200µA, and/or adding an R The LT6650 is a micropower, adjustable reference which Z to the output capacitor for a 100µs time constant as shown operates from supply voltages ranging from 1.4V to 18V. in Figure 1 and the Typical Performance Characteristics The series regulated output may be configured with exter- graphs. nal resistors to any voltage from 400mV to nearly the supply potential. Under no-load conditions, the LT6650 The LT6650 Voltage reference should have an input by- dissipates only 8µW when operating on a 1.4V supply. pass capacitor of 0.1µF or larger. When the circuit is Other operating configurations allow the LT6650 to be used as a micropower positive or negative adjustable R shunt reference from 1.4V to 18V. IN IN OUT V 4 5 V IN OUT Bypass and Load Capacitor CIN LT6650 CL FB 1 The LT6650 voltage reference requires a 1µF or greater RZ output capacitance for proper operation. This capacitance 2 6650 F01 GND may be provided by either a single capacitor connected between OUT and GND or formed by the aggregate of several capacitors that may be serving other decoupling Figure 1. LT6650 Input-Output Configuration 6650fa 7