Datasheet MAX6078A, MAX6078B (Maxim) - 10

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Detailed Description Wideband Noise Reduction (NR)
To improve wideband noise and transient power supply noise, connect a 0.01µF capacitor from NR to GND (see the Typical Operating Characteristics). Larger values do not appreciably improve noise reduction. A 0.01µF capacitor reduces the spectral noise density at 100Hz from 580nV/√Hz to 385nV/√Hz for the 2.5V output version. Noise at the input pin can affect output noise, but can be reduced by connecting an optional bypass capacitor between IN and GND, as shown in Figure 1. OUTF SUPPLY IN LOAD OUTS MAX6078 EN NR GND 0.01µF* * OPTIONAL Figure 1. Noise Reduction Capacitor
Output Bypassing
Use an output capacitor with a value between 0.1μF and 4.7µF. Place the output capacitor as close to OUTF as possible. For applications driving switching capacitive loads or rapidly changing load currents, use a 0.1μF capacitor in parallel with a larger load capacitor to reduce equivalent series resistance (ESR). Larger capacitor values and lower ESR reduce transients on the reference output.
Turn-On Time
These references typically turn on and settle to within 0.1% of their final value in 5ms with no capacitive loads at NR pin. A 0.1µF load capacitor at OUTF and a 0.01µF noise reduction capacitor connected to the NR input increase the turn-on time to approximately 50ms.
Output Force and Sense
These references provide independent connections for the force output (OUTF), which supplies current to the load and the feedback input that regulates the load voltage through the output sense pin (OUTS). This configuration allows for the cancellation of the voltage drop on the lines connecting the reference to the load. Connect OUTF to the load and connect OUTS to OUTF at the point where the voltage accuracy is needed (Figure 1).
Shutdown
Although the operating power supply current of these references is very low, there are some cases that require even lower supply current during shutdown conditions. Pulling EN low disables the output with an internal resistive load to ground and forces the quiescent current to less than 100nA. Pulling EN high enables normal operation. The return to normal operation occurs within the 3ms enable time delay typically.
Thermal Hysteresis
Thermal hysteresis is the change of output voltage at TA = +25°C before and after the device is cycled over its entire operating temperature range. The typical thermal hysteresis value is 20ppm. www.maximintegrated.com Maxim Integrated | 10 Document Outline General Description Applications Benefits and Features Simplified Block Diagram Absolute Maximum Ratings Package Information 8 TDFN 8 WLP Electrical Characteristics – 2.5V Typical Operating Characteristics Pin Configurations 6 WLP 8 TDFN-EP Pin Description Functional Diagram Typical Operating Circuit Detailed Description Wideband Noise Reduction (NR) Output Bypassing Turn-On Time Output Force and Sense Shutdown Thermal Hysteresis Applications Information Precision Current Source Ordering Information Revision History