LM2696EVAL National Semiconductor, LM2696EVAL Datasheet
LM2696EVAL
Specifications of LM2696EVAL
Related parts for LM2696EVAL
LM2696EVAL Summary of contents
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... The LM2696 is available with an adjustable output in an ex- posed pad TSSOP-16 package. Typical Application Circuit © 2009 National Semiconductor Corporation LM2696 Features ■ Input voltage range of 4.5V–24V ■ ...
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Connection Diagram Pin Descriptions Pin # Name CBOOT 5 AVIN 6 EXTV N/C 9 GND PGOOD 12 RON 13 SD 14, 15, 16 PVIN - Exposed Pad Ordering ...
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... Absolute Maximum Ratings If Military/Aerospace specified devices are required, please contact the National Semiconductor Sales Office/ Distributors for availability and specifications. Voltages from the indicated pins to GND AVIN PVIN CBOOT CBOOT to SW FB, SD, SS, PGOOD Storage Temperature Range Electrical Characteristics apply over the full Operating Temperature Range (T test, design or statistical correlation ...
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Typical Performance Characteristics I vs Temp Shutdown vs Temp Q Shutdown Thresholds vs Temp www.national.com 20153403 I Q 20153405 20153407 20153404 Shutdown IN 20153406 EXTV vs Temp CC ...
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EXTV 20153409 Feedback Threshold Voltage vs Temp 20153411 Switch ON Time vs R Pin Current ON 20153413 EXTV vs Load Current Temp ON Min Off-Time vs Temp 5 20153410 20153412 20153414 www.national.com ...
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Max and Min Duty-Cycle vs Freq (Min T = 400 ns, Min Pin Voltage vs Temp ON www.national.com = 200 ns) OFF 20153415 20153417 6 FET Resistance vs Temp 20153416 Current Limit vs Temp 20153418 ...
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Block Diagram Application Information CONSTANT ON-TIME CONTROL OVERVIEW The LM2696 buck DC-DC regulator is based on the constant on-time control scheme. This topology relies on a fixed switch on-time to regulate the output. The on-time can be set man- ually ...
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CURRENT LIMIT The LM2696 contains an intelligent current limit off-timer. If the peak current in the internal FET exceeds 4.9A the present on-time is terminated; this is a cycle-by-cycle current limit. Following the termination of the on-time, a non-resetable ex- ...
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AC inductor ripple current flows entirely into the output capacitor and the ESR of the capacitor creates the voltage ripple. This is expressed as: ≈ ΔV ΔI • R OUT L ...
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It can be seen that the average output voltage is higher than the gained up reference by exactly half the output voltage rip- ple. The output voltage may then be appended according to the voltage ripple. The appended V pressed ...
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Although EXTV is for internal use, it can be used external rail for extremely light loads (<50 µA). If EXTV is accidentally shorted to GND ...
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UNDER- & OVER-VOLTAGE CONDITIONS The LM2696 has a built in under-voltage comparator that controls PGOOD. Whenever the output voltage drops below the set threshold, the PGOOD open drain FET will turn on pulling the pin to ground. For an over-voltage ...
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Legend Min off-time (165 ns typical On-time (set by the user Min off-time (165 ns typical Blanking time (165 ns typical Extended off-time (12 µs typical) ...
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Several diagrams are shown in Figure 6 illustrating continu- ous conduction mode (CCM), discontinuous conduction mode (DCM), and the boundary condition. It can be seen that in DCM, whenever the inductor runs dry the SW node will become high impedance. ...
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FIGURE 8. Average Output Voltage and Regulation Point The output voltage is given by the following relationship: as discussed in the Feedback Resistor section of this docu- ment. TRANSIENT RESPONSE Constant on-time architectures have inherently excellent tran- sient line and ...
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The components at pins and 13 should be as physically close as possible to the IC, thereby minimizing noise pickup in the PC traces. If the internal dissipation of the LM2696 produces excessive junction temperatures ...
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Bill of Materials (Figure 10: Medium Voltage Board, 5V-to-2.5V conversion, f Designator Function C Input Cap IN C Bypass Cap BY C Soft-Start Cap SS C EXTV EXT CC C Boot BOOT C Analog V AVIN IN C Output Cap ...
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Bill of Materials (Figure 11: Medium Voltage Board, 12V-to-3.3V conversion, f Designator Function C Input Cap IN C Bypass Cap BY C Soft-Start Cap SS C EXTV EXT CC C Boot BOOT C Analog V AVIN IN C Output Cap ...
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Physical Dimensions inches (millimeters) unless otherwise noted eTSSOP-16 Package Order Number LM2696MXA or LM2696MXAX NS Package Number MXA16A 19 www.national.com ...
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