NX2138CMTR Microsemi Analog Mixed Signal Group, NX2138CMTR Datasheet
NX2138CMTR
Specifications of NX2138CMTR
Related parts for NX2138CMTR
NX2138CMTR Summary of contents
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... PGOOD Device NX2138CMTR Rev. 1.6 12/09/09 n Internal boost schottky diode n Ultrasonic mode operation available n Bus voltage operation from 4.5V to 24V ...
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ABSOLUTE MAXIMUM RATINGS VCC,PVCC to GND & BST to SW voltage ............ -0.3V to 6.5V TON to GND ......................................................... -0.3V to 28V HDRV to SW Voltage .......................................... -0. GND ......................................................... -2V to 30V All other pins ...
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PARAMETER VCC UVLO Under-voltage Lockout V threshold Falling VCC threshold ON and OFF time TON operating current ON -time Minimum off time FB voltage Internal FB voltage Input bias current Line regulation OUTPUT voltage Output range VOUT shut down discharge ...
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PARAMETER ENSW/MODE threshold and bias current PFM/Non Synchronous Mode Ultrasonic Mode Synchronous Mode Shutdown mode Input bias current Current Limit Ocset setting current Over temperature Threshold Hysteresis Under voltage FB threshold Over voltage Over voltage tripp point Internal Schottky Diode ...
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PIN DESCRIPTIONS PIN NUMBER PIN SYMBOL This pin is directly connected to the output of the switching regulator and 1 VOUT senses the VOUT voltage. An internal MOSFET discharges the output during turn off. This pin supplies the internal 5V ...
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BLOCK DIAGRAM VCC(2) Bias TON(16) VIN ON time pulse genearation VOUT VOUT FB(3) OCP_COMP VREF=0.75V start soft start VCC 1M ENSW /MODE(15) MODE 1M SELECTION OVP AGND(6) FBUVLO_latch SS_finished PGOOD(4) Figure 2 - Simplified block diagram of the NX2138 Rev. ...
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TYPICAL APPLICATION (VIN=7V to 22V, VOUT=1.8V/7A) PGOOD Rev. 1.6 12/09/ 1MEG PGOOD 16 TON 100k 9 PVCC 12 HDRV R8 2 BST VCC ...
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Bill of Materials Item Quantity Reference 1 2 CI1 2 1 CO1 3 2 C1,C2, R3,R8 12 ...
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Demoboard waveforms Fig.4 Startup (CH2 1.8V OUTPUT, CH3 PGOOD) Fig.7 Output transient in PFM mode (CH1 SW, CH2 1.8V OUTPUT AC, CH4 OUTPUT CURRENT) Fig. 9 Output ripple at full load (CH1 SW, CH2 1.8V OUTPUT AC, CH4 OUTPUT CURRENT) ...
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Demoboard waveforms(Cont') Fig. 11 Output ripple at no load in synchronous mode (CH1 SW, CH2 1.8V OUTPUT AC, CH4 OUTPUT CURRENT) Fig. 13 Dynamic response in synchronous mode (CH2 1.8V OUTPUT AC, CH4 OUTPUT CURRENT) Fig. 15 Dynamic response in ...
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APPLICATION INFORMATION Symbol Used In Application Information Input voltage Output voltage OUT I - Output current OUT DV - Output voltage ripple RIPPLE F - Working frequency Inductor current ripple RIPPLE Design ...
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For this example, one POSCAP 2R5TPE330MC is chosen as output capacitor, the ESR and inductor current typically determines the output voltage ripple. When VIN reach maximum voltage, the output volt- age ripple is ...
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Based On Stability Requirement ESR of the output capacitor can not be chosen too low which will cause system unstable. The zero caused by output capacitor's ESR must satisfy the re- quirement as below ESR 2 ...
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The divider consists of two ratioed resistors so that the output voltage applied at the Fb pin is 0.75V when the output voltage is at the desired value. The following equation applies to figure 11, which V shows ...
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FB pin voltage is over 90 PGOOD pin is pulled to high after a 1.6ms delay. Smart Over Output Voltage Protection Active loads in some applications can leak cur- rent from a higher voltage than V ...
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PIN MLPQ OUTLINE DIMENSIONS NOTE: ALL DIMENSIONS ARE DISPLAYED IN MILLIMETERS. Rev. 1.6 12/09/09 NX2138 16 ...