nx2116 Microsemi Corporation, nx2116 Datasheet
nx2116
Related parts for nx2116
nx2116 Summary of contents
Page 1
... Buck controller IC designed for step down converter applications. They are optimized to convert bus voltages from 2V to 25V to as low as 0.8V output voltage. The NX2116 and 2117 offer an Enable pin that can be used to program the converter's start up voltage using an external divider from bus voltage. These prod- ...
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... V Supply Current (Static Supply Current CC (Dynamic) (Dynamic) Supply Voltage(V ) BST V Supply Current (Static) I BST V Supply Current BST (Dynamic) (Dynamic) Rev. 3.0 03/14/06 NX2116/2116A/2116B/2117/2117A 150 125 C NX2117/2117A 10-LEAD PLASTIC MSOP JA BST 1 HDrv 2 GND 3 4 LDrv 5 VCC SYM Test Condition ...
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... Rev. 3.0 03/14/06 NX2116/2116A/2116B/2117/2117A SYM Test Condition _UVLO V Rising _Hyst V Falling 2116, 2117 S 2116A,2117A 2116B V RAMP Ib Tss NX2116,NX2117 NX2116A, NX2117A NX2116B (Hdrv) I=200mA source (Hdrv) I=200mA sink V -V =4.5V BST =4.5V BST SW Ldrv going Low to Hdrv going H) High, 10%-10% (Ldrv) I=200mA source R (Ldrv) ...
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... An external low cost Transistor can be connected to this pin for external enable control. This pin is the output of error amplifier and is used to compensate the voltage control COMP feedback loop. This pin can also be used to perform a shutdown if pulled lower than 0.3V. Rev. 3.0 03/14/06 NX2116/2116A/2116B/2117/2117A PIN DESCRIPTION 4 ...
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... BLOCK DIAGRAM VCC 1.25V Bias Generator 0.8V EN 1.25/1.15 START 0.8V OSC Digital ramp start Up FB COMP START GND Figure 2 - Simplified block diagram of the NX2116 Rev. 3.0 03/14/06 NX2116/2116A/2116B/2117/2117A FB 0.6V UVLO POR START OC PWM 0.6V CLAMP 1.3V CLAMP Latch Out Hiccup Logic OC BST HDRV SW Control Logic VCC LDRV OC 40uA ...
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... Input voltage Output voltage OUT I - Output current OUT DV - Output voltage ripple RIPPLE F - Working frequency Inductor current ripple RIPPLE Design Example The following is typical application for NX2116A, the schematic is figure 12V IN V =1.8V OUT F =600kHz S I =9A OUT DV <=20mV RIPPLE DV < ...
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... The above equation shows that if the selected out- put inductor is smaller than the critical inductance, the voltage droop or overshoot is only dependent on the ESR Rev. 3.0 03/14/06 NX2116/2116A/2116B/2117/2117A of output capacitor. For low frequency capacitor such as electrolytic capacitor, the product of ESR and ca- pacitance is high and transient spec is dependent on the ESR of capacitor. ...
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... In this case necessary to compen- sate the system with type III compensator. The follow- ing figures and equations show how to realize the type III compensator by transconductance amplifier. Rev. 3.0 03/14/06 NX2116/2116A/2116B/2117/2117A ...
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... ESR C OUT 440uF 60.3kHz 2. Set R equal to 20k . 20k 0.8V 2 REF 1.8V-0.8V OUT REF Rev. 3.0 03/14/06 NX2116/2116A/2116B/2117/2117A Choose R 3. Set zero F 4. Calculate R frequency at 1/10~ 1/5 of the switching frequency. Set F =50kHz =916pF 1.5V = 12V =17.2k Choose C 5. Calculate C F double pole by equation (11). ...
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... ESR OUT OUT 1 2 1uH 3000uF 2.9kHz 1 F ESR 2 ESR C OUT 1 2 6.5m 3000uF 8.2kHz Rev. 3.0 03/14/06 NX2116/2116A/2116B/2117/2117A 2. Set OUT Choose R 3. Set zero F 4. Calculate =3.5nF Choose C 5. Calculate 5. Choose R 6. Calculate R ...
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... ESR Figure 6 - Bode plot of Type II compensator Rev. 3.0 03/14/06 NX2116/2116A/2116B/2117/2117A Vout R2 and Figure 7 - Type II compensator with For this type of compensator, F ... (17) F <F <<F LC ESR The following is parameters for type II compensa- tor design. Input voltage is 12V, output voltage is 1.8V, ...
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... where R is part of the compensator, and the value value can be set by voltage divider. 1 See compensator design for R Rev. 3.0 03/14/06 NX2116/2116A/2116B/2117/2117A Vout R2 V OUT V REF R1 1 2.0mA/V Figure 8 - Voltage divider Input Capacitor Selection Z Input capacitors are usually a mix of high frequency ceramic capacitors and bulk capacitors ...
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... Figure 9 - Enable and Shut down the NX2116 with Enable pin. The start up of NX2116 can be programmed through resistor divider at Enable pin. For example, if the input bus voltage is12V and we want NX2116 starts when Vbus . ..(21) is above 9V. We can select using the following equa- ...
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... The goal is to localize the high current path to a separate loop that does not interfere with the more sen- sitive analog control function. These two grounds must be connected together on the PC board layout at a single point. Rev. 3.0 03/14/06 NX2116/2116A/2116B/2117/2117A vbus SW OCP 3.656k 14 ...