isl6227 Intersil Corporation, isl6227 Datasheet
isl6227
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isl6227 Summary of contents
Page 1
... DDR memory. The reference voltage VREF required by DDR memory is generated as well. In dual power supply applications the ISL6227 monitors the output voltage of both CH1 and CH2. An independent PGOOD (power good) signal is asserted for each channel after the soft-start sequence has completed, and the output voltage is within PGOOD window ...
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... OCSET1 11 SOFT1 12 DDR 13 VIN 14 Generic Application Circuits V IN +5V TO +28V +5V ISL6227 APPLICATION CIRCUIT FOR TWO CHANNEL POWER SUPPLY V IN +5V TO 28V +5V VREF +1.25V ISL6227 APPLICATION CIRCUIT FOR COMPLETE DDR MEMORY POWER SUPPLY 2 ISL6227 28 VCC 27 LGATE2 26 PGND2 25 PHASE2 24 UGATE2 23 BOOT2 22 ISEN2 21 EN2 20 ...
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... SYMBOL TEST CONDITIONS I LGATEx, UGATEx Open, VSENx forced above CC regulation point, V > CCSN V CCU V CCD I VIN I VINS f Commercial, ISL6227C c Industrial, ISL6227I 16V (Note (Note (Note 5) ROFF ≥ 4.2V (Note RB1 IN ≤ 4.1V (Note RB2 ...
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... OCSET Sourcing Current Range EN - Low (Off High (On) Continuous-Conduction-Mode(CCM) Enforced (HYS Operation Inhibited) Automatic CCM/HYS Operation Enabled DDR - Low (Off) DDR - High (On) DDR REF Output Voltage DDR REF Output Current 4 ISL6227 SYMBOL TEST CONDITIONS V (Note 5) ST 0.0mA < I < 5.0A; 5.0V < V VOUT1 I (Note 5) VSEN ...
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... FREQUENCY MEAN 302 300 298 296 25% QUANTILE 294 292 290 288 286 - TEMPERATURE (°C) FIGURE 5. SWITCHING FREQUENCY OVER-TEMPERATURE 5 ISL6227 100 EFF EFF@ 12V 40 EFF@ 19.5V 30 EFF@ 5V, PWM 20 EFF@ 12V, PWM EFF@ 19.5V, PWM 10 0 1.00 10.0 FIGURE 2. EFFICIENCY OF CHANNEL 2, 1.8V, 1 ...
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... Vo2 FIGURE 9. LOAD TRANSIENT ( CHANNEL 2) (DIODE EMULATION MODE) Vin1 VIN1 Vo1 VO1 VO2 Vo2 FIGURE 11. INPUT STEP-UP TRANSIENT AT PWM MODE 6 ISL6227 (Continued) Vo1 VO1 VPHASE1 Vphase1 ILO1 Ilo1 VO2 Vo2 FIGURE 8. LOAD TRANSIENT ( CHANNEL 1) (FORCED PWM MODE) ...
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... FIGURE 15. SOFT-START INTERVAL AT ZERO INITIAL VOLTAGE OF VO VO1 Vo1 Vphase1 VPHASE1 ILO1 Ilo1 VO2 Vo2 FIGURE 17. OPERATION AT LIGHT LOAD OF 100mA, CHANNEL 1 7 ISL6227 (Continued) VIN1 Vin1 VO1 Vo1 Vo2 VO2 FIGURE 14. INPUT STEP-DOWN TRANSIENT AT HYS MODE EN1 EN1 PG1 PG1 SOFT1 ...
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... Vphase1 ILO1 Ilo1 VO2 Vo2 FIGURE 21. MODE TRANSITION OF HYS EN1 EN1 PG1 PG1 SOFT1 SOFT1 Vo1 VO1 FIGURE 23. SOFT SHUTDOWN INTERVAL 8 ISL6227 (Continued) VO1 Vo1 PG1 PG1 Ilo1 ILO1 Vo2 VO2 FIGURE 20. SHORT-CIRCUIT PROTECTION AT CHANNEL 1 VO1 Vo1 VPHASE2 Vphase2 Ilo2 ILO2 ...
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... FIGURE 27. VIN = 19V, LOAD STEP ON VTT, VDDQ HYS MODE, 0.14A VDDQ VDDQ Vin VIN VTT VTT OCSET2 OCSET2 FIGURE 29. INPUT LINE TRANSIENT IN DDR MODE 9 ISL6227 (Continued) VDDQ VDDQ PGOOD1 PGOOD1 VTT VTT IL1 IL1 FIGURE 26. VIN = 19V, VDDQ 3A STEP LOAD, VTT 3A LOAD VDDQ ...
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... These pins are connected to the resistive dividers that set the desired output voltage. The PGOOD, UVP, and OVP circuits use this signal to report output voltage status. 10 ISL6227 OCSET1 This pin is a buffered 0.9V internal reference voltage. A resistor from this pin to ground sets the overcurrent threshold for the first controller ...
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... PG2/REF pin. It sets the reference voltage of Channel 2 for its regulation. VCC This pin powers the controller. 11 ISL6227 Typical Application Figures 31 and 32 show the application circuits of a dual channel DC/DC converter for a notebook PC. The power supply in Figure 31 provides +2.5V and +1.8V voltages for memory and the graphics interface chipset from a +5 ...
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... VSEN2 VSEN1 PG2_REF PG2_REF VOUT2 VOUT2 PG1 U1 U1 EN1 EN2 EN2 OCSET2_VDDQ/2 SOFT1 OCSET1 SOFT2 SOFT2 Rset1 Csoft2 (N/U) 0.01µF 100k ISL6227 VCC (5V) VCC (5V) Cin2 Cin2 10µF Lo2 Lo2 V V2 (1.8V) 4.7µH Co21 Co21 Co22 220 µF 4.7 µF Cfb2 0.01µF Rfb21 10k Rfb22 ...
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Block Diagram BOOT1 UGATE1 PHASE1 ADAPTIVE DEAD-TIME DIODE EMULATION PGND1 V/I SAMPLE TIMING PWM/HYS TRANSITION LGATE1 VCC MODE CHANGE COMP 1 SAME STATE FOR 8 CLOCK CYCLES REQUIRED TO CHANGE PWM OR HYS MODE HYSTERETIC COMPARATOR 1 ΔV =15mV HYS ...
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... DDR memory chips is also provided. Initialization The ISL6227 initializes if at least one of the enable pins is set high. The Power-On Reset (POR) function continually monitors the bias supply voltage on the VCC pin, and initiates soft-start operation when EN1 or EN2 is high after the input supply voltage exceeds 4 ...
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... ISL6227 R OC FIGURE 34. OUTPUT VOLTAGE PROGRAM Operation Mode Control VOUTx pin programs the two channels of ISL6227 in two different operational modes VOUTx is connected to ground, the channel will be put into a fixed switching frequency of 300kHz CCM, also known as forced PWM mode regardless of load conditions ...
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... The PWM error amplifier is put in clamped voltage during the hysteretic mode. The output voltage through the VOUT pin and the input voltage through the VIN pin are used to 16 ISL6227 determine the error amplifier output voltage and the duty cycle. The error amplifier stays in an armed state while t waiting for the transition to occur ...
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... TABLE 1. PWM COMPARATOR RAMP AMPLITUDE FOR DUAL SWITCHER APPLICATION VIN PIN CONNECTIONS Ch1 and Ch2 Input Voltage Input voltage >4.2V Input voltage <4.2V GND 17 ISL6227 TABLE 2. PWM COMPARATOR RAMP VOLTAGE AMPLITUDE Ch1 Ch2 (EQ. 6) The small signal transfer function from the error amplifier output voltage V Equation 8: ...
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... MOSFETs. Dual-Step Conversion The ISL6227 dual channel controller can be used either in power systems with a single-stage power conversion, when . the battery power is converted into the desired output ...
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... If the overcurrent condition goes away during the 19 ISL6227 first eight clock cycles, normal operation is restored and the overcurrent circuit resets itself at the end of sixteenth clock cycles; see Figure 40. ...
Page 20
... When used in a DDR application with cascaded converters (VTT generated from VDDQ), several methods of synchronization are implemented in the ISL6227. In the DDR mode, when the DDR pin is connected to VCC, the channels operate either with 0° phase shift, when the VIN pin is connected to the GND, or with 90° ...
Page 21
... The formula in the earlier discussion assumes a 75µA sourcing current. Users can tune the sourcing 21 ISL6227 current of the ISEN pin to meet the overcurrent protection and the change the current loop gain. The lower the current sensing resistor, the higher gain of the current loop, which can damp the output LC filter more ...
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... The duty cycle of a buck converter is a function of the input voltage and output voltage. Once an output voltage is fixed, it can be written as Equation 19 --------- The switching frequency ISL6227 is 300kHz. The sw peak-to-peak ripple current going through the inductor can be written as Equation 20 – ---------------------------------------- - ...
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... I driver 23 ISL6227 Q is used because when the MOSFET drain-to-source gd voltage has fallen to zero, it gets charged. Similarly, the turn-off time can be estimated based on the gate charge and the gate drivers sinking current capability. The total power loss of the upper MOSFET is the sum of the switching loss and the conduction loss ...
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... The overvoltage test can be done on ISL6227 by connecting the VSEN pin to an external voltage source or signal generator through a diode. When the external voltage, or signal ...
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... SOFT1 and SOFT2 The soft-start capacitors should be laid out close to this pin. The other side of the soft-start cap should tie to signal ground. 25 ISL6227 PG1 and PG2/REF For dual switcher operations, these two lines are less noise sensitive. For DDR applications, a capacitor should be placed to the PG2/REF pin ...
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... CORNER REF. OPTION 4X BOTTOM VIEW SECTION "C-C" TERMINAL TIP FOR ODD TERMINAL/SIDE FOR EVEN TERMINAL/SIDE 26 ISL6227 L28.5x5 28 LEAD QUAD FLAT NO-LEAD PLASTIC PACKAGE (COMPLIANT TO JEDEC MO-220VHHD-1 ISSUE SYMBOL 0. ...
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... However, no responsibility is assumed by Intersil or its subsidiaries for its use; nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Intersil or its subsidiaries. For information regarding Intersil Corporation and its products, see www.intersil.com 27 ISL6227 ISL6227 M28.15 28 LEAD SHRINK SMALL OUTLINE PLASTIC PACKAGE (0.150” ...