ir3508z International Rectifier Corp., ir3508z Datasheet
ir3508z
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ir3508z Summary of contents
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... The XPhase3 expensive, and easier to design while providing higher efficiency than conventional approaches. The IR3508Z disables its current sense amplifiers when entering power savings mode. The recommended use for these Phase ICs is for applications without adaptive voltage positioning where two or more power stages will be operating in power savings mode ...
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... ORDERING INFORMATION Part Number IR3508ZMTRPBF * IR3508ZMPBF * Samples only ABSOLUTE MAXIMUM RATINGS Stresses beyond those listed under “Absolute Maximum Ratings” may cause permanent damage to the device. These are stress ratings only and functional operation of the device, at these or any other conditions, beyond those indicated in the operational sections of the specifications are not implied. ...
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... GATEH falling GATEL rising to 1V Note 1 Compare to V(VCCL) CLKIN = V(VCCL) Measure time from CLKIN<1V to GATEH>1V Compare to V(VCCL) Measure time from CLKIN > (VCCL * 50 PHSOUT > (VCCL *50%). 10pF Load @ o 125 C I(PHSOUT) = -10mA, measure VCCL – PHSOUT I(PHSOUT) = 10mA IR3508Z MIN TYP MAX UNIT 1.0 2.5 1.0 2.5 1.0 2.5 0.4 1.0 2 ...
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... Falling Threshold Voltage Note 1 Hysteresis Note 1 Resistance Floating Voltage Page TEST CONDITION MIN 42 -5 -200 -50 -1 30.0 4.8 -10 -5 2.3 3.6 0.5 0.5 -3 -116 120 -220 520 400 50 200 800 IR3508Z TYP MAX UNIT 52.5 57 mV/ %DC -0.3 5 µ 200 32.5 35.0 V/V 6.8 8.8 MHz 6 V/µs ...
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... Note1 Apply step voltage to V(CSIN+) – V(CSIN-). Measure time to V(GATEL)< 1V. I(BOOST) = 30mA, VCCL = 6.8V Compare to V(VCCL) 8V ≤ V VCC) < 10V ( 10V ≤ V VCC) ≤ 16V ( 4.75V ≤ V BOOST)-V(SW )≤ IR3508Z MIN TYP MAX UNIT -300 -200 -110 mV -200 -100 - 105 130 ...
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... CSIN- Inverting input to the current sense amplifier, and input to synchronous rectification disable comparator. 19 EAIN PWM comparator input from the error amplifier output of Control IC. Body Braking mode is initiated if the voltage on this pin is less than V(DACIN connection. Page IR3508Z Jan 09, 2009 ...
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... PWM LATCH ENABLE + BODY VID6 - BRAKING RAMP COMPARATOR DISCHARGE CLAMP SHARE ADJUST ERROR AMPLIFIER + ISHARE VID6 - VID6 - 3K + DACIN Figure 1: PWM Block Diagram IR3508Z VCC VCCH RESET GATEH DOMINANT CBST VID6 OFF CLK Q VCCL DFFRH GATEL VID6 PGND OFF PSI CURRENT SENSE ...
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... An additional advantage of the architecture is that differences in ground or input voltage, at the phases, have no effect on operation since the PWM ramps are referenced to VDAC. Figure 3 depicts PWM operating waveforms under various conditions. Page Figure 2: Four Phase Oscillator Waveforms IR3508Z Jan 09, 2009 ...
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... MAX MIN T = SLEW − MAX MIN T = SLEW BODYDIODE IR3508Z DUTY CYCLE DECREASE DUE TO LOAD STEADY-STATE DECREASE (BODY BRAKING) OR FAULT OPERATION (VCCLUV, OCP, VID=11111X) BODYDIODE Jan 09, 2009 . The ...
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... The current share amplifier is internally compensated so that the crossover frequency of the current Page Current Sense Amp CSOUT /896 in a multiphase architecture. sw IR3508Z ). If the two time constants match, the L O Jan 09, 2009 ...
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... For proper current sharing the output of current sense amplifier should not exceed (VCCL-1.4V) under all operating condition. IR3508Z THEORY OF OPERATION Block Diagram The Block diagram of the IR3508Z is shown in Figure 5, and specific features are discussed in the following sections. CLKIN PHSIN ...
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... From a system perspective, the PSI input is controlled by the system and is forced low when the load current is lower than a preset limit and forced high when load current is higher than the preset limit. IR3508Z can accept an active low signal on its PSI input and force the drivers into tri-state, effectively, forcing the phase IC into an off state ...
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... Emulated Bootstrap Diode IR3508Z integrates a PFET to emulate the bootstrap diode. If two or more top MOSFETs are to be driven at higher switching frequency, an external bootstrap diode connected from VCCL pin to BOOST pin may be needed. Over Voltage Protection (OVP) The IR3508Z includes over-voltage protection that turns on the low side MOSFET to protect the load in the event of a shorted high-side MOSFET, converter out of regulation, or connection of the converter output to an excessive output voltage. As shown in Figure 7, if IOUT pin voltage is above V(VCCL) – ...
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... DESIGN PROCEDURES - IR3508Z Inductor Current Sensing Capacitor C The DC resistance of the inductor is utilized to sense the inductor current. Usually the resistor R in parallel with the inductor are chosen to match the time constant of the inductor, and therefore the voltage across the capacitor C represents the inductor current. If the two time constants are not the same, the AC component of CS the capacitor voltage is different from that of the real inductor current ...
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... VCC and VCCL pins of the phase IC VCC VCCL To Analog Bus NC NC PHSOUT EAIN CLKIN CSIN - PGND CSIN+ GATEL VCC To LGND Plane To Top MOSFET To Switching Node IR3508Z LGND LGND PLANE PLANE To VIN Ground Ground Polygon Polygon To Inductor Sense Jan 09, 2009 ...
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... IC and to transfer heat to the PCB. • No PCB traces should be routed nor vias placed under any of the 4 corners of the IC package. Doing so can cause the IC to rise up from the PCB resulting in poor solder joints to the IC leads. Page IR3508Z Jan 09, 2009 ...
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... Ensure that the solder resist in-between the lead lands and the pad land is ≥ 0.15mm due to the high aspect ratio of the solder resist strip separating the lead lands from the pad land. • The 4 vias in the land pad should be tented with solder resist 0.4mm diameter, or 0.1mm larger than the diameter of the via. Page IR3508Z Jan 09, 2009 ...
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... The maximum length and width of the land pad stencil aperture should be equal to the solder resist opening minus an annular 0.2mm pull back to decrease the incidence of shorting the center land to the lead lands when the part is pushed into the solder paste. Page IR3508Z Jan 09, 2009 ...
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... Visit us at www.irf.com for sales contact information. Page C/W, θ Data and specifications subject to change without notice. This product has been designed and qualified for the Consumer market. Qualification Standards can be found on IR’s Web site. IR3508Z o C/W TAC Fax: (310) 252-7903 Jan 09, 2009 ...