APU3146 Advanced Power Electronics Corp., APU3146 Datasheet
APU3146
Specifications of APU3146
Related parts for APU3146
APU3146 Summary of contents
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... Comp2 PGood PGood SS1 / SD C10 SS2 / SD Figure 1 - Typical application of APU3146 in 2-phase configuration with inductor current sensing PACKAGE ORDER INFORMATION Data and specifications subject to change without notice. Technology Licensed from International Rectifier DESCRIPTION The APU3146 IC combines a Dual synchronous Buck controller, providing a cost-effective, high performance and flexible solution ...
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... APU3146 ABSOLUTE MAXIMUM RATINGS Vcc, V Supply Voltage .............................................. -0.5V To 16V CL VcH1 and VcH2 Supply Voltage ................................ PGOOD................. ................................................... Storage Temperature Range ...................................... -40°C To 125°C Operating Junction Temperature Range ..................... -40°C To 125°C Caution: Stresses above those listed in Absolute Maximum Ratings" may cause permanent damage to the device. ...
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... OCSet Hiccup pin pulled high, Note1 Note1 T C =1500pF, Figure =1500pF, Figure Figure Fb=0.6V, F =300KHz MAX SW D Fb=1V MIN F =300KHz, Note1 SW Note 1 APU3146 MIN TYP MAX UNITS 0.8 0.9 0. REF REF REF 0.8 0.9 0. REF REF REF 0.1 0.5 -0 ...
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... APU3146 DEADBAND TIME Tr 90% High Side 2V Driver HD 10% 90% Low Side 2V Driver LD 10% Deadband H_to_L PIN DESCRIPTIONS PIN# PIN SYMBOL PIN DESCRIPTION 1 PGood Power Good pin. Low when any of the outputs fall 10% below the set voltages. 2 Vcc Supply voltage for the internal blocks of the IC. ...
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... Set1 Ramp1 S Reset Dom Two Phase Oscillator Set2 Ramp2 Reset Dom S SS1 PWM Comp2 Q SS2 R Mode 0.3V SS2 OVP PGood / OVP HDrv OFF / LDrv ON Regulator Figure 3 - Block diagram of APU3146. APU3146 V POR P2 Mode VcH1 18 Control 0.8V Mode HDrv1 LDrv1 15 SS1 PGnd1 16 3uA ...
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... Independent Mode In this mode the APU3146 provides control to two inde- pendent output power supplies with either common or different input voltages. The output voltage of each indi- vidual channel is set and controlled by the output of the error amplifier, which is the amplified error signal from the sensed output voltage and the reference voltage ...
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... Dual Soft-Start The APU3146 has programmable soft-start to control the output voltage rise and limit the inrush current during start-up. It provides a separate Soft-Start function for each outputs. This will enable to sequence the outputs by controlling the rise time of each output through selection of different value soft-start capacitors. The soft-start pins will be connected together for applications where, both outputs are required to ramp-up at the same time ...
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... Figure 8 - 3uA current source for discharging soft start-capacitor during Hiccup mode Out-of-Phase Operation The APU3146 drives its two output stages 180 out-of- phase. In 2-phase configuration, the two inductor ripple currents cancel each other and result in a reduction of the output current ripple and yield a smaller output ca- pacitor for the same ripple voltage requirement ...
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... FET drivers turn-on, thus crowbaring the out- puts. Reset is performed by recycling either Vcc. Error Amplifier The APU3146 is a voltage mode controller. The error am- plifiers are of transconductance type. In independent mode, each amplifier closes the loop around its own output volt- age ...
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... OUT 0.8V P2 REF When an external resistor divider is connected to the output as shown in Figure 11. APU3146 V Fb REF V P Figure 11 - Typical application of the APU3146 for programming the output voltage. Equation (4) can be rewritten as OUT × Will result to ...
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... The capacitors value must be high enough to absorb the V IN inductor's ripple current. ---(7) Power MOSFET Selection The APU3146 uses four N-Channel MOSFETs. The se- lections criteria to meet power transfer requirements is based on maximum drain-source voltage (V source drive voltage (V resistance R DS(ON) The both control and synchronous MOSFETs must have ...
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... APU3146 The gate drive requirement is almost the same for both MOSFETs. Logic-level transistor can be used and cau- tion should be taken with devices at very low V vent undesired turn-on of the complementary MOSFET, which results a in shoot-through. The total power dissipation for MOSFETs includes con- duction and switching losses ...
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... Feedback Compensation The APU3146 is a voltage mode controller; the control loop is a single voltage feedback path including error amplifier and error comparator. To achieve fast transient response and accurate output regulation, a compensa- tion circuit is necessary. The goal of the compensation network is to provide a closed loop transfer function with the highest 0dB crossing frequency and adequate phase margin (greater than 45 ) ...
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... APU3146 F × ESR OSC × O1 × × Where Maximum Input Voltage Oscillator Ramp Voltage OSC F = Crossover Frequency Zero Frequency of the Output Capacitor ESR F = Resonant Frequency of the Output Filter LC R and R = Resistor Dividers for Output Voltage ...
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... RC circuit as shown in Figure 17: Ve(s) D( × Typical Output Capacitor Figure 17 - The PI compensation network /2 Electrolytic, Tantalum /2 Tantalum, The loop gain function is: Ceramic Ceramic ZO H(s)=[G(s) × D(s) × H(s)=R × S2 APU3146 OUT = ---(18) sL × OSC ( ) ( ) × × m ...
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... APU3146 Select a zero crossover frequency for control loop (F 1.25 times larger than zero crossover frequency for volt- age loop ( ≅ 1.25% H(Fo) = ×R ×R × 2π×Fo×L From (20), R can be express as × 2π × F × ...
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... C3 C4 1uF 1uF C5 1uF R2 33K R3 C8 20nF 2. 18nF 2.61K PGood C10 0.1uF C15 0.1uF Figure 19 - Typical application of APU3146. 12V input and two independent outputs. C12 1uF C13 V VcH1 VcH2 V 1uF CL OUT3 HDrv1 Vcc R1 OCSet1 7.8K LDrv1 Hiccup PGnd1 V P2 ...
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... APU3146 TYPICAL OPERATING CHARACTERISTICS Test Conditions: V =12V, V =2.5V, I =0-10A OUT1 OUT1 Figure 20 - Input Supply Ramps up. Ch1: 1.8V, Ch2: 2.5V, Ch3: Input Supply Figure 22 - Normal condition at No Load. Ch1: HDrv2, Ch2: HDrv1, Ch3 and Ch4: Inductor Currents Ch3:ch4: 5A/div =1.8V, I =0-10A, Fs=300KHz OUT2 OUT2 Figure 21 - Input Supply Ramps up/down ...
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... Ch1: SS2, Ch2: 1.8V, Ch3: SS1, Ch4: 2.5V Figure 26 - Deadband Time (1.8V Output). Ch1: LDrv2, Ch2: HDrv2, Ch3: Switching Node =1.8V, I =0-10A, Fs=300KHz OUT2 OUT2 Ch1: Vin, Ch2: Vout3(LDO), Ch3: SS2, Ch4: SS2 Figure 27 - Deadband Time (2.5V Output). Ch1: LDrv1, Ch2: HDrv1, Ch3: Switching Node APU3146 Figure 25 - Soft_Start. 19/28 ...
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... APU3146 TYPICAL OPERATING CHARACTERISTICS Test Conditions: V =12V, V =2.5V, I =0-10A OUT1 OUT1 Figure 28 - Shut Down (Pulling down the SS1 pin). Ch1: HDrv1, Ch2: LDrv1, Ch3: SS1 Figure 30 - High side and Low side Drivers peak Current for 1.8V Output Ch1: HDrv2, Ch2: LDrv2, Ch3: High Side Peak ...
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... Ch1: Input Supply, Ch2: 2.5V Output, Ch3: 1.8V Output, Ch4 : Power Good Signal =1.8V, I =0-10A, Fs=300KHz OUT2 OUT2 Figure 33 - Load Transient Response. Ch1: 1.8V, Ch3: Step Load (0-10A) Figure 35 - Short Circuit Condition (Hiccup Mode). Ch1: SS1 pin, Ch2: SS2 pin, Ch3 and Ch4 : Inductor APU3146 Ch3:ch4: 5A/div Currents Ch3:ch4: 10A/div 21/28 ...
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... Figure 36 - 2-phase operation with inductor current sensing. C14 C13 3x 47uF VcH1 VcH2 V 1uF OUT3 Q2 HDrv1 IRFR3706 R1 OCSet1 12K Q3 LDrv1 IRFR3711 PGnd1 BAT54A U1 APU3146 V SEN1 V SEN V SEN2 Fb1 Fb2 C17 3x 47uF Q4 HDrv2 R6 IRFR3706 OCSet2 12K Q5 LDrv2 IRFR3711 PGnd2 Gnd 12V to 1.8V @ 30A output D1 ...
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... BAT54A U1 APU3146 V SEN1 V SEN V SEN2 Fb1 Fb2 C17 3x 47uF Q4 HDrv2 IRFR3706 R6 OCSet2 12K Q5 LDrv2 IRFR3711 PGnd2 Gnd 12V to 1.8V @ 30A output APU3146 D1 BAT54S C11 0.1uF L3 R5 1.8V @ 30A 1uH 2m Ω C16 8x 330uF, 40m Ω 6TPB330M R20 1.24K V SEN R21 1K R7 1.24K 1uH 2m Ω ...
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... R3 C8 Comp1 22nF 2.2K C6 120pF R4 C9 Comp2 4.7nF 23K C7 27pF PGood PGood SS1 / SD C10 SS2 / SD 0.1uF Figure 38 - Typical application of APU3146 using 5V and 12V supplies to generate single output voltage. C12 C13 1uF 1uF C14 3x 47uF VcH1 VcH2 V OUT3 Q2 HDrv1 IRFR3706 R1 OCSet1 12K Q3 LDrv1 ...
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... BAT54A U1 V SEN1 V SEN2 Fb1 Fb2 Q4 HDrv2 IRFR3706 R6 OCSet2 10K Q5 LDrv2 IRFR3711 PGnd2 Gnd Figure 39 - Typical application of APU3146. ( and 12V @ 3A) APU3146 C11 0.1uF L3 R5 1.8V @ 30A 1uH 2m Ω C16 8x 330uF, 40m Ω 6TPB330M R20 1.24K R21 1K R7 1.24K 1uH 3m Ω ...
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... Figure 40 - Single 5V input and two independent outputs. C12 1uF C13 V VcH1 V VcH2 1uF CL OUT3 HDrv1 Vcc R1 OCSet1 10K LDrv1 Hiccup PGnd1 V P2 Sync V REF U1 Rt APU3146 V SEN1 V Comp1 SEN2 Fb1 Fb2 Comp2 HDrv2 R6 OCSet2 8.5K PGood LDrv2 SS1 / SD PGnd2 SS2 / SD Gnd D1 BAT54S C11 0.1uF C14 3x 330uF 6TPB330M ...
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... V REF U1 Rt APU3146 V SEN1 V Comp1 SEN2 Fb1 Fb2 Comp2 HDrv2 R6 OCSet2 5.1K PGood LDrv2 SS1 / SD PGnd2 Gnd SS2 / SD Figure 41 - Typical application of APU3146. APU3146 C14 3x 330uF 6TPB330M Q2 L3 IRF7457 1.8V @ 10A 1uH Q3 C16 IRF7460 4x 330uF, 40m Ω R20 6TPB330M 1.24K V SEN1 D2 BAT54A R21 ...
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... V REF U1 V SEN1 Rt V SEN2 APU3146 Fb1 Comp1 Fb2 Comp2 HDrv2 R6 OCSet2 8.5K PGood LDrv2 SS1 / SD PGnd2 SS2 / SD Gnd Figure 42 - Typical application of APU3146. D1 BAT54S C11 0.1uF C14 2x 330uF 6TPB330M Q2 L3 1/2 IRF7910 2. 3.3uH Q3 C16 1/2 IRF7910 2x 330uF, 40m Ω R20 6TPB330M 2.14K V SEN1 D2 BAT54A ...