AIC1573 AIC [Analog Intergrations Corporation], AIC1573 Datasheet
AIC1573
Related parts for AIC1573
AIC1573 Summary of contents
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... DAC, Synchronous PWM Power LDO And Linear Controller n DESCRIPTION The AIC1573 combines two PWM voltage mode controllers and two linear controllers as well as the monitoring and protection functions in this chip. One PWM controller regulates the microprocessor core voltage with a synchronous rectified buck converter. ...
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... VSEN2 10 FB1 21 NC SELECT 11 20 VSEN1 VAUX 16 22 DRIVE3 18 VID0 7 VSEN3 19 VID1 6 VID2 5 VID3 4 VID4 3 PGOOD DRIVE4 8 15 FAULT/RT 13 VESN4 GND C5 1nF 10V Q1 680 F OUT1 R1 1000 F*7 10K C6 R2 0.22 F 680K Css AIC1573 +5V IN GND V OUT1 2 ...
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... C/W … … … … … … … ..… … ...... 150 C … … … … … … … … ..… … … .... - 150 C … … … … … … … … … … ..… ... 300 C AIC1573 PIN CONFIGURATION ...
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... TEST CONDITIONS UGATE1, LGATE1, UGATE2, DRIVE3 and DRIVE4 open VOCSET=4.5V VOCSET=4.5V RT=Open 6k <RT to GND<200k RT=open V =1.8V~3.5V DAC Select < 0.8V Select > 2.0V V Rising SEN V Falling SEN V -V > 0.6V AUX DRIVE AIC1573 SYMBOL MIN. TYP. MAX 10.4 CCTHR V 8.2 CCTHF VAUX 2.5 THR VAUX 500 HYS V 1.26 OCSETH F ...
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... UGATE V =12V, V =1V CC LGATE V =1V LGATE V Rising SEN1 - V V =2.0V CC FAULT/RT V =4.5VDC OCSET V Rising SEN1 V Falling SEN1 Upper and Lower Threshold I =-4mA PGOOD AIC1573 SYMBOL MIN. TYP. MAX BWP 0.9 UGH R 2.8 3.5 UGL I 1 LGH R 2.2 3.0 LGL OVP 116 120 I 20 OVP ...
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... SS Fig. 2 Soft Start Initiates PWM Output 10M R Pull Up to 12V T 1M 100k 10k 1k 10k 100k Switching Frequency (Hz) Fig Resistance vs. Frequency T Over Load Applied Fig. 6 Over Current ON Inductor AIC1573 VDAC=3.5V VDAC=2V VDAC=1.3V R Pull Down to GND T 1M Inductor Current 5A/div SS Fault 6 ...
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... Temperature ( C) Fig. 8 Temperature vs. Switching Frequency Drift 0.4 0.3 0.2 0.1 0 -0.2 -0.3 -0.4 -0.5 -0.6 VREG2=3.3V -0.7 -0.8 -40 - Temperature ( C) Fig. 10 Temperature Drift of 9 Different Parts 0.4 0.3 0.2 0.1 0.0 -0.1 -0.2 -0.3 -0.4 -0.5 VREG4=1.8V -0.6 -0.7 -40 - Temperature ( C) Fig. 12 Temperature Drift of 9 Different Parts AIC1573 80 100 120 80 100 120 80 100 120 7 ...
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... Load Transient of PWM Output 70 Mean= -0.006 std.=0.56 -0.6 -0.4 -0.2 0.0 Accuracy (%) Fig Voltage Accuracy V OUT1 Fig. 14 Stringent Load Transient of PWM Output 80 DACOUT=1.6V 70 Ta= 0.2 0.4 0.6 Fig. 16 AIC1573 (Continued 20A Load Step V Mean = 0.16% 3 std.= -1.0 -0.5 0.0 0.5 Accuracy (%) VSEN3 Voltage Accuracy OUT1 1.0 8 ...
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... BLOCK DIAGRAM AIC1573 VSEN1 9 ...
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... Pulling this pin low will shut down the IC. Pin 13: FAULT/RT: Frequency adjustment pin. Connecting a resistor (RT) from this pin to GND, increasing the frequency. Connecting a resistor (RT) from this pin to VCC, de- AIC1573 from this pin internal OCSET ) set the over- DS(ON) R OCSET ...
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... Pin 23: OCSET1: Current limit sense pin. Connect Pin 24: PGND: Pin 25: LGATE1: Lower N-MOSFET gate drive pin PWM converter. Pin 26: PHASE1: AIC1573 nected to FB1 in to compensate the voltage control feedback loop of the converter. The error amplifier inverting i n put pin of the synchronous PWM converter ...
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... Connect UGATE1 to the synchronous PWM con- n APPLICATIONS INFORMATION The AIC1573 is designed for microprocessor com- puter applications with 3.3V and 5V power, and 12V bias input. This IC has two PWM controller and two linear controllers. The first PWM (PWM1) controller is designed to regulate the microproces- ...
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... FAULT/RT pin close to VCC potential. A separate over-voltage circuit provides protection during the initial application of power. For voltage on VCC pin below the power-on reset (and above ~4V), Should VSEN1 exceed 1.0V, the lower MOSFET (Q2) is driven on as needed to regulate VOUT1 to 1.0V. AIC1573 Fault Latch VCC Fault ...
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... Table 1 also shut down the IC. resistor OCSET Oscillator Synchronization The AIC1573 avoids the problem of cross talk b e- tween the converters by way of phase control method. Therefore, for both output voltage settings less than 2.4V or both greater than 2.4V, PWM1 operates out of phase with PWM2. For one PWM output voltage setting below 2 ...
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... AIC1573 UGATE1 @V =1.7V OUT1 @V =1.5V UGATE2 OUT2 PIN NAME VID3 VID2 VID1 VID0 ...
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... Because minimize the transient load magnitude for high slew rate requires low inductance and resistance in circuit board The AIC1573 is best placed over a quiet ground plane area. The GND pin should be connected to the groundside of the output capacitors. Under no ...
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... Inductor value is primarily controlled by the required current respon- se time. The AIC1573 will provide either 0% or 100% duty cycle in response to a load transient. The response time to a transient is different for the application of load and remove of load ...
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... The output capacitor for the linear regulator provides loop stability VEA PWM COMP. Q2 Compensation Networks Fig 20. Control Loop Closed Loop Gain(dB) = Modulation Gain(dB) + Compensation Gain (dB) Modulation Gain(dB) 20 AIC1573 OUT IN OUT V OUT ESR ...
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... But it must be considerably less than that, or there will be large amplitude switching frequency ripple at the output. Thus, the usual practices is to fix F at 1/4 to 1/5 the switching frequency. SYMBOL MIN A 2.35 A1 0.10 B 0.33 C 0.23 D 17.70 E 7.40 e 1.27 (TYP) H 10.00 L 0.40 AIC1573 1M 10M must be less that 0dB MAX 2.65 0.30 0.51 0.32 18.10 7.60 10.65 1.27 19 ...