AIC1574 AIC [Analog Intergrations Corporation], AIC1574 Datasheet
AIC1574
Related parts for AIC1574
AIC1574 Summary of contents
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... DS-1574-00 May 22, 01 TEL: 886-3-5772500 with Triple Linear Controllers n DESCRIPTION The AIC1574 combines a synchronous voltage mode controller with three linear controller as well as the monitoring and protection functions in this chip. The PWM controller regulates the microprocessor core voltage with a synchronous rectified buck converter. ...
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... COUT4 10 2.2 F VCC 28 VAUX 23 16 OCSET1 UGATE1 27 DRIVE2 1 PHASE1 26 VSEN2 10 LGATE1 25 PGND 24 SELECT 11 VSEN1 22 DRIVE3 VSEN3 VID0 7 DRIVE4 15 VID1 6 VID2 5 VESN4 14 VID3 4 VID4 3 PGOOD 8 FIX 2 FAULT/ GND COUT1 Q2 D5820 Css AIC1574 +5VIN GND VOUT1 2 ...
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... C/W … … … … … … … ..… … ...... 150 C … … … … … … … … … … … .... - 150 C … … … … … … … … … … ..… ... 300 C AIC1574 PIN CONFIGURATION 28 VCC ...
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... TEST CONDITIONS UGATE, LGATE, GATE3 and VOUT2 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 AIC1574 SYMBOL MIN. TYP. MAX 10.4 CCTHR V 8.2 CCTHF VAUX 2.5 THR VAUX 500 HYS V 1.26 OCSETH F 170 ...
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... UGATE V =12V, V =6V CC LGATE V =1V LGATE V Rising SEN1 - V V =2.0V CC FAULT/RT V =4.5VDC OCSET V Rising SEN1 V Falling SEN Upper and Lower Threshold I =-4mA PGOOD AIC1574 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 R Resistance vs. Frequency T 10M R Pull Up to 12V T 1M 100k 10k 1k 10k 100k Fig. 4 Switching Frequency (Hz) Over Current ON Inductor Over Load Applied Fig. 6 AIC1574 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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... -40 - Fig. 8 Temperature ( C) Temperature Drift of 9 Different Parts 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 - Fig. 10 Temperature ( C) 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 - Fig. 12 Temperature ( C) AIC1574 80 100 120 80 100 120 80 100 120 7 ...
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... Fig. 15 Accuracy (%) V OUT1 DACOUT=1. 0.0 0.2 0.4 0.6 (Continued 20A Load Step Fig. 14 Stringent Load Transient of PWM Output Bandgap Voltage Accuracy 70 Mean=1.266V 60 3 std.= 0. 1.255 1.260 1.265 1.270 Fig. 16 Bandgap Voltage (V) AIC1574 V OUT1 FIX= 1.275 8 ...
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... BLOCK DIAGRAM INHB VSEN1 INHB AIC1574 9 ...
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... SELECT pin. This pin is also monitored for events. Pin 11:SELECT: This pin determines the output voltage of the AGP bus linear regulator. A low TTL input sets the output voltage to 1.5V, while a high input sets the output volt- age to 3.3V. AIC1574 thresholds. The TTL-compatibe under-voltage 10 ...
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... Pin 24:PGND: AIC1574 Signal GND for IC. All voltage lev- els are measured with respect to this pin. the external N-MOS for providing 1.5V power to GTL bus. Connect this pin to the 1.5V linear regulator’s output. This pin is monitored for under- voltage events ...
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... DS(ON) Pin 27: UGATE: Connect UGATE to pin of the ex- n APPLICATION INFORMATIONS The AIC1574 is designed for microprocessor computer applications with 3.3V and 5V power, and 12V bias in- put. This IC has one synchronous PWM controller and three linear controllers. The PWM controller is des- igned to regulate the microprocessor core voltage ...
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... Css recharges and initiates a soft-start cycle again until the counter increments to 3. This sets the fault latch to disable all outputs. Fig. over-current protection until an over load on OUT1. Should excessive current cause VSEN to fall below AIC1574 drive the FAULT/RT pin FAULT LATCH ...
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... VOUT + (inductor ripple Adjusting the Output Voltage of OUTPUT 3 and 4 Shutdown The AIC1574 features a dedicated shetdown pin (SD). A TTL-compatible logic high signal applied to this pin shuts down all four outputs and discharge the soft-start capacitor. The VID codes resulting in an INHIBIT as shown in Table 1 also shut down the IC ...
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... Because minimize the transient load magnitude for high slew rate requires low inductance and resistance in circuit board The AIC1574 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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... ESR, not for capacitance value. A capacitor with suitable ESR will usually have a larger ca- pacitance value than is needed for energy stor- age. A common way to lower ESR and raise ripple AIC1574 PIN NAME DACOUT VID2 VID1 VID0 ...
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... MOSFET, since it turns on into near zero voltage. The upper MOSFET has con- duction loss and switching loss. The gate char- ge losses are proportional to the switching fre- quency and are dissipated by the AIC1574. ; However, the gate charge increases the switch- ing interval, t FET switching losses ...
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... C C OUT3 sient load regulation. PWM Feedback Analysis VEA PWM COMP. Compensation Networks OUT2 IN2 OUT2 and C should be selected for tran- OUT4 V OUT ESR Modulation Gain AIC1574 , OUT2 18 ...
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... KHz ; 30 KHz ; 400 KHz Compensation Gain OdB 20log OSC 0 Modulation Closed Loop LC Gain F ESR F Gain F 100 1k 10k 100k Frequency (KHz) Bode Plot of Converter Gain must be less 0dB at 1/4 to 1/5 the switching 0dB AIC1574 1M 10M 19 ...
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... PHYSICAL DIMENSIONS l 28 LEAD PLASTIC SO (unit: mm SYMBOL AIC1574 MIN MAX 2.35 2.65 0.10 0.30 0.33 0.51 0.23 0.32 17.70 18.10 7.40 7.60 1.27 (TYP) 10.00 10.65 0.40 1.27 20 ...