AIC1531CSTB

AIC1531 500mA Dual Linear Regulator with Internal Power Switch n FEATURES l l l l l n DESCRIPTION AIC1531 is a dual input regulator with VAUX switch capable of delivering 3.3V/500mA continuously. The output power is provided from three independent input voltage sources on a prioritized basis. Power is always taken in priority using the following order VCC, VSBY, and VAUX . The AIC1531 meets Intel’s “ Instantly Available ” power requirements which follows the “Advanced Configuration and Power Interface“ (ACPI) Continuous 3.3V Output from Three Inputs. Complete Power Management Solution. VCC, VSBY Regulator Supplies 500mA Output. Built-in Hysteresis When Selecting Input Supplies. Integrated Switch has Very Low RDS(ON) 120mΩ (typ.). Integrated Switch Supplies 500mA From VAUX . Output can be Forced Higher than Input (Off-State). l l n APPLICATIONS l l l l l Desktop Computers. PCI Adapter Cards with Wake-On-LAN. Network Interface Cards (NICs). Multi Power System. System with Standby Capabilities. standards. When either V CC or V SBY is present, the device automatically enables the regulator and produces a stable 3.3V output VOUT . When only VAUX (3.3V) is present, the device provides a low impedance direct connection (120mΩ typ.) from VAUX to VOUT . The AIC1531 also prevents excessive current from flowing V OUT to either input voltage or ground when the output voltage is higher than the input voltage. All the necessary control circuitry needed to provide a smooth and automatic transition between all the three supplies has been incorporated. This allows both V CC and V SBY to be dynamically switched without loss of output voltage. Analog Integrations Corporation 4F, 9 Industry E. 9th Rd, Science-Based Industrial Park, Hsinchu, Taiwan TEL: 886-3-5772500 FAX: 886-3-5772510 www.analog.com.tw DS-1531-00 022502 1 AIC1531 n TYPICAL APPLICATION CIRCUIT 1 VSBY_5V + C1 10µ F VCC_5V + C2 10µF VAUX_3.3V AIC1531 3 4 VOUT AUX 2 VSBY VCC 8 GND 7 GND 6 GND 5 GND + C3 10µ F 3.3V/500mA Dual Input Regulator with Auxiliary Power Switch n ORDERING INFORMATION AIC1531CXXX PACKING TYPE TR: TAPE & REEL TB: TUBE PACKAGE TYPE N: PLASTIC DIP S: SMALL OUTLINE PIN CONFIGURATION DIP-8 SO-8 TOP VIEW VSBY 1 VCC 2 VOUT 3 AUX 4 8 GND 7 GND 6 GND 5 GND Example: AIC1531CSTR à in SO-8 Package & Taping & Reel Packing Type (CN is not available in Tape & Reel packing type.) n ABSOLUTE MAXIMUM RATINGS VCC, VSBY Input Voltage ..................................................................................................7.0V VAUX Input Voltage ...........................................................................................................4.0V VOUT Output Voltage ........................................................................................................5.0V Operating Temperature Range ............................................................................... -40°C~85°C Storage Temperature Range...............................................................................-65°C ~ 150°C 2 AIC1531 n ELECTRICAL CHARACTERISTICS (VIN= 5V, TA=25° C, unless otherwise specified.) PARAMETERS Regulated Output Voltage Regulated Output Current VCC selected Output Voltage Load Regulation ILOAD=50mA ~ 500 mA VSBY selected ILOAD=50mA ~ 500mA Output Voltage Line Regulation VCC Select Voltage VCC Deselect Voltage VSBY Select Voltage VSBY Deselect Voltage Hysteresis Voltage Auxiliary Switch Resistance Short Circuit Current VCC Pin Reverse Leakage VSBY Pin Reverse Leakage AUX Pin Reverse Leakage VCC Supply Current (when VSBY is not present) VSBY Supply Current (when VCC is not present) VAUX Supply Current VCC , VSBY are deselected VCC/SBY=5V, VOUT =0V One supply input taken to ground while the others remain at nominal voltage VCC > VCCSEL , ILOAD=0mA VCCDES > VCC > VOUT VOUT > VCC VSBY > VCCSEL , ILOAD=0mA VSBYDES > VSBY > VOUT VOUT > VSBY VCC or VSBY > VOUT VCC and VSBY < VOUT Both VCC and VSBY are deselected Ground Current VCC/SBY=5V , ILOAD = 0mA VCC/SBY=5V , ILOAD = 500mA 70 50 10 70 50 10 10 50 60 100 100 300 200 20 300 200 20 100 400 300 500 500 µA µA µA µA 5 50 µA VCC=4.5V~5.5V, ILOAD=5mA VSBY=4.5V~5.5V, ILOAD=5mA VSBY > VSBYDES or VAUX present VCC < VCCDES VAUX present VSBY< VSBYDES 3.90 3.90 2 4.50 4.20 4.50 4.20 0.30 120 1000 200 4.60 4.60 mV 20 mV CONDITIONS 0mA < ILOAD < 500mA MIN. 3.135 500 TYP. 3.300 MAX. 3.465 UNIT V mA V V V mΩ mA 3 AIC1531 n TYPICAL PERFORMANCE CHARACTERISTICS VCC VC C VOUT VOUT 500mA 500mA Fig. 1 VCC Cold Start Fig. 2 VC C Full Power Down VSBY VSBY VOUT 500mA 500mA VOUT Fig 3. VSBY Cold Start Fig. 4 VSBY Full Power Down. VAUX VAUX VOUT 500mA VOUT 500mA Fig. 5 VAUX Cold Start Fig. 6 VAUX Full Power Down. 4 AIC1531 n TYPICAL PERFORMANCE CHARACTERISTICS (Continued) V SBY VSBY VCC VCC VOUT 375mA 375mA VOUT Fig. 7 VCC Power Up ( VSBY =5V) Fig. 8 VCC Power down ( VSBY =5V) VCC VCC VOUT 375mA VOUT 375mA Fig. 9 V Power Up ( VAUX = 3.3V) CC Fig. 10 VCC Power Down ( VAUX = 3.3V) IOUT 5mA→ 500mA IOUT 500mA→5mA VOUT VOUT Fig. 11 VCC Load Transient Rising Fig. 12 VCC Load Transient Falling 5 AIC1531 n TYPICAL PERFORMANCE CHARACTERISTICS (Continued) VCC 4.5V→5.5V VCC 5.5V→4.5V VOUT 5mA Loading VOUT 5mA Loading Fig. 13 3.40 3.35 3.30 3.25 3.20 3.15 3.10 3.05 3.0 VCC Line Transient Rising 3.400 Fig. 14 V C Line Transient Falling C 100mA 500mA 3.375 3.350 VOUT (V) V OUT ( V) 3.325 3.300 3.275 3.250 3.225 3.200 0 200 400 600 800 3.5 4.0 4.5 5.0 VCC (V) Load Current (mA) Fig. 11 180 V CC Line Regulation 3.280 Fig. 16 Load Regulation 160 3.275 Resistance (mΩ) 140 3.270 V OUT (V) 120 3.265 100 3.260 80 3.255 60 2.7 3.0 3.3 3.6 3.250 -40 -20 0 20 40 60 80 100 V current LoadAUX (V) Fig. 17 VAUX Switch Resistance vs. VAUX Temperature (°C) Fig. 18 Output Voltage vs. Temperature 6 AIC1531 n BLOCK DIAGRAM n PIN DESCRIPTION PIN 1: VSBY - Standby supply voltage (5V) input for 3.3V regulator when VCC falls below VCCDES. Some NICs that operate in “ Wake-On-LAN” mode get a 5V standby through a cable that connects directly to a specific header on the Motherboard. PIN 2: VCC - Primary supply voltage (5V) input for 3.3V regulator. When only VAUX (3.3V) is present, VOUT voltage comes from VAUX through an internal low impedance switch. PIN 4: AUX PIN 5-8: GND - Auxiliary supply voltage (3.3V) input for low impedance switch. - Negative reference for all voltages. PIN 3: VOUT - 3.3V regulated output voltage when either VCC or V SBY is present. n APPLICATIONS INFORMATION The Requirement for External Capacitors The selection of the output capacitor is based on two requirements: LDO compensation and the transition between power sources. During the takeover between sources, the output capacitor provides the loading. Therefore a larger output capacitor can improve the transition. And since the output capacitor plays the important role in the compensation of LDO, a 10µF Tantalum capacitor or larger is recommended. The input capacitor is required to be as close to the The layout and Thermal Considerations The AIC1531 is housed in a thermally enhanced package where the GND pins (Pin5 to Pin8) are integrated to the leadframe. Generally, heat sinks are not available for most surface-mounted devices. IC as possible. The input capacitor can reduce the parasitic effect formed by the power supply output impedance or the trace. A 10µF Tantalum capacitor is a good choice. Additional ceramic capacitor can be placed close to input and output to reduce the high frequency noise. A 0.1µF is recommended. 7 AIC1531 Instead, they rely on the printed-circuit board to provide the thermal path. When the AIC1531 operates normally, the maximum power dissipation is PD = (VIN − VOUT ) × IOUT = (5 − 3.3) × 0.5 = 0.85W used thermal path. To make sure the thermal resistance small enough and the shutdown function work normally, the thermal resistance between GND pins to GND plane should be as small as possible by means of adding more vias. And the GND plane should be at least 1 square centimeters of copper. The layout of AIC1531 is shown in Fig.1. In Fig. 2, the thermal resistance RJA is 70.36°C/W where the AIC1531 is mounted on the double-sided PCB and measured under the forced-air thermal chamber. At the maximum operation temperature, the thermal resistance seen by the device, or the combination of all the thermal paths, should be 165 − 85 R JA < = 94 °C/W . 0.85 When the device is mounted on a double-sided printed circuit board, the ground plane is the most Fig.19 The layout of AIC1531 2.6 2.4 Power Dissipation (W) 2.2 2.0 1.8 1.6 1.4 1.2 1.0 0.8 0 20 40 60 80 100 Ambient Temperature (°C) Fig.20 The power thermal shutdown dissipation vs. ambient temperature where RJA is 70.36°C/W in the forced-air thermal chamber 8 AIC1531 The Application circuits USB_5V Q1 si2301 R7 51k C1 10µF + VOUT _3.3V U2 1 2 3 4 VSBY VCC VOUT AUX GND GND GND GND 8 7 + 22µ H L1 VIN + R1 22 C4 22µF C9 1µF 27K R3 U1 1 2 3 4 D1 SS12 8 VOUT 7 VIN SW SGND LBI 6 LBO 5 CGND AIC1631 ILIM/SD C11 + 220µF R5 15k R6 12k R8 30K + 6 5 C5 47 µF C13 10µ F AIC1531 Fig.21 The Step Up/Down converter with OR function for dual power system 22µH L1 VIN + D1 SS12 U1 USB_5V + C4 10 µF U2 1 8 2 3 + R1 22 C1 22 µ 27K R2 VOUT_3.3V GND 8 GND 7 GND 6 GND 5 + C2 1µ 1 ILIM/SD VOUT 7 2 VIN LBI 6 3 SW LBO 5 4 SGND CGND AIC1631 VSBY VCC VOUT AUX C3 220µF 4 C5 47 µF AIC1531 Fig.22 The Step Up converter with OR function for dual power system USB_5V + C4 10µ F U2 V OUT_3.3V V IN 2.7~5.5V U1 1 VOUT C1 10µ F 2 GND CAP 6 C3 10µ F C2 1µ F 1 2 3 4 VIN 5 CAP 4 VSBY VCC VOUT AUX GND GND GND GND 8 7 + 6 5 C5 22µ F 3 SHDN AIC1531 AIC1845 Fig. 23 The Step Up/Down converter with OR function for dual power system 9 AIC1531 n PHYSICAL DIMENSIONS l 8 LEAD PLASTIC SO (unit: mm) D SYMBOL A H E MIN 1.35 0.10 0.33 0.19 4.80 3.80 MAX 1.75 0.25 0.51 0.25 5.00 4.00 1.27(TYP) A1 B C e A C A1 D E e H L 5.80 0.40 6.20 1.27 B L l 8 LEAD PLASTIC DIP (unit: mm) D SYMBOL A1 E1 MIN 0.381 2.92 0.35 0.20 9.01 7.62 6.09 MAX — 4.96 0.56 0.36 10.16 8.26 7.12 A2 b E C D E C A2 A1 L E1 eB b e e eB L — 2.54 (TYP) 10.92 3.81 2.92 10