ACT412 Rev 1, 30-Oct-13 ActivePSRTM Quasi-Resonant PWM Controller FEATURES mode including cycle-by-cycle current limiting. • Patented Primary Side Regulation ACT412 is to achieve no overshoot and very short rise time even with big capacitive load (10000µF) with the built-in fast and soft start process, . Technology • Quasi-Resonant Operation The Quasi-Resonant (QR) operation mode can effectively improve efficiency, reduce the EMI noise and further reduce the components in input filter. • Adjustable up to 120kHz Switching Frequency • +/-5% Output Voltage Regulation • Constant Power Operation Mode for Fast ACT412 is idea for application up to 36 Watt. Figure 1: Start-up and Motor Drive Applications Simplified Application Circuit • Integrated Line and Primary Inductance Compensation • Built-in Soft-Start Circuit • Line Under-Voltage, Thermal, Output Overvoltage, Output Short Protections • • • • Current Sense Resistor Short Protection Transformer Short Winding Protection Less than 100mW Standby Power Complies with Global Energy Efficiency and CEC Average Efficiency Standards • Tiny SOT23-6 Packages APPLICATIONS • AC/DC Adaptors/Chargers for E-Shaver, Motor Driver, ADSL, Network Power, Cell Phone • Big Capacitive Load Application GENERAL DESCRIPTION The ACT412 is a high performance peak current mode PWM controller which applies ActivePSRTM and ActiveQRTM technology. ACT412 achieves accurate voltage regulation without the need of an opto-coupler or reference device. The ACT412 is designed to achieve less than 100mW Standby Power. By applying frequency fold back and ActiveQRTM technology, ACT412 exceeds the latest ES2.0 efficiency standard. ACT412 integrates comprehensive protection. In case of over temperature, over voltage, short winding, short current sense resistor, open loop and overload conditions, it would enter auto restart Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. -1- www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 ORDERING INFORMATION PART NUMBER TEMPERATURE RANGE PACKAGE PINS PACKING METHOD ACT412US-T -40°C to 85°C SOT23-6 6 TUBE & REEL TOP MARK FRYS PIN CONFIGURATION SOT23-6 ACT412US PIN DESCRIPTIONS PIN NAME DESCRIPTION 1 CS 2 GND Ground. 3 GATE Gate Drive. Gate driver for the external MOSFET transistor. 4 VDD 5 FB 6 COMP Current Sense Pin. Connect an external resistor (RCS) between this pin and ground to set peak current limit for the primary switch. Power Supply. This pin provides bias power for the IC during startup and steady state operation. Feedback Pin. Connect this pin to a resistor divider network from the auxiliary winding. Compensation Pin. Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. -2- www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 ABSOLUTE MAXIMUM RATINGSc PARAMETER VALUE UNIT FB, CS, COMP to GND -0.3 to + 6 V VDD, GATE to GND -0.3 to + 22 V 0.45 W -40 to 150 ˚C 220 ˚C/W Operating Junction Temperature -40 to 150 ˚C Storage Temperature -55 to 150 ˚C 300 ˚C Maximum Power Dissipation (SOT23-6) Operating Junction Temperature Junction to Ambient Thermal Resistance (θJA) Lead Temperature (Soldering, 10 sec) c: Do not exceed these limits to prevent damage to the device. Exposure to absolute maximum rating conditions for long periods. ELECTRICAL CHARACTERISTICS (VDD = 18V, LM = 0.5mH, RCS = 0.75Ω, VOUT = 13V, NP = 68, NS =12, NA = 17, TA = 25°C, unless otherwise specified,12V0.4A application) PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT 11.11 12.35 13.58 V 4.8 5.4 6 V 18.45 20.5 22.55 V 5 10 µA 1 mA Supply VDD Turn-On Voltage VDDON VDD Rising from 0V VDD Turn-Off Voltage VDDOFF VDD Falling after Turn-on VDD Over Voltage Protection VDDOVP VDD Rising from 0V Start Up Supply Current IDDST VDD = 11V, before VDD Turn-on IDD Supply Current IDD VDD = 12V, after VDD Turn-on (no switching) 0.55 IDD Supply Current at Fault Mode IDD VDD = 12V, after VDD Turn-on, fault = 1 0.25 mA Feedback Effective FB Reference Voltage VFBREF FB Sampling Blanking Time TFB_BLK Time needed for FB Sampling (After blanking) FB Leakage Current TFB_SAMP IBVFB 2.23 2.25 2.28 V Light load 0.38 0.45 0.52 µs Heavy Load 1.1 1.3 1.5 µs FB sampling 0.5 0.65 0.75 µs CC and Knee point detecting 0.22 0.25 0.29 µs 1 µA VFB = 3V Current Limit CS Current Limit Threshold CS Minimum Current Limits Threshold VCSLIM1 VOUT = 12V 0.5 V VCSLIM2 VOUT = 6V 0.75 V 300 mV 60 ns Light Load 150 ns Heavy Load 636 ns VCSMIN CS to GATE Propagation Delay Leading Edge Blanking Time Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. TCSBLANK -3- www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 ELECTRICAL CHARACTERISTICS CONT’D (VDD = 18V, LM = 0.5mH, RCS = 0.75Ω, VOUT = 13V, NP = 68, NS =12, NA = 17, TA = 25°C, unless otherwise specified,12V0.4A application) PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT 250 ns GATE DRIVE Gate Rise Time TRISE VDD = 10V, CL = 1nF 150 Gate Falling Time TFALL VDD = 10V, CL = 1nF 90 ns Gate Low Level ON-Resistance RONLO ISINK = 30mA 10 Ω Gate High Level ON-Resistance RONHI ISOURCE = 30mA 31 Ω GATE = 18V, before VDD turn-on Gate Leakage Current 1 µA COMPENSATION Inside Compensate Resistor RCOMP Output Sink Current ICOMP_SINK Output Source Current ICOMP_SOUR ACT412 0 kΩ VFB = 3V, VCOMP = 2V 15 40 µA VFB = 1.5V, VCOMP = 2V 15 40 µA 71 µA/V CE Transconductance of Error Amplifier Gm Maximum Output Voltage VCOMPMAX VFB = 1.5V 3.5 V Minimum Output Voltage VCOMPMIN VFB = 3V 0.4 V CS to COMP Gain 2 V/V Pre-Amp Gain 1 V/V COMP Leakage Current COMP = 2.5V 1 µA 132 kHz OSCILLATOR Maximum Switching fMAX 108 120 Maximum Duty Cycle DMAX 65 75 % 1164 Hz Minimum Switching Frequency Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. fMIN -4- www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 ELECTRICAL CHARACTERISTICS CONT’D (VDD = 18V, LM = 0.5mH, RCS = 0.75Ω, VOUT = 13V, NP = 68, NS =12, NA = 17, TA = 25°C, unless otherwise specified,12V0.4A application) PARAMETER SYMBOL TEST CONDITIONS MIN TYP MAX UNIT 2 2.25 3 µs CS Short Detection Threshold 0.1 0.15 V CS Open Threshold Voltage 1.75 V Abnormal OCP Blanking Time 190 ns Inductance Short CS Threshold Voltage 1.75 V Thermal Shutdown Temperature 135 ˚C Thermal Hysteresis 20 ˚C Protection CS Short Waiting Time Vo Short Detection Threshold VFBUVLO 0.28 V Line UVLO IFBUVLO 0.2 mA 20 µA 2.4 mA 3 V 3.3 µs Line UVLO Hysteresis Line OVP IFBOVP VFB Over Voltage Protection Valley Detection Valley Detection Time Window Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. VCOMP = 0.45V -5- www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 FUNCTIONAL BLOCK DIAGRAM Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. -6- www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 FUNCTIONAL DESCRIPTION ACT412 is a high performance peak current mode low-voltage PWM controller IC. The controller includes the most advance features that are required in the adaptor applications up to 36 Watt. Unique fast startup, frequency fold back, QR switching technique, accurate OLP, low standby mode operation, external compensation adjustment, short winding protection, OCP, OTP, OVP and UVLO are included in the controller. transformer secondary and auxiliary turns, and VD is the rectifier diode forward drop voltage at approximately 0.1A bias. Constant Power (CP) Mode Operation When the secondary output current reaches a level set by the internal current limiting circuit, the ACT412 enters current limit condition and causes the secondary output voltage to drop. As the output voltage decreases, so does the flyback voltage in a proportional manner. An internal current shaping circuitry adjusts the switching frequency and current limit threshold slowly based on the flyback voltage so that the transferred power is fixed to the output voltage, resulting in a constant power at secondary side output power profile. Through correctly setting K1, K2, the energy transferred to the output during each switching cycle is ½(LP × ILIM^2) , where LP is the transformer primary inductance, ILIM is the primary peak current, Formula can be present as below: Startup Startup current of ACT412 is designed to be very low so that VDD could be charged to VDDON threshold level and device starts up quickly. A large value startup resistor can therefore be used to minimize the power loss yet reliable startup in application. For a typical AC/DC adaptor with universal input range design, two 1MΩ, 1/8 W startup resistors could be used together with a VDD capacitor(4.7uF) to provide a fast startup and yet low power dissipation design solution. During startup period, the IC begins to operate with minimum Ippk to minimize the switching stresses for the main switch, output diode and transformers. And then, the IC operates at maximum power output to achieve fast rise time. After this, VOUT reaches about 90% VOUT , the IC operates with a ‘soft-landing’ mode (decrease Ippk) to avoid output overshoot. P OUTCP (2) Loop Compensation The ACT412 allows external loop compensation by connecting a capacitor to extend its applications, especially with different VOUT in a wide output power range. Primary Inductance Compensation The ACT412 integrates a built-in primary inductance compensation circuit to maintain constant OLP despite variations in transformer manufacturing. The compensated ranges is +/-7%. (1) where RFB1 (R5) and RFB2 (R6) are top and bottom feedback resistor, NS and NA are numbers of ActivePSRTM is a trademark of Active-Semi. ) 2 × η × K 2 f SW In no load standby mode, the ACT412 oscillator frequency is further reduced to a minimum frequency while the current pulse is reduced to a minimum level to minimize standby power. The actual minimum switching frequency is programmable with an output preload resistor. This error signal is then amplified by the internal error amplifier. When the secondary output voltage is above regulation, the error amplifier output voltage decreases to reduce the switch current. When the secondary output voltage is below regulation, the error amplifier output voltage increases to ramp up the switch current to bring the secondary output back to regulation. The output regulation voltage is determined by the following relationship: Innovative PowerTM _ TH Standby (No Load) Mode In constant voltage operation, the ACT412 senses the output voltage at FB pin through a resistor divider network R5 and R6 in Figure 2. The signal at FB pin is pre-amplified against the internal reference voltage, and the secondary side output voltage is extracted based on Active-Semi's proprietary filter architecture. R FB 1 N ) × S - VD R FB 2 NA 1 × L p × ( K 1V CS 2 where fSW is the switching frequency. The constant power operation typically extends down to 20% of nominal output voltage regulation. Constant Voltage (CV) Mode Operation VOUTCV = 2 . 20 V × ( 1 + = Primary Inductor Current Limit Compensation The ACT412 integrates a primary inductor peak -7- www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 FUNCTIONAL DESCRIPTION CONT’D current limit compensation circuit to achieve constant power over wide line and wide load range. identified. There is a startup phase in the autorestart mode. After this startup phase the conditions are checked whether the failure is still present. Normal operation proceeds once the failure mode is removed. Otherwise, new startup phase will be initiated again. Frequency Fold-back When the load drops to 75% of full load level, ACT412 starts to decrease the switching frequency, which is proportional to the load current ,to improve the efficiency of the converter as show in Functional Block Diagram. PROTECTION FUNCTIONS FAILURE CONDITION PROTECTION MODE VDD Over Voltage VDD > 20.5V (4 duty cycle) Auto Restart VFB Over Voltage VFB > 3V (4 duty cycle) Auto Restart Valley Switching Over Temperature T > 135˚C Auto Restart ACT412 employed valley switching from medium load to heavy load to reduce switching loss and EMI. After the switch is turned off, the ringing voltage from the auxiliary winding is applied to the VFB pin through feedback network R5, R6. Internally, the VFB pin is connected to an zerocrossing detector to generate the switch turn on signal when the conditions are met. In light load, the frequency fold back scheme starts to take control to determine the switch turn on signal, so thus the switching frequency. Short Winding/ Short Diode VCS > 1.75V Auto Restart Over Load IPK = ILIMIT Auto Restart Output Short Circuit VFB < 0.28V Auto Restart Open Loop No switching for 4 cycle Auto Restart VCC Under Voltage VCC < 6.8V Auto Restart This enables the application to meet all latest green energy standards. The actual minimum switching frequency is programmable with a small dummy load (while still meeting standby power). Figure 1: To reduce the power loss during fault mode, the startup delay control is implemented. The startup delay time increases over lines. Valley Switching at heavy load Short Circuit Protection Vdrain_gnd Mosfet When the secondary side output is short circuited, the ACT412 enters hiccup mode operation. This hiccup behavior continues until the short circuit is removed. DC voltage FB Over Voltage Protection Possible Valley turn on Ton The ACT412 includes output over-voltage protection circuitry, which shuts down the IC when the output voltage is 40% above the normal regulation voltage 4 consecutive switching cycles. The ACT412 enters hiccup mode when an output over voltage fault is detected. t T VDD Over Voltage Protection Protection Features ACT412 can monitor the converter output voltage. The voltage generated by the auxiliary winding tracks converter’s output voltage through VDD, which is in proportion to the turn ratio (VOUT+VDIODE) хNA/NS. When the VOUT is abnormally higher than design value for four consecutive cycles, IC will The ACT412 provides full protection functions. The following table summarizes all protection functions. Auto-Restart Operation ACT412 will enter auto-restart mode when a fault is Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. -8- www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 TYPICAL APPLICATION CONT’D enter the restart process. A counter is used to reduce sensitivity to noise and prevent the auto start unnecessary. Open Loop Protection ACT412 is able to protect itself from damage when the control loop is open. The typical open loop condition includes either VFB floating or RFB5 open. Over Temperature Shutdown The thermal shutdown circuitry detects the ACT412 die temperature. The threshold is set at typical 135˚C. When the die temperature rises above this threshold (135˚C) the ACT412 is disabled and remains disabled until the die temperature falls below 115˚C, at which point the ACT412 is reenabled. Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. -9- www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 TYPICAL APPLICATION CONT’D Design Example The design example below gives the procedure for a DCM fly back converter using an ACT412. Refer to Application Circuit Figure 2, the design for an adapter application starts with the following specification: Input Voltage Range 90VAC - 265VAC, 50/60Hz Output Power, PO 5W Output Voltage, VOUTCV 0.4A CC Current, IOUTMAX 1.8A System Efficiency CV, η 0.75 I IN = Since a bridge rectifier and bulk input capacitors are used, the resulting minimum and maximum DC input voltages can be calculated: = VIN ( MAX = 1 2 POUT ( - tC ) 2 fL η × CIN 1 2 ×5 ×( - 3 .5 ms ) 2 × 2 47 2 × 85 ≈90V 0 .75 × 2 × 6 .8 μF ) DC = 2 × VIN ( MAX ) AC 2 × ( 265 V AC ) = 375 V (3) ActivePSRTM is a trademark of Active-Semi. P OUT V INDC 5 × 0 . 75 90 _ FL _ MIN × η (5) ≈ 75 mA I ppk _ FL = 2 × LI N _ FL = D FL 2 × 75 = 375 mA 0 .4 (4) - 10 - (6) The primary inductance of the transformer: Lp = V INDC I ppk _ MIN _ FL D FL × fs (7) 90 × 0 . 4 = ≈ 0 . 74 mH 375 mA × 130 k The primary turns on time at full load: TON _ FL = Lp I ppk _ FL V INDC (8) _ MIN 0 . 74 mH × 375 mA = = 3 . 08 μ s 90 The ringing periods from primary inductance with mosfet Drain-Source capacitor: TRINGING _ MAX = 2 π Lp _ MAX C DS _ MAX = 2 × 3 .14 × 0 .73 mH × (1 + 7 %) × 100 PF = 1 .76 μs (9) Design only an half ringing cycle at maximum load in minimum low line, so secondly reset time: TRST = TSW - TON _ FL - 0.5TRINGING _ MAX = 1 / 130 kHz - 3.08 μs - 0.5 × 1.76 μs = 3.73 μs (10) Base on conservation of energy and transformer transform identity, the primary to secondary turns ratio NP/NS: V IN _ MIN NP T = ON × NS T RST V OUT + V D (11) 3 . 08 90 = × = 5 . 53 3 . 73 13 + 0 . 45 Where ŋ is the estimated circuit efficiency, fL is the Innovative PowerTM = _ FL The input primary peak current at full load: The operation for the circuit shown in Figure 1 is as follows: the rectifier bridge D1-D4 and the capacitor C1/C2 convert the AC line voltage to DC. This voltage supplies the primary winding of the transformer T1 and the startup resistor R7/R8 to VDD pin of ACT412 and C4. The primary power current path is formed by the transformer’s primary winding, the mosfet, and the current sense resistor R9. The resistors R3, R2, diode D5 and capacitor C3 create a snubber clamping network that protects Q1 from voltage spike from the transformer primary winding leakage inductance. The network consisting of capacitor C4, diode D6 and resistor R4 provides a VDD supply voltage for ACT412 from the auxiliary winding of the transformer. The resistor R4 is optional, which filters out spikes and noise to makes VDD more stable. C4 is the decoupling capacitor of the supply voltage and energy storage component for startup. During power startup, the current charges C4 through startup resistor R7/R8 from the rectified high voltage. The diode D8 and the capacitor C5/C6 rectify filter the output voltage. The resistor divider consists of R5 and R6 programs the output voltage. 2 2VINAC _ MIN The full load system duty cycle is set to be 40% at low line voltage 85VAC and the circuit efficiency is estimated to be 75%. Then the average input current at full load is: 12V Full Load Current, IOUTFL VINDC _ MIN = line frequency, tC is the estimated rectifier conduction time, CIN is empirically selected to be 2х6.8µF electrolytic capacitors. The auxiliary to secondary turns ratio NA/NS: NA V + VD ' 18 + 0 . 45 = DD = = 1 . 37 N S VOUT + V D 13 + 0 . 45 (12) www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 TYPICAL APPLICATION CONT’D An EE16 core is selected for the transformer. From the manufacture’s catalogue recommendation, the core with an effective area AE is 19.2mm2 .The turn of the primary winding is: NP ≥ Ilim × Lp _ max AE × Bmax = 0.75 × 0.00073 = 95T 19 .2 × 3000 × 10 −10 I lim = 2 × I p _ FL = 2 × 375 mA ≈ 750 mA (13) (14) The turns of secondary and auxiliary winding can be derived accordingly: Ns = Np / NA = Np NS = 95 / 5 . 53 ≈ 17 T (15) NA × N s = 1 . 4 × 17 ≈ 24 T NS down the turn ratio and inductance. N p = 68 T , N s = 12 T , N A = 17 T , L p = 0 . 5 mH (21) PCB Layout Guideline Good PCB layout is critical to have optimal performance. Decoupling capacitor (C4) and feedback resistor (R5/R6) should be placed close to VDD and FB pin respectively. There are two main power path loops. One is formed by C1/C2, primary winding, Mosfet transistor and current sense resistor (R9). The other is secondary winding, rectifier D8 and output capacitors (C5/C6). Keep these loop areas as small as possible. Connecting high current ground returns, the input capacitor ground lead, and the ACT412 GND pin to a single point (star ground configuration). Determining the value of the current sense resistor (R9) uses the peak current in the design. Since the ACT412 internal current limit is set to 1V, the design of the current sense resistor is given by: R CS = V CS 1 = ≈ 1 . 3 .Ω I lim 0 . 75 (16) The voltage feedback resistors are selected according to frequency at full load. The design frequency at full load is given by: fs = Np Ns × R fb 1 × R fb 2 VO + V D × V R fb 1 + R fb 2 L p × cs × K f R cs _ sw (17) The design Vo is given by: Vo = (1 + R fb1 N ) × s × VFB − VD R fb 2 Na (18) Where k is IC constant and K=0.0000065, then we can get the value: R fb 1 = 45 . 3 K , R fb 2 = 6 . 9 K (19) When selecting the output capacitor, a low ESR electrolytic capacitor is recommended to minimize ripple from the current ripple. The approximate equation for the output capacitance value is given by: COUT = IOUT 1.8 = = 327 μF fsw ×VRIPPLE 110k × 50mV (20) Two 330µF electrolytic capacitors are used to keep the ripple small. In fact, consider of transformer production, we scale Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. - 11 - www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 Figure 2: ACT412, Universal VAC Input, 12V/400mA Output Charger V-I Characteristic vs. VIN (25˚C) 16 High Limit 115V 12 Low Limit 10 V 90 Output Voltage (V) 14 230V 8 264V 6 4 2 0 0 300 600 900 1200 1400 Output Current (mA) Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. - 12 - www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 Table 2: ACT412 Bill of Materials ITEM REFERENCE 1 U1 QTY MANUFACTURER IC, ACT412,SOT23-6 2 DESCRIPTION 1 Active-Semi. C1,C2 Capacitor, Electrolytic, 6.8µF/400V, 10x12mm 2 KSC 3 C3 Capacitor, Ceramic, 1000pF/500V, 0805,SMD 1 POE 4 C4 Capacitor, Electrolytic,4.7µF/35V,5x11mm 1 KSC 5 C5,C6 Capacitor, Electrolytic, 330µF/16V, 8x11.5mm 2 KSC 6 C8 Capacitor, Ceramic, 0.1µF/25V, 0805,SMD 1 POE 7 C9 Capacitor, Ceramic, 1000pF/100V, 0805,SMD 1 POE 8 C10 Capacitor, Ceramic, 200pF/50V, 0805,SMD 1 POE 9 CY1 Safety Y1,Capacitor,1000pF/400V,Dip 1 UXT 10 D1-D4 Diode,Rectifier,1000V/1A,1N4007, DO-41 4 Good-Ark 11 D5 Fast Recovery Rectifier, RS1M,1000V/1.0A, RMA 1 PANJIT 12 D6 Fast Recovery Rectifier,RS1D,200V/1.0A,SMA 1 PANJIT 13 D7 NC 14 D8 Diode, schottky, 100V/3A, SB3100, DO-47 1 Good-Ark 15 L1 Axial Inductor, 1.5mH, 5*7,Dip 1 SoKa 16 L2 Axial Inductor, 0.55*5T, 5*7,Dip 1 SoKa 17 Q1 Mosfet Transistor, 4N60,TO-220 1 Infineon 18 PCB1 PCB, L*W*T=52.2x30x1.6mm,Cem-1,Rev:A 1 Jintong 19 FR1 Fuse,1A/250V 1 TY-OHM 20 R1 Chip Resistor, 51Ω, 0805, 5% 1 TY-OHM 21 R2 Chip Resistor, 510KΩ, 1206, 5% 1 TY-OHM 22 R3 Chip Resistor, 100Ω, 0805, 5% 1 TY-OHM 23 R4,R13 Chip Resistor, 22Ω, 0805, 5% 2 TY-OHM TY-OHM 24 R5 Chip Resistor, 45.3KΩ, 0805,1% 1 25 R6 Chip Resistor, 6.9KΩ, 0805, 1% 1 TY-OHM 26 R7,R8 Chip Resistor, 1.5MΩ, 0805 , 5% 2 TY-OHM 27 R9 Chip Resistor, 0.75Ω, 1206,1% 1 TY-OHM 28 R11 Chip Resistor, 6.8KΩ, 0805, 5% 1 TY-OHM 29 R12 Chip Resistor, 3KΩ, 0805 , 5% 1 TY-OHM 30 R14 Chip Resistor, 390Ω, 0805 , 5% 1 TY-OHM 31 R15 Chip Resistor, 100KΩ, 0805 , 5% 1 TY-OHM 32 T1 Transformer, Lp=0.5mH, EE16 1 Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. - 13 - www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 TYPICAL PERFORMANCE CHARACTERISTICS Startup Supply Current vs. Temperature VDD ON/OFF Voltage vs. Temperature 10.5 9.5 8.5 VDDOFF 7.5 6.5 0 40 80 5 4 -40 0 40 80 120 Temperature (°C) Temperature (°C) Supply Current at Operation/Fault Mode vs. Temperature Maximum/Minimum Switching Frequency vs. Temperature 0.5 0.4 Fault Mode 0.3 0.2 -40 0 40 80 150 FMAX 100 50 FMIN 0 -40 120 0 40 80 120 Temperature (°C) Temperature (°C) VCS Voltage vs. Temperature VFB Threshold Voltage vs. Temperature 1.5 VFB Threshold Voltage (V) VCS_Open VCS Voltage 1 0.5 VCS_Short 2.5 ACT412-006 ACT412-005 2 VREF 2 1.5 0 -40 ACT412-004 ACT412-003 Operation Mode Supply Current (mA) 6 120 0.6 VCS Voltage (V) 7 3 -40 Maximum Switching Frequency (KHz) VDDON and VDDOFF (V) 11.5 Startup Supply Current (µA) VDDON 12.5 ACT412-002 8 ACT412-001 13.5 0 40 80 120 -40 Temperature (°C) Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. 0 40 80 120 Temperature (°C) - 14 - www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 TYPICAL PERFORMANCE CHARACTERISTICS VCOMP Voltage vs. Temperature VDDON and VDDOFF (V) ACT412-007 VMAX 4 3 2 1 VMIN 0 -40 0 40 80 120 Temperature (°C) Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. - 15 - www.active-semi.com Copyright © 2013 Active-Semi, Inc. ACT412 Rev 1, 30-Oct-13 PACKAGE OUTLINE SOT23-6 PACKAGE OUTLINE AND DIMENSIONS Active-Semi, Inc. reserves the right to modify the circuitry or specifications without notice. Users should evaluate each product to make sure that it is suitable for their applications. Active-Semi products are not intended or authorized for use as critical components in life-support devices or systems. Active-Semi, Inc. does not assume any liability arising out of the use of any product or circuit described in this datasheet, nor does it convey any patent license. Active-Semi and its logo are trademarks of Active-Semi, Inc. For more information on this and other products, contact [email protected] or visit http://www.active-semi.com. is a registered trademark of Active-Semi. Innovative PowerTM ActivePSRTM is a trademark of Active-Semi. - 16 - www.active-semi.com Copyright © 2013 Active-Semi, Inc.