AP3842/3/4/5 500KHZ AP3842 AP3844 AP3843 AP3845 AP384X 1250C 0VV04V 0VPIN30

High Performance Current Mode PWM Controller Features · · · · · · · ·

AP3842/3/4/5 AP3842/3/4/5 High Performance Current Mode PWM Controller Features · · · · · · · · · · · General Description Optimized for Off-Line and DC to DC Converters Low Start-Up Current (0.5mA) Automatic Feed Forward Compensation Pulse-by-Pulse Current Limiting Enhanced Load Response Characteristics Under-Voltage Lockout (UVLO) with Hysteresis Double Pulse Suppression High Current Totem Pole Output Internally Trimmed Bandgap Reference Current Mode Operation to 500KHZ 500KHZ Low Ro Error Amplifier The AP3842/3/4/5 AP3842/3/4/5 family of control ICs provides the necessary features to implement off-line or DC to DC fixed frequency current mode control schemes with a minimal external parts count. Internally implemented circuits include under voltage lockout featuring start-up current less than 0.5 mA, a precision reference trimmed for accuracy at the error amp input, logic to insure latched operation, a PWM comparator which also provides current limit control, and a totem pole output stage designed to source or sink high peak current. The output stage, suitable for driving N-Channel MOSFETs, is low in the off-state. Pin Connections Differences between members of this family are the under-voltage lockout thresholds and maximum duty cycle ranges. The AP3842 AP3842 and AP3844 AP3844 have UVLO thresholds of 16V(on) and 10V(off), ideally suited for off-line applications. The corresponding thresholds for the AP3843 AP3843 and AP3845 AP3845 are 8.5V and 7.6V. The AP3842 AP3842 and AP3843 AP3843 can operate to duty cycles approaching 100%. A range of the zero to < 50% is obtained by the AP3844 AP3844 and AP3845 AP3845 by the addition of an internal toggle flip flop which blanks the output off every other clock cycle. PDIP-8L, SOP-8L Top View COMP. 1 8 VREF VFB 2 7 VI ISENSE 3 6 OUTPUT RT/CT 4 5 GROUND Ordering Information AP 384X X X X Part No. 2:3842 3:3843 4:3844 5:3845 Package S8:SOP-8L N8:PDIP-8L Lead Free Packing Blank: Tube Blank : Normal L : Lead Free Package A : Taping This datasheet contains new product information. Anachip Corp. reserves the rights to modify the product specification without notice. No liability is assumed as a result of the use of this product. No rights under any patent accompany the sale of the product. Rev.A3 Feb.10, 2004 1/8 AP3842/3/4/5 AP3842/3/4/5 High Performance Current Mode PWM Controller Block Diagram ( toggle flip flop used only in AP3844 AP3844 and AP3845 AP3845 ) Vi 7 36V GROUND 5 UVLO 16V 2.50V RT/CT 4 ERROR AMP. VREF GOOD LOGIC 6 OUTPUT T 2R VFB CURRENT SENSE VREF 5V 50mA INTERNAL BIAS OSC. 2 COMP 8 5V REF S/R S R 1 R 1V CURRENT SENSE COMPARATOR 3 PWM LATCH AP384X AP384X Absolute Maximum Ratings Symbol Vi Vi Io Eo Ptot Ptot Tstg TL Parameter Supply Voltage (low impedance source) Supply Voltage (li < 30mA) Output Current Output Energy (capacitive load) Analog Inputs (pins2,3) Error Amplifier Output Sink Current Power Dissipation at Tamb 500C (PDIP8) Power Dissipation at Tamb 250C (SOP8) Storage Temperature Range Lead Temperature (soldering 10s) Value 36 Self Limiting ± 0.7 5 -0.3 to 5.5 10 1.25 800 -65 to 150 260 Unit V A J V mA W mW o C o C *Notes: 1. All voltages are with respect to pin 5, all currents are positive into the specified terminal. Electrical Characteristics (Unless otherwise stated, these specifications apply for Symbol Parameter o 0Tamb70 C for AP384X AP384X ; Vi = 15V(note 5); RT = 10K;CT = 3.3nF) Test Conditions AP384X AP384X Min. Typ. Max. Unit REFERENCE SECTION VREF Output Voltage VREF Line Regulation VREF Load Regulation VREF/T Temperature Stability Total Output Variation eN ISC Tj = 250C I0=1mA 4.90 5.00 5.10 V 12VVi25V 2 20 mV 1mAIo20mA 3 25 mV (Notes 2) 0.2 0.4 mV/0C Line, Load, Temperature (Notes 2) 4.82 5.18 V 10Hzf10KHz Tj=250C (Notes V 50 Output Noise Voltage 2) Long Term Stability Tamb=1250C 1250C, 1000Hrs (Notes 2) 5 25 mV Output Short Circuit current -85 -120 mA Anachip Corp. www.anachip.com.tw Rev.A3 Feb.10, 2004 2/8 AP3842/3/4/5 AP3842/3/4/5 High Performance Current Mode PWM Controller Electrical Characteristics(Continued) (Unless otherwise stated, these specifications apply for Symbol Parameter OSCILLATOR SECTION fs Oscillator Frequency Voltage Stability Temperature Stability V4 Amplitude Discharge Current ERROR AMP SECTION V2 Feedback Input Voltage Ib Input Bias Current AVOL B Unity Gain Bandwidth Supply Voltage Rejection SVRR Ratio IO Output Sink Current IO Output Source Current VOUT High VOUT Low CURRENT SENSE SECTION Gv Gain V3 Maximum Input Signal Supply Voltage Rejection SVRR Ratio Ib Input Bias Current Delay to Output OUTPUT SECTION VOL Output Low Level VOH Output High Level Tr Rise Time Tf Fall Time VOLS UVLO Saturation UNDER-VOLTAGE LOCKOUT SECTION o 0Tamb70 C for AP384X AP384X ; Vi = 15V(note 5); RT = 10K;CT = 3.3nF) Test Conditions Tj=250C (Notes 6, 7) 12VVi25V TMINTambTMAX (Notes 2) VPIN4 Peak to Peak Tj=250C VPIN4=2V VPIN1=2.5V VFB=5V 0VV04V 0VV04V Tj=25oC AP384X AP384X Min. Typ. Max. 49 8.8 KHz % % V mA 2.42 2.50 2.58 -0.1 -2 65 90 0.7 1 V A dB MHz 7.8 52 0.2 0.5 1.6 8.3 12VVi25V 60 70 dB VPIN2=2.7V VPIN1=1.1V VPIN2=2.3V VPIN1=5V VPIN2=2.3V; RL=15K to ground VPIN2=2.7V; RL=15K to pin 8 2 -0.5 5 6 -0.8 7 0.8 1.1 mA mA V V (Notes3&Notes4) VPIN1=5V (Notes3) 2.85 0.9 3 1 3.15 1.1 V/V V 12Vi25V (Notes3) 70 ISINK= 20mA ISINK= 200mA ISOURCE= 20mA ISOURCE= 200mA Tj=250C CL=1nF (Notes2) Tj=250C CL=1nF (Notes2) Vcc = 6V ; Isink = 1mA A ns 0.1 1.6 13.5 13.5 50 50 0.1 0.4 2.2 150 150 1.1 V V V V ns ns V 17.5 9 11.5 8.2 V V V V 50 0 % % % 0.3 13 12 -10 300 0.5 mA 12 36 17 mA V 3842/4 3843/5 3842/4 3843/5 Maximum Duty Cycle 14.5 7.8 8.5 7.0 16 8.4 10 7.6 3842/3 3844/5 Min Operating Voltage After Turn-on PWM SECTION 94 47 96 48 Minimum Duty Cycle TOTAL STANDBY CURRENT Start-up Current Ii Viz Operating Supply Current Zener Voltage dB -2 150 Start Threshold Ist 55 1 Unit Vi=14V,3842/4 ; Vi=6.5V 3843/5 VPIN2=VPIN3=0V Ii=25mA Anachip Corp. www.anachip.com.tw 30 Rev.A3 Feb.10, 2004 3/8 AP3842/3/4/5 AP3842/3/4/5 High Performance Current Mode PWM Controller Notes2.These parameters, although guaranteed, are not 100% tested in production. 3.Parameter measured at trip point of latch with VPIN2=0. 4.Gain defined as: VPIN1 ; 0VPIN30 0VPIN30.8V A= VPIN3 5.Adjust Vi above the start threshold before setting at 15V. 6.Output frequency equals oscillator frequency for the AP3842 AP3842 and AP3843 AP3843. 7.Output frequency is one and half oscillator frequency for the AP3844 AP3844 and AP3845 AP3845. Figure 1 : Error Amp Configuration. 2.5V 0.8 mA VFB Zf 2 COMP 1 Zf Error amp can source or sink up to 0.5mA Figure 2 : Under Voltage Lockout. Vi ICC ON/OFF COMMAND TO REST OF IC 7 AP3842 AP3842 AP3843 AP3843 AP3844 AP3844 AP3845 AP3845 VON 16V 8.4V VOFF 10V