Fujitsu MB39A104 - Manual

MB39A104 5 ■ ABSOLUTE MAXIMUM RATINGS * : The packages are mounted on the epoxy board (10 cm × 10 cm). WARNING: Semiconductor devices can be permanently damaged by application of stress (voltage, current, temperature, etc.) in excess of absolute maximum ratings. Do not exceed these ratings. ■ RECOMM...

MB39A104 6 ■ ELECTRICAL CHARACTERISTICS (VCC = VCCO = 12 V, VREF = 0 mA, Ta = + 25 ° C) (Continued) Parameter Symbol Pin No Conditions Value Unit Min Typ Max 1.Reference voltage block [REF] Output voltage V REF 17 Ta = + 25 ° C 4.95 5.00 5.05 V Output voltage temperature variation ∆ V REF / V REF 17...

MB39A104 8 ■ TYPICAL CHARACTERISTICS (Continued) Ta = + 25 ° C CTL = 5 V 10 8 6 4 2 0 0 5 10 15 20 Ta = + 25 ° C CTL = 5 V VREF = 0 mA 10 8 6 4 2 0 0 5 10 15 20 Ta = + 25 ° C VCC = 12 V CTL = 5 V 10 8 6 4 2 0 0 5 10 15 20 25 30 35 VCC = 12 V CTL = 5 V VREF = 0 mA 2.0 1.5 1.0 0.5 0.0 − 0.5 − 1.0 − 1....

MB39A104 10 (Continued) − + + + 10 (15) 11 (14) 9 (16) IN OUT Error Amp1 (Error Amp2) 1 µ F 1.24 V 10 k Ω 2.4 k Ω 240 k Ω 10 k Ω 40 30 20 10 0 − 10 − 20 − 30 − 40 180 90 0 − 90 − 180 100 1 k 10 k 100 k 1 M 10 M Ta = + 25 ° C VCC = 12 V A V ϕ 1000 800 600 400 200 0 740 − 40 − 20 0 20 40 60 80 100 Err...

MB39A104 11 ■ FUNCTIONS 1. DC/DC Converter Functions (1) Reference voltage block (REF) The reference voltage circuit generates a temperature-compensated reference voltage (5.0 V Typ) from thevoltage supplied from the power supply terminal (pin 7). The voltage is used as the reference voltage for the...

MB39A104 12 2. Control Function When CTL terminal (pin 24) is “L” level, IC becomes the standby mode. The power supply current is 10 µ A (Max) at the standby mode. On/Off Setting Conditions 3. Protective Functions (1) Timer-latch overcurrent protection circuit block (OCP) The timer-latch overcurrent...

MB39A104 13 ■ SETTING THE OUTPUT VOLTAGE ■ SETTING THE TRIANGULAR OSCILLATION FREQUENCY The triangular oscillation frequency is determined by the timing capacitor (C T ) connected to the CT terminal (pin 13), and the timing resistor (R T ) connected to the RT terminal (pin 12). Moreover, it shifts m...

MB39A104 14 ■ SETTING THE SOFT-START AND DISCHARGE TIMES To prevent rush currents when the IC is turned on, you can set a soft-star t by connecting soft-start capacitors(C S1 and C S2 ) to the CS1 terminal (pin 11) for channel 1 and the CS2 terminal (pin 14) for channel 2, respectively. When CTL ter...

MB39A104 15 − + + 16 9 10 15 R1 R2 ( − INE2) CS1 (CS2) C S1 (C S2 ) − INE1 10 µ A FB1 (FB2) VREF V O Error Amp UVLO 1.24 V 11 14 L priority CH ON/OFF signalL : ON, H : OFF • Soft-Start Circuit

MB39A104 16 ■ TREATMENT WITHOUT USING CS TERMINAL When not using the soft-start function, open the CS1 terminal (pin 11) and the CS2 terminal (pin 14) . 11 CS1 14 CS2 “OPEN” “OPEN” • Without Setting Soft - Start Time

MB39A104 17 ■ ABOUT TIMER-LATCH PROTECTION CIRCUIT 1. Setting Timer-Latch Overcurrent Protection Detection Current The overcurrent protection circuit is actuated upon completion of the soft-start period. When an overcurrentflows, the circuit detects the increase in the voltage between the FET’s drai...

MB39A104 18 Overcurrent Protection Circuit: Range of Operation When an overcurrent flow occurs, if the increased voltage between the drain and source of the FET is detectedby means of the external FET (Q1) resistor, operational stability is lost when the external FET (Q1) ON intervaldetermined by th...

MB39A104 19 2. Setting Time Constant for Timer-Latch Short-Circuit Protection Circuit Each channel uses the short-circuit detection comparator (SCP Comp.) to always compare the error amplifier ′ s output level to the reference voltage (3.1 V Typ).While DC/DC conver ter load conditions are stable on ...

MB39A104 20 ■ TREATMENT WITHOUT USING CSCP TERMINAL When not using the timer-latch short-circuit protection circuit, connect the CSCP terminal (pin 8) to GND withthe shortest distance. ■ RESETTING THE LATCH OF EACH PROTECTION CIRCUIT When the overcurrent, or short-circuit protection circuit detects ...

MB39A104 21 ■ I/O EQUIVALENT CIRCUIT 7 18 +− 1.24 V 17 VREF VCC GND 77.8 k Ω 24.8 k Ω CTL GND 72 k Ω 104 k Ω 24 CSX VCC GND VREF (5.0 V) RT GND (3.1 V) 12 +− 1.35 V VCC CSCP 2 k Ω GND VREF (5.0 V) 8 CT GND (3.1 V) 13 − INEX CSX GND VCC VREF (5.0 V) FBX 1.24 V ILIMX GND GNDO VCCO VSX VCC DTCX GND VCC...

MB39A104 22 ■ APPLICATION EXAMPLE A B B + + A + + R10 R11 R9 68 k Ω 220 k Ω C16 0.1 µ F C12 1000 pF C14 1000 pF C21 1000 pF 150 k Ω 56 k Ω R15 R16 R14 68 k Ω 220 k Ω R13 C17 0.1 µ F 13 k Ω 100 k Ω R8 VIN (7 V to 19 V) R1 24 k Ω C1 100 pF C20 0.1 µ F C10 0.1 µ F R5 C6 10 µ F C8 82 µ F C7 10 µ F C11 0...

MB39A104 23 ■ PARTS LIST Note : TOSHIBA : TOSHIBA Corporation ROHM : ROHM Co., Ltd SANYO : SANYO Electric Co., Ltd.TDK : TDK Corporation SUMIDA : SUMIDA Electric Co., Ltd.ssm : SUSUMU Co., Ltd. COMPONENT ITEM SPECIFICATION VENDOR PARTS No. Q1, Q2 Pch FET VDS = − 30 V, ID = − 6 A TOSHIBA TPC8102 D1, ...

MB39A104 24 ■ SELECTION OF COMPONENTS • Pch MOS FET The P-ch MOSFET for switching use should be rated for at least 20% more than the maximum input voltage. Tominimize continuity loss, use a FET with low R DS(ON) between the drain and source. For high input voltage and high frequency operation, on/of...

MB39A104 25 The above power dissipation figures for the TPC8102 are satisfied with ample margin at 2.4 W (Ta = + 25 ° C) . CH2 Input voltage V IN (Max) = 19 V output voltage V O = 3.3 V, drain current I D = 3 A, Oscillation frequency f OSC = 500 kHz, L = 15 µ H, drain-source on resistance R DS (ON) ...

MB39A104 26 The above power dissipation figures for the TPC8102 are satisfied with ample margin at 2.4 W (Ta = + 25 ° C) . • Inductors In selecting inductors, it is of course essential not to apply more current than the rated capacity of the inductor,but also to note that the lower limit for ripple ...

MB39A104 30 • Smoothing Capacitor The smoothing capacitor is an indispensable element for reducing ripple voltage in output. In selecting a smooth-ing capacitor it is essential to consider equivalent series resistance (ESR) and allowable ripple current. HigherESR means higher ripple voltage, so that...

MB39A104 32 ■ REFERENCE DATA (Continued) Vin = 7 VVin = 10 V Vin = 19 V Vin = 12 V 100 90 80 70 60 50 40 30 10 m 100 m 1 10 Vin = 7 VVin = 10 V Vin = 19 V Vin = 12 V 100 90 80 70 60 50 40 30 10 m 100 m 1 10 TOTAL efficiency η ( % ) Input voltage V IN (V) TOTAL Efficiency vs. Input Voltage Each CH ef...

MB39A104 34 ■ USAGE PRECAUTION •••• Printed circuit board ground lines should be set up with consideration for common impedance. •••• Take appropriate static electricity measures. • Containers for semiconductor materials should have anti-static protection or be made of conductive material.• After mo...

MB39A104 35 ■ PACKAGE DIMENSIONS 24-pin plastic SSOP (FPT-24P-M03) Note 1) *1 : Resin protrusion. (Each side : + 0.15 (.006) MAX) . Note 2) *2 : These dimensions do not include resin protrusion.Note 3) Pins width and pins thickness include plating thickness.Note 4) Pins width do not include tie bar ...

MB39A104 FUJITSU LIMITED All Rights Reserved. The contents of this document are subject to change without notice. Customers are advised to consult with FUJITSU salesrepresentatives before ordering.The information, such as descriptions of function and applicationcircuit examples, in this document are...