ML7900 SERIES 3-TERMINAL NEGATIVE VOLTAGE REGULATOR The ML7900 series are 3-Terminal Negative Voltage Regulators. These negative regulators are intended as complements to the popular ML7800 series of positive voltage regulations, and they are available in the same voltage options from -5V to -24V. The ML7900 series employ internal current-limiting. safe-area protection , and thermal shutdown, making them virtually indestructible. ■ Package Outline TO-220 (7900A) TO-220F (7900FA) 1. OUT 2. IN 3. COMMON 32 (Ta=25℃) ABSOLUTE MAXIMUM RATINGS PARAMETER Input Voltage Storage Temperature Range Maximum Rating SYMBOL VIN UNIT ML7905 to ML7909 -35 ML7912 to ML7920 -35 ML7924 -40 V -40 to +125 Tstg Operating Temperature Range Power Dissipation 1 ℃ Operating Junction Temperature Tj -30 to +125 Operating Ambient Temperature Topr -30 to +75 ℃ 15(Tc≦45℃ ) PD W THERMAL RESISTANCE Thermal Resistance Junction-to-Ambient Temperature Θ ja 60 Junction-to-Case Θ jc 5 ELECTRICAL CHARACTERISTICS PARAMETER (Tj=25℃,C1=0.33μF,Co=0.1μF) TEST CONDITIONS SYMBOL ℃/W Measurement is to be conducted in pulse testing. MIN. TYP. MAX. UNIT ML7905A / ML7905FA Output Voltage Vo VIN=-10V Io=0.5A -4.8 -5.0 -5.2 V Quiescent Current IQ VIN=-10V Io=0mA - 2.2 5.0 mA Load Regulation ΔVo Io VIN=-10V Io=0.005A to 1.5A - 50 100 mV Line Regulation ΔVo Vin - 12.5 100 mV VIN=-7 to -25V Io=0.5A ein=2Vp-p Ripple Rejection RR VIN=-10V Io=0.5A Output Noise Voltage VNO VIN=-10V BW=10Hz to 100KHz Average Temperature Cofficient of Output Voltage ΔVo / ΔT VIN=-10V Io=5mA f=120Hz 54 60 - dB Io=0.5A - 125 - μV - -0.4 - mV/℃ REV B Page 1 of 10 ELECTRICAL CHARACTERISTICS PARAMETER (Tj=25℃,C1=0.33μF,Co=0.1μF) TEST CONDITIONS SYMBOL Measurement is to be conducted in pulse testing. MIN. TYP. MAX. UNIT ML7906A / ML7906FA Output Voltage Vo VIN=-11V Io=0.5A -5.75 -6.0 -6.25 V Quiescent Current IQ VIN=-11V Io=0mA - 2.2 5.0 mA ΔVo Io VIN=-11V Io=0.005A to 1.5A - 50 120 mV - 12.5 120 mV f=120Hz 54 60 - dB Io=0.5A - 150 - μV Io=5mA - -0.4 - mV/℃ Load Regulation Line Regulation Ripple Rejection ΔVo Vin VIN=-8 to -25V RR VIN=-11V VIN=-11V Output Noise Voltage VNO Average Temperature ΔVo / ΔT VIN=-11V Cofficient of Output Voltage Io=0.5A Io=0.5A ein=2Vp-p BW=10Hz to 100KHz ML7908A / ML7908FA Output Voltage Vo VIN=-14V Io=0.5A -7.7 -8.0 -8.3 V Quiescent Current IQ VIN=-14V Io=0mA - 2.2 5.0 mA ΔVo Io VIN=-14V Io=0.005A to 1.5A - 60 160 mV - 12.5 160 mV f=120Hz 54 60 - dB Io=0.5A - 200 - μV Io=5mA - -0.7 - mV/℃ Load Regulation Line Regulation Ripple Rejection ΔVo Vin VIN=-10.5 to -25V RR VIN=-14V VIN=-14V Output Noise Voltage VNO Average Temperature ΔVo / ΔT VIN=-14V Cofficient of Output Voltage Io=0.5A Io=0.5A ein=2Vp-p BW=10Hz to 100KHz ML7909A / ML7909FA Output Voltage Vo VIN=-15V Io=0.5A -8.65 -9.0 -9.35 V Quiescent Current IQ VIN=-15V Io=0mA - 2.2 5.0 mA ΔVo Io VIN=-15V Io=0.005A to 1.5A - 60 180 mV - 8 180 mV f=120Hz 54 60 - dB Io=0.5A - 250 - μV Io=5mA - -0.8 - mV/℃ Load Regulation Line Regulation Ripple Rejection ΔVo Vin VIN=-11.5 to -25V RR VIN=-15V VIN=-15V Output Noise Voltage VNO Average Temperature ΔVo / ΔT VIN=-15V Cofficient of Output Voltage Io=0.5A Io=0.5A ein=2Vp-p BW=10Hz to 100KHz ML7912A / ML7912FA Output Voltage Vo VIN=-19V Io=0.5A -11.5 -12.0 -12.5 V Quiescent Current IQ VIN=-19V Io=0mA - 2.7 6.0 mA ΔVo Io VIN=-19V Io=0.005A to 1.5A - 60 240 mV - 5 240 mV f=120Hz 54 60 - dB Io=0.5A - 300 - μV - -0.8 - mV/℃ Load Regulation Line Regulation Ripple Rejection ΔVo Vin VIN=-14.5 to -30V RR VIN=-19V VIN=-19V Output Noise Voltage VNO Average Temperature ΔVo / ΔT VIN=-19V Cofficient of Output Voltage Io=0.5A Io=0.5A ein=2Vp-p BW=10Hz to 100KHz Io=5mA REV B Page 2 of 10 ELECTRICAL CHARACTERISTICS PARAMETER (Tj=25℃,C1=0.33μF,Co=0.1μF) TEST CONDITIONS SYMBOL Measurement is to be conducted in pulse testing. MIN. TYP. MAX. UNIT ML7915A / ML7915FA Output Voltage Vo VIN=-23V Io=0.5A -14.4 -15.0 -15.6 V Quiescent Current IQ VIN=-23V Io=0mA - 2.7 6.0 mA ΔVo Io VIN=-23V Io=0.005A to 1.5A - 60 300 mV - 5 300 mV f=120Hz 54 60 - dB Io=0.5A - 375 - μV Io=5mA - -1 - mV/℃ Load Regulation Line Regulation Ripple Rejection ΔVo Vin VIN=-17.5 to -30V RR VIN=-23V VIN=-23V Output Noise Voltage VNO Average Temperature ΔVo / ΔT VIN=-23V Cofficient of Output Voltage Io=0.5A Io=0.5A ein=2Vp-p BW=10Hz to 100KHz ML7918A / ML7918FA Output Voltage Vo VIN=-27V Io=0.5A -17.3 -18.0 -18.7 V Quiescent Current IQ VIN=-27V Io=0mA - 2.7 6.0 mA ΔVo Io VIN=-27V Io=0.005A to 1.5A - 60 360 mV - 5 360 mV f=120Hz 54 60 - dB Io=0.5A - 450 - μV Io=5mA - -1 - mV/℃ -23.0 -24.0 -25.0 V Load Regulation Line Regulation Ripple Rejection ΔVo Vin VIN=-21 to -33V RR VIN=-27V VIN=-27V Output Noise Voltage VNO Average Temperature ΔVo / ΔT VIN=-27V Cofficient of Output Voltage Io=0.5A Io=0.5A ein=2Vp-p BW=10Hz to 100KHz ML7924A / ML7924FA Output Voltage Quiescent Current Load Regulation Line Regulation Ripple Rejection Vo VIN=-33V Io=0.5A IQ VIN=-33V Io=0mA - 2.7 6.0 mA ΔVo Io VIN=-33V Io=0.005A to 1.5A - 85 480 mV - 5 480 mV f=120Hz 54 60 - dB Io=0.5A - 600 - μV - -1 - mV/℃ ΔVo Vin VIN=-28 to -38V RR VIN=-33V VIN=-33V Output Noise Voltage VNO Average Temperature ΔVo / ΔT VIN=-33V Cofficient of Output Voltage Io=0.5A Io=0.5A ein=2Vp-p BW=10Hz to 100KHz Io=5mA REV B Page 3 of 10 ■ Equivalent Circuit ■ Power Dissipation vs. Ambient Temperature HS Power Dissipation PD (W) 20 15 10 5 = Heat Sink Thermal Resistance Heat Sink HS = 3 C/W HS = 5 C/W HS = 10 C/W HS = 20 C/W Without Heat Sink 0 25 50 75 Ambient Temperature Ta ( C) ■ Test Circuit 1. Output Voltage, Line Regulation, Load Regulation, Quiescent Current, Average Temperature Coefficient of Output Voltage, Output Noise Voltage. 2 1 3 2. Ripple Rejection 1 2 3 REV B Page 4 of 10 ■ Typical Characteristics REV B Page 5 of 10 ■ Typical Characteristics REV B Page 6 of 10 1. Application Circuit In the following explain only the positive regulator unless otherwise specified. However they can apply to the negative voltage regulator by easy change. Positive/Negative Voltage Supply Note : In the above positive and negative power supply application, D1 and D2 should be connected. If D1 and D2 are not connected, either of positive or negative power supply circuit may not turns on. 78 series IN +Vin OUT +Vo GND 0.33uF D1 0.1uF D2 0.1uF COM 0.33uF COM IN -Vin OUT -Vo 79 series 2. Note in Application Circuit If the higher voltage (above the rated value) or lower voltage (GND-0.5V) is supplied to the input terminals, the IC may be destroyed. To avoid such a case, a zener diode or other parts of the surge supressor should be connected as shown below. (1) L R 1 OUT 3 Vo 1 Vin + Capacitor Diode Capacitor OUT 3 Vo 2 (2) + 2 Ze ner Diode IN GND IN GND Vin If the higher voltage than the input terminal is supplied to the output terminal, the IC may be destroyed. To avoid input terminal short to the GND or the stored voltage in the capacitor back to the output terminal, by the large value capacitor connecting to the output terminal application, the SBD should be required as shown below; DIODE 1 IN GND Vin OUT 3 Vo + Capacitor 2 * In case of negative voltage regulator, reverse the SBD and capacitor direction. REV B Page 7 of 10 3. Thermal Design (1) Heat Producting There are two kinds of heat producting (P LOSS-1, PLOSS-2) in three terminal regulator and the sum of them is total heat producting of IC (PLOSS). (1-1) PLOSS-1 : heat producting by own operation Input voltage (Vin) and quiescent current (IQ) produce the heat mentioned below equation. PLOSS-1 = Vin X IQ Input IN OUT Iout Output GND Vin Vout IQ (1-2) PLOSS-2 : heat producing by output current and the input-output differential voltage. Internal power transistor produces the hest mentioned following equation. PLOSS-2 = (Vin-Vout) x Iout (W) Therefore, the total heat producing PLOSS is : PLOSS = PLOSS-1 + PLOSS-2 = Vin X IQ + (Vin-Vout) X Iout (2) Thermal Resistance (2-1) Definition of Thermal Resistance : θ (W) Thermal resistance (θ ) is a degree of heat radiation mentioned following equation. = (T1 - T2)/P (℃ /W) Heat Producing Quantity Ambient Temperature or case temperature Heat Source Temperature : P (W) :T2 (℃ ) :T1 (℃ ) P(W) T1 Rp T2 T1 > T2 (2-2) Thermal resistance of TO-220 There are two kinds of thermal resistance of TO-220. One is "θjc" for the application with the heat sink, the other is "θja" for the application without the heat sink. thermal resistance between IC chip (junction point) and the package back side θjc : contacting with the heat sink. θja : thermal resistance between IC chip (junction point) and ambience. REV B Page 8 of 10 (3) Heat Radiation Balance The heat produced in the IC is radiated to ambience through the package and the heat sink. The quantity of the heat radiation depends on the heat source temperature, ambient temperature and the thermal resistance of the package. (3-1) TO-220 with heat sink Heat radiation balance model of the TO-220 with heat sink is shown as below. PLOSS θJC θCH θJS Tj Ta Ambient Temperature Heat Source (junction) Temperature Where θHS θjc : thermal resistance between IC chip (junction point) and the package backside connecting to the heatsink. θjs : thermal resistance between IC chip (junction point) and the package surface. θCH : thermal resistance between package backside and the heat sink including the condidtion of insulator, silicon grease and tighten torque. θHS : thermal resistance of the heat sink Package Face Side Resin θJS Chip Package Back Side IC θJC θCH θHS Heat Sink If the js is large enough compare with other thermal resistance, the js can be neglected and the heat radiation model can be mentioned as below. PLOSS θJC θCH θHS Tj Ta The relation between temperature and heat radiation quantity is shown below. Tj=P LOSS X (θjc+θCH +θHS) + Ta REV B (℃ ) Page 9 of 10 (4) Thermal Design The heat radiation balance model of the TO-220 with the heat sink is shown as follows. Heat radiation balance Tj = P LOSS X (θjc +θCH + θHS) + Ta (℃ ) (4-1) PLOSS = Vin X IQ + (Vin-Vout) X Iout (W) (4-2) (℃) (4-3) Substituting "Eq.(4-2) into "Eq.(4-1)" obtains Tj = [Vin X I Q +(Vin-Vout) X Iout] X (θjc +θCH +θHS)+Ta In Eq.(4-3) Vin, Iout, θCH, θHS, Ta depand on using condition. Tj, I Q,Vout,θjc depend on IC depend on IC specification. WhenθCH, IQ and Tj are assumed the following values, Eq.(4-3) becomes Eq.(4-4). θCH=0.3 to 0.4 (℃/W) Insert the mica paper (0.1t) and thermal conduction silicon grease between the IC and heat sink and tighten them with the bolt by 4Kg*cm-min. IQ = 5 to 6mA (max.) Tj = 125℃ (max.) Tj(max) = 125 = [5 X Vin + (Vin-Vout) X Iout] X (5+0.3+ θHS) +Ta (℃) (4-4) When fix the Vout, Tj depends on the Vin, Iout, θHS and Ta. It means; Lower Vin and / or Iout are required to linit the temperature rise. Smaller θHS is required for the effective heat reduce (i.e. using the large heat sink). In the thermal design, when fix the Vin, Iout and Ta, selectthe heat sink which θHS is smaller that the result of Eq.(4-4). For more detail, please refer the heat resistance value mentioned in the specification of the heat sink supplier. REV B Page 10 of 10