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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)
1. OUT 2. IN 3. COMMON
32
TO-220F (7900FA)
1
ABSOLUTE MAXIMUM RATINGS
PARAMETER
Input Voltage
(Ta=25)
SYMBOL
VIN
Maximum Rating
ML7905 to ML7909 ML7912 to ML7920 ML7924 -35 -35 -40 -40 to +125 Operating Junction Temperature Operating Ambient Temperature Tj Topr 15(Tc45 ) -30 to +125 -30 to +75
UNIT
V
Storage Temperature Range Operating Temperature Range Power Dissipation
Tstg
W
PD
THERMAL RESISTANCE
Thermal Resistance Junction-to-Ambient Temperature Junction-to-Case ja jc 60 5 /W
ELECTRICAL CHARACTERISTICS
PARAMETER
ML7905A / ML7905FA Output Voltage Quiescent Current Load Regulation Line Regulation Ripple Rejection Output Noise Voltage Average Temperature Cofficient of Output Voltage Vo IQ Vo Io Vo Vin RR VNO VIN=-10V VIN=-10V VIN=-10V
(Tj=25,C1=0.33F,Co=0.1F)
Measurement is to be conducted in pulse testing.
SYMBOL
TEST CONDITIONS
MIN. TYP. MAX. UNIT
Io=0.5A Io=0mA Io=0.005A to 1.5A
-4.8 -
-5.0 2.2 50 12.5 60 125 -0.4
-5.2 5.0 100 100 -
V mA mV mV dB V mV/
VIN=-7 to -25V Io=0.5A VIN=-10V VIN=-10V Io=0.5A
ein=2Vp-p
f=120Hz Io=0.5A
54 -
BW=10Hz to 100KHz Io=5mA
Vo / T VIN=-10V
REV B
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ELECTRICAL CHARACTERISTICS
PARAMETER
ML7906A / ML7906FA Output Voltage Quiescent Current Load Regulation Line Regulation Ripple Rejection Vo IQ Vo Io VIN=-11V VIN=-11V VIN=-11V
(Tj=25,C1=0.33F,Co=0.1F)
Measurement is to be conducted in pulse testing.
SYMBOL
TEST CONDITIONS
MIN. TYP. MAX. UNIT
Io=0.5A Io=0mA Io=0.005A to 1.5A Io=0.5A Io=0.5A
-5.75 f=120Hz Io=0.5A 54 -
-6.0 2.2 50 12.5 60 150 -0.4
-6.25 5.0 120 120 -
V mA mV mV dB V mV/
Vo Vin VIN=-8 to -25V RR VIN=-11V
ein=2Vp-p
VIN=-11V Output Noise Voltage VNO Average Temperature Vo / T VIN=-11V Cofficient of Output Voltage ML7908A / ML7908FA Output Voltage Quiescent Current Load Regulation Line Regulation Ripple Rejection Vo IQ Vo Io VIN=-14V VIN=-14V VIN=-14V
BW=10Hz to 100KHz Io=5mA
Io=0.5A Io=0mA Io=0.005A to 1.5A Io=0.5A
-7.7 f=120Hz Io=0.5A 54 -
-8.0 2.2 60 12.5 60 200 -0.7
-8.3 5.0 160 160 -
V mA mV mV dB V mV/
Vo Vin VIN=-10.5 to -25V RR VIN=-14V Io=0.5A
ein=2Vp-p
VIN=-14V Output Noise Voltage VNO Average Temperature Vo / T VIN=-14V Cofficient of Output Voltage ML7909A / ML7909FA Output Voltage Quiescent Current Load Regulation Line Regulation Ripple Rejection Vo IQ Vo Io VIN=-15V VIN=-15V VIN=-15V
BW=10Hz to 100KHz Io=5mA
Io=0.5A Io=0mA Io=0.005A to 1.5A Io=0.5A
-8.65 f=120Hz Io=0.5A 54 -
-9.0 2.2 60 8 60 250 -0.8
-9.35 5.0 180 180 -
V mA mV mV dB V mV/
Vo Vin VIN=-11.5 to -25V RR VIN=-15V Io=0.5A
ein=2Vp-p
VIN=-15V Output Noise Voltage VNO Average Temperature Vo / T VIN=-15V Cofficient of Output Voltage ML7912A / ML7912FA Output Voltage Quiescent Current Load Regulation Line Regulation Ripple Rejection Vo IQ Vo Io VIN=-19V VIN=-19V VIN=-19V
BW=10Hz to 100KHz Io=5mA
Io=0.5A Io=0mA Io=0.005A to 1.5A Io=0.5A
-11.5 f=120Hz Io=0.5A 54 -
-12.0 2.7 60 5 60 300 -0.8
-12.5 6.0 240 240 -
V mA mV mV dB V mV/
Vo Vin VIN=-14.5 to -30V RR VIN=-19V Io=0.5A
ein=2Vp-p
VIN=-19V Output Noise Voltage VNO Average Temperature Vo / T VIN=-19V Cofficient of Output Voltage
BW=10Hz to 100KHz Io=5mA
REV B
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ELECTRICAL CHARACTERISTICS
PARAMETER
ML7915A / ML7915FA Output Voltage Quiescent Current Load Regulation Line Regulation Ripple Rejection Vo IQ Vo Io VIN=-23V VIN=-23V VIN=-23V
(Tj=25,C1=0.33F,Co=0.1F)
Measurement is to be conducted in pulse testing.
SYMBOL
TEST CONDITIONS
MIN. TYP. MAX. UNIT
Io=0.5A Io=0mA Io=0.005A to 1.5A Io=0.5A
-14.4 f=120Hz Io=0.5A 54 -
-15.0 2.7 60 5 60 375 -1
-15.6 6.0 300 300 -
V mA mV mV dB V mV/
Vo Vin VIN=-17.5 to -30V RR VIN=-23V Io=0.5A
ein=2Vp-p
VIN=-23V Output Noise Voltage VNO Average Temperature Vo / T VIN=-23V Cofficient of Output Voltage ML7918A / ML7918FA Output Voltage Quiescent Current Load Regulation Line Regulation Ripple Rejection Vo IQ Vo Io VIN=-27V VIN=-27V VIN=-27V
BW=10Hz to 100KHz Io=5mA
Io=0.5A Io=0mA Io=0.005A to 1.5A Io=0.5A
-17.3 f=120Hz Io=0.5A 54 -
-18.0 2.7 60 5 60 450 -1
-18.7 6.0 360 360 -
V mA mV mV dB V mV/
Vo Vin VIN=-21 to -33V RR VIN=-27V Io=0.5A
ein=2Vp-p
VIN=-27V Output Noise Voltage VNO Average Temperature Vo / T VIN=-27V Cofficient of Output Voltage ML7924A / ML7924FA Output Voltage Quiescent Current Load Regulation Line Regulation Ripple Rejection Vo IQ Vo Io VIN=-33V VIN=-33V VIN=-33V
BW=10Hz to 100KHz Io=5mA
Io=0.5A Io=0mA Io=0.005A to 1.5A Io=0.5A
-23.0 f=120Hz Io=0.5A 54 -
-24.0 2.7 85 5 60 600 -1
-25.0 6.0 480 480 -
V mA mV mV dB V mV/
Vo Vin VIN=-28 to -38V RR VIN=-33V Io=0.5A
ein=2Vp-p
VIN=-33V Output Noise Voltage VNO Average Temperature Vo / T VIN=-33V Cofficient of Output Voltage
BW=10Hz to 100KHz Io=5mA
REV B
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Equivalent Circuit
Power Dissipation vs. Ambient Temperature
HS
20
Power Dissipation PD (W)
Heat Sink
= Heat Sink Thermal Resistance
15
HS
= 3 C/W = 5 C/W
10
HS
HS
= 10 C/W = 20 C/W
5
HS
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. Ripple Rejection
2 3
1
2 3
1
REV B
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Typical Characteristics
REV B
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Typical Characteristics
REV B
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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
78 series +Vin IN GND 0.33uF D1 0.1uF OUT +Vo
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.
COM
0.33uF COM -Vin IN 79 series OUT
D2
0.1uF
-Vo
2. Note in Application Circuit
(1) 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.
L
R Vin
1
IN
OUT
3
Vo
Vin
1
IN
OUT
3
Vo
GND
GND
+
Ze ner Diode
Capacitor
+
Diode Capacitor
(2)
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
2
2
Vin
1
IN
OUT
3
Vo
* In case of negative voltage regulator, reverse the SBD and capacitor direction.
GND 2
+
Capacitor
REV B
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3. Thermal Design
(1) Heat Producting There are two kinds of heat producting (PLOSS-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
Vin
IN GND
OUT
Iout
Output
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) (2-1) Thermal Resistance Definition of Thermal Resistance : Thermal resistance ( ) 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)
(W)
: P (W) :T2 ( ) :T1 ( )
T1
Rp T1 > T2
T2
(2-2)
Thermal resistance of TO-220 There are two kinds of thermal resistance of TO-220. One is "jc" for the application with the heat sink, the other is "ja" for the application without the heat sink. thermal resistance between IC chip (junction point) and the package back side jc : contacting with the heat sink.
ja :
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
JC
CH
HS
Tj
Heat Source (junction) Temperature
JS
Ambient Temperature
Ta
Where
jc : js : CH :
thermal resistance between IC chip (junction point) and the package backside connecting to the heatsink. thermal resistance between IC chip (junction point) and the package surface. thermal resistance between package backside and the heat sink including the condidtion of insulator, silicon grease and tighten torque. thermal resistance of the heat sink
Package Face Side Resin Chip Package Back Side
HS :
JS JC CH HS
IC
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
JC
CH
HS
Tj
Ta
The relation between temperature and heat radiation quantity is shown below. Tj=PLOSS X (jc+CH +HS) + Ta ( )
REV B
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(4)
Thermal Design
The heat radiation balance model of the TO-220 with the heat sink is shown as follows. Heat radiation balance Tj = PLOSS X (jc +CH + HS) + Ta PLOSS = Vin X IQ + (Vin-Vout) X Iout Substituting "Eq.(4-2) into "Eq.(4-1)" obtains Tj = [Vin X IQ +(Vin-Vout) X Iout] X (jc +CH +HS)+Ta In Eq.(4-3) Vin, Iout, CH, HS, Ta depand on using condition. Tj, IQ,Vout,jc depend on IC depend on IC specification. WhenCH, IQ and Tj are assumed the following values, Eq.(4-3) becomes Eq.(4-4). CH=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+ HS) +Ta When fix the Vout, Tj depends on the Vin, Iout, HS and Ta. It means; Lower Vin and / or Iout are required to linit the temperature rise. Smaller HS 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 HS 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. () (4-4) () (4-3) ( ) (W) (4-1) (4-2)
REV B
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