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Details, datasheet, quote on part number:ZH431F02TA
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Datasheet text preview:
ADJUSTABLE PRECISION ZENER SHUNT REGULATOR
Issue 2 - February 1998 DEVICE DESCRIPTION
The ZH431 is a three terminal adjustable shunt regulator offering excellent temperature stability and output current handling capability up to 30mA. The output voltage may be set to any chosen voltage between 2.5 and 36 volts by selection of two external divider resistors. The devices can be used as a replacement f o r zener diodes in many applications requi ring an i mprovement in zener performance.They are also ideal for use in the feedback circuits of off line SMPUs as well as many general purpose regulator and reference applications where initial accuracy and low temperature coefficient are key requirements. Note: ZH431 is not recommended for new designs. Refer to ZR431
ZH431
F EATURES
· · · · · · · · · · · · ·
Surface mount SO8, SOT223,SOT23 and SOT89 packages TO92 package 2% and 1% tolerance Maximum temperature coefficient 55 ppm/°C Temperature compensated for operation over the full temperature range Programmable output voltage 50µA to 30mA current sink capability Low output noise
APPLICATIONS
Shunt regulator Series regulator Voltage monitor Over voltage/ under voltage protection Switch mode power supplies
SCHEMATIC DIAGRAM
VZ V ref
Gnd
4-15
ZH431
ABSOLUTE MAXIMUM RATING
Cathode Voltage (VZ) 40V Cathode Current 50mA Operating Temperature -40 to 85°C Storage Temperature -55 to 125°C Recommended Operating Conditions Min Max Cathode Voltage Vref 36V Cathode Current 50µA 30mA Power Dissipation (Tamb=25°C, Tjmax=150°C) SOT23 330mW TO92 780mW SOT223 2W SO8 780mW SOT89 1.5W
ELECTRICAL CHARACTERISTICS TEST CONDITIONS (Unless otherwise stated):Tamb=25°C
PARAMETER Reference Voltage Deviation of Reference Input Voltage over Temperature Ratio of the change in Reference Voltage to the Change in Cathode Voltage Reference Input Current Deviation of Reference Input Current over Temperature Minimum Cathode Current for Regulation
SYMBOL
VALUE MIN TYP MAX UNITS CONDITIONS IL=10mA (Fig1), VZ=Vref IL=10mA, VZ=Vref Ta=full range (Fig1) VZ from Vref to 10V IZ=10mA (Fig2) VZ from 10V to 36V IZ=10mA (Fig2) R1=10k, R2=O/C, lL=10mA (Fig2) R1=10k, R2=O/C, IL=10mA Ta=full range (Fig2) VZ=Vref (Fig1) VZ=Vref (Fig1), f=0Hz 2.45 2.50 2.55 V 2.475 2.50 2.525 8.0 17 mV
2% Vref 1% Vdev
Vref VZ
-0.7 -0.6
-2.7 -2.0
mV/V mV/V µA µA
Iref Iref
0.15 1.0 0.06 0.2
IZmin
21
50 0.75
µA
Dynamic Output Impedance RZ
Deviation of reference input voltage, Vdev, is defined as the maximum variation of the reference input voltage over the full temperature range. The average temperature coefficient of the reference input voltage, Vref is defined as:
Vmax
Vmin
Vdev = Vmax - Vmin
Vdev x 1000000 Vref (T1-T2) The dynamic output impedance, Rz, is defined as: VZ RZ = IZ When the device is programmed with two external resistors, R1 and R2, (fig 2) , the dynamic output impedance of the overall circuit, R', is defined as: R1 R'=Rz (1+ ) R2 Vref (ppm / °C)=
T2
T1
Temperature
4-16
ZH431
TYPICAL CHARACTERISTICS
200
Vref= Vz Iz= 10mA
5
Change in Reference Voltage (mV)
Reference Current (nA)
180 160 140
0 -5 -10 -15 -20 -25 0 5 10 15 20 25 30 35 40
120 100 -40
-20
0
20
40
60
80
Temperature (°C)
Cathode Voltage (V)
Reference Current v Temperature
26
Vref= Vz
Change in Vref v Cathode Voltage
100
1mA
Minimum Cathode Current (uA)
24 22 20 18 16 14 12 -40
Dynamic Impedance (Ohms)
10
Vref=Vz
10mA
1
0.1
-20
0
20
40
60
80
0.01 100
1k
10k
100k
1M
Temperature (°C)
Frequency (Hz)
Cathode Current v Temperature
2.52
Iz= 10mA
Dynamic Impedance v Frequency
2.0
2.51
Reference Voltage (V)
Power Dissipation (W)
SOT223
2.50 2.49
1.0
SOT89 S08/T092 SOT23
2.48 2.47 -40
-20
0
20
40
60
80
0 25
50
75
100
Temperature (°C)
Ambient Temperature (°C)
Reference Voltage v Temperature
Power Dissipation Derating
4-17
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