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DISCRETE SEMICONDUCTORS
DATA SH EET
, halfpage
MBD127
PSSI2021SAY
Constant current source
Product specification 2001 May 07
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Philips Semiconductors Product specification
Constant current source PSSI2021SAY
FEATURES
• One chip constant current source
• Reduced number of components and board space.
APPLICATIONS
• Especially suitable for space reduction in, for example,
LED driving circuits or active bias controlling.
DESCRIPTION
Resistor equipped PNP transistor with two diodes on one
chipinaplastic SC-88Apackage. Built-inbias resistorand
two diodes allow operation as constant current source.
The stabilized current canbe adjustedbetween 15 µAand
50 mA by connection of external resistors between
pins 4 and 5.
MARKING
TYPE NUMBER MARKING CODE
PSSI2021SAY S1p
PINNING
PIN SYMBOL DESCRIPTION
1 n.c. not connected
2I
stab/Vout
stabilized current/output voltage
3 GND ground
4R
5V
handbook, halfpage
5
1
Top view
external
S
2
external resistor
supply voltage
4
3
54
n.c.
Fig.1 Simplified outline (SC-88A) and symbol.
321
MGU348
LIMITING VALUES
In accordance with the Absolute Maximum Rating System (IEC 60134).
SYMBOL PARAMETER CONDITIONS MIN. MAX. UNIT
V
V
V
I
stab
P
T
T
T
S
out
R
tot
stg
j
amb
supply voltage − 75 V
output voltage VS=75V − 73 V
reverse voltage between all terminals − 0.5 V
continuous stabilized current (DC) − 50 mA
total power dissipation T
≤ 25 °C; note 1 − 335 mW
amb
storage temperature −65 +150 °C
junction temperature − 150 °C
operating ambient temperature −65 +150 °C
Note
1. Device mounted on a FR4 printed-circuit board.
2001 May 07 2
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Philips Semiconductors Product specification
Constant current source PSSI2021SAY
THERMAL CHARACTERISTICS
SYMBOL PARAMETER CONDITIONS VALUE UNIT
R
th j-a
Note
1. Device mounted on a FR4 printed-circuit board.
CHARACTERISTICS
T
=25°C unless otherwise specified.
amb
SYMBOL PARAMETER CONDITIONS MIN. TYP. MAX. UNIT
I
stab
I
supply
∆I
stab
--------------I
stab
∆ I
stab
-------------------------
∆TI
×
thermal resistance from junction to
ambient
stabilized current VS= 12 V; V
supply current VS= 12 V; V
stability of stabilized current as
a function of V
control
stability of stabilized current as
stab
a function of temperature
in free air; note 1 370 K/W
= 0 to 10 V;
out
R
I
stab
V
I
stab
V
T
V
T
= infinity
external
= 0 to 10 V;
out
=15µA
= 75 V; V
S
out
=0V;
=15µA
= 1 to 10 V; VS=12V;
out
=25°C
amb
=1V; VS=12V;
out
= −55 to +150 °C
amb
10 15 20 µA
− 240 370 µA
− 1.5 2.2 mA
− 0.5 1 %
− 0.15 0.3 %
2001 May 07 3