SPX4040 Sipexoration, SPX4040 Datasheet - Page 4

• Manufacturer Part Number: SPX4040
• Description: Precision Micropower 2.5V Shunt Voltage Reference
• Manufacturer: Sipexoration

SPX4040 Applications Hints
This device is designed for stable operation and has no need
of an external capacitor between pin 4 and 8. The reference
remains stable if a bypass capacitor is used.
SOT-23
The SPX4040 in the SOT-23 package has a parasitic
Schottky diode between pin 3 and pin 1. Pin 1 of SOT-23
must float or be connected to pin 3.
Conventional Shunt Regulator
In a conventional shunt regulator application (see Figure 1),
an external series resister (R
supply voltage and the SPX4040. R
that flows through the load (I
load current and supply voltage may vary, R
enough to supply at least the minimum acceptable I
reference even when the supply voltage is at its minimum and
the load current is at its maximum value. When the supply
voltage is at its maximum and I
be large enough so that the current flowing through the
SPX4040 is less than 15mA
R
operating current (I
voltage (V
S
is determined by the supply voltage (V
R
).
R
S
L
= (V
and I
S
Q
), reference’s reverse breakdown
- V
L
) and the reference(I
S
L
) is connected between the
R
is at its minimum, R
)/(I
S
L
determines the current
+I
Q
)
S
S
should be small
), the load and
Q
). Since
S
Q
should
to the
Shunt Regulator Application
Figure 1. SPX4040 Fixed
SPX4040
R
V
R
S
V
S
I
O
I
+ I
Q
L
I
L
SPX4040
Rev. 10/25/00
V
O