LM4041DIM3-ADJ TR Micrel Inc, LM4041DIM3-ADJ TR Datasheet - Page 13

• Manufacturer Part Number: LM4041DIM3-ADJ TR
• Description: IC REF ADJ 0.5% 150PPM SOT-23
• Manufacturer: Micrel Inc

Specifications of LM4041DIM3-ADJ TR

• Reference Type: Shunt
• Voltage - Output: 1.24 ~ 10 V
• Tolerance: ±1%
• Temperature Coefficient: 150ppm/°C
• Number Of Channels: 1
• Current - Cathode: 65µA
• Current - Output: 12mA
• Operating Temperature: -40°C ~ 85°C
• Mounting Type: Surface Mount
• Package / Case: SOT-23-3, TO-236-3, Micro3™, SSD3, SST3
• Lead Free Status / RoHS Status: Contains lead / RoHS non-compliant
• Voltage - Input: -
• Current - Quiescent: -
• Other names: LM4041DIM3-ADJMLTR; LM4041DIM3-ADJMLTR

Applications Information
The stable operation of the LM4040 and LM4041 references
requires an external capacitor greater than 10nF connected
between the (+) and (–) pins. Bypass capacitors with values
between 100pF and 10nF have been found to cause the
devices to exhibit instabilities.
Schottky Diode
LM4040-x.x and LM4041-1.2 in the SOT-23 package have
a parasitic Schottky diode between pin 2 (–) and pin 3 (die
attach interface connect). Pin 3 of the SOT-23 package must
float or be connected to pin 2. LM4041-ADJs use pin 3 as
the (–) output.
Conventional Shunt Regulator
In a conventional shunt regulator application (see Figure 1),
an external series resistor (R
supply voltage and the LM4040-x.x or LM4041-1.2 reference.
R
and the reference (I
age may vary, R
the minimum acceptable I
supply voltage is at its minimum and the load current is at
its maximum value. When the supply voltage is at its maxi-
mum and I
that the current flowing through the LM4040-x.x is less than
15mA, and the current flowing through the LM4041-1.2 or
LM4041-ADJ is less than 12mA.
R
operating current, (I
breakdown voltage (V
Typical Application Circuits
March 2005
S
S
is determined by the supply voltage (V
determines the current that flows through the load (I
L
is at its minimum, R
Figure 3. Voltage Level Detector
LM4041-ADJ
S
R
should be small enough to supply at least
s
= (V
Q
L
). Since load current and supply volt-
and I
R
):
s
– V
Q
D1
Q
to the reference even when the
), and the reference’s reverse
R
–5V
S
) / (I
) is connected between the
S
+
R3
200
–
should be large enough so
λ
L
FB
+ I
< –12V
LED ON
Q
)
R1
120k
R2
1M
S
), the load and
L
)
13
Adjustable Regulator
The LM4041-ADJ’s output voltage can be adjusted to any
value in the range of 1.24V through 10V. It is a function of
the internal reference voltage (V
ternal feedback resistors as shown in Figure 2. The output
is found using the equation:
(1)
where V
the internal V
is determined by:
(2)
where V
in the “Electrical Characteristics” and is typically –1.3mV/V and
V
(1) with the value V
Note that actual output voltage can deviate from that pre-
dicted using the typical ΔV
grade parts, the worst-case ΔV
V
The following example shows the difference in output volt-
age resulting from the typical and worst case values of
ΔV
Let V
is 1.223V. Choosing a value of R1 = 10kΩ, R2 = 63.272kΩ.
Using the worst case ΔV
grade parts, the output voltage is actually 8.965V and 8.946V
respectively. This results in possible errors as large as
0.39% for the C-grade parts and 0.59% for the D-grade parts.
Once again, resistor values found using the typical value of
ΔV
adjustment.
Y
Y
is equal to 1.233V. Replace the value of V
REF
REF
= 1.248V.
O
= +9V. Using the typical values of ΔV
/ ΔV
/ ΔV
O
O
is the desired output voltage. ΔV
is the desired output voltage. The actual value of
O
O
Figure 4. Voltage Level Detector
.
REF
will work in most cases, requiring no further
V
V
D1
is a function of V
O
REF
REF
= V
´ = V
λ
LM4041-
REF
found using equation (2).
REF
ADJ
O
REF
[ (R2/R1) + 1 ]
(ΔV
–5V
/ ΔV
/ ΔV
+
REF
–
R3
330
REF
REF
FB
O
O
O
) and the ratio of the ex-
. The “corrected” V
/ ΔV
for the C-grade and D-
> –12V
LED ON
/ ΔV
in equation (2); for C-
R1
120k
R2
1M
O
O
REF
) + V
is –2.5mV/V and
REF
REF
/ ΔV
Y
M9999-031805
/ΔV
in equation
O
O
is found
, V
REF
REF