MAX6125 Maxim, MAX6125 Datasheet - Page 7

• Manufacturer Part Number: MAX6125
• Description: SOT23 / Low-Cost / Low-Dropout / 3-Terminal Voltage References
• Manufacturer: Maxim

Set the output voltage on the MAX6160 by connecting
a resistor divider between OUT, ADJ, and GND
(Figure 1). Choose R1 according to the following equa-
tion:
where V
compensates for the MAX6160's change in ADJ input
current over temperature. When R1 is chosen correctly,
the change in voltage across R1 caused by the ADJ
input current is properly cancelled. Choose R1 to within
* Except MAX6160.
** MAX6160 only.
Figure 1. MAX6160 Adjustable Output Circuit
______________________________________________________________Pin Description
_____________Applications Information
2, 3, 5*, 6, 7
Setting the MAX6160 Output Voltage
SO
5**
TH
1
4
8
MAX6160
R1 = (1.06 x 10
GND
= 1.23V. The scaling factor (1.06 x 10
V
IN
IN
OUT
ADJ
_______________________________________________________________________________________
PIN
SOT23-3
5
—
—
R1
2
3
1
R2
) (V
V
OUT
OUT
R1 = 1.06 x 10
R2 = –—––––
V
ADJ
/ V
(
–––– - 1
= 1.23V
V
V
SOT143
OUT
ADJ
ADJ
R1
SOT23, Low-Cost, Low-Dropout,
—
4
1
2
3
)(kΩ)
5
)
3-Terminal Voltage References
(
––––
V
V
OUT
ADJ
)
( k )
NAME
GND
OUT
N.C.
ADJ
IN
5
)
Reference Output
No Connection. Not internally connected.
Ground
Adjustable output voltage feedback input. Connect a resistor
divider between OUT, ADJ, and GND (Figure 1).
Input Voltage
±5% of this calculated value (nearest standard value
plus specified resistor tolerance) to optimize the output
voltage temperature coefficient. Using R1 = 215kΩ:
which is also the nearest 0.1% resistor value.
Choose R2 according to the following equation:
For example, a 2.5V output requires R1 = (1.06 x 10
(2.5V / 1.23V) ≈ 215Ω, which is the nearest standard-
value 0.1% resistor.
For the best line-transient performance, decouple the
input with a 0.1µF ceramic capacitor, as shown in the
Typical Operating Circuit . Locate the capacitor as
close to the device pin as possible. Where transient
performance is less important, no capacitor is
necessary.
The MAX6125/MAX6141/MAX6145/MAX6150/MAX6160
do not require an output capacitor. They are stable for
capacitive loads from 0nF to 10nF. If your application
requires an output charge reservoir (e.g., to decouple
the reference from a DAC’s input), then make sure that
the total output capacitive load does not exceed 10nF
for optimum settling-time performance.
R2 = R1 / (V
R2 = 215k
FUNCTION
OUT
1.23V
2.5V
/ V
ADJ
- 1
Output Bypassing
- 1)
Input Bypassing
208k ,
5
7
)