MX584 Просмотр технического описания (PDF) - Maxim Integrated
Номер в каталоге
Компоненты Описание
производитель
MX584 Datasheet PDF : 10 Pages
| |||
Pin-Programmable, Precision Voltage
Reference
Detailed Description
As shown in Figure 1, most applications of the MX584
require no external components. Connections to +VS
and COMMON (COMMON is also tied to the case in the
TO-99 metal package) with all other pins unconnected
result in a buffered +10.00V output at pin 1. The other
pretrimmed voltages are obtained by strapping pins as
shown in Table 1. If one or more external buffer ampli-
fiers are connected to the programming pins (pins 2, 3),
multiple outputs can be obtained from one reference.
Other Output Voltages
The MX584 can be adjusted to a different output volt-
age by adding one or more resistors as in Figure 2. As
the diagram shows, the reference can be thought of as
a 1.215V bandgap followed by a noninverting amplifier.
If R1 and R2 are used alone, the adjustment range is
widest but the resolution of the trim may be too coarse,
even when a multi-turn trip pot is used.
When adding external resistors, output voltages well
above 10V can be obtained. R2 should therefore be
chosen carefully since it sets the maximum output volt-
age. R2’s resistance should not be so low as to jeopar-
dize other circuits if R1 is misadjusted.
The fixed output voltages can also be varied by con-
necting only one resistor, as in the dashed lines in
Figure 2. Connecting R3 alone raises VOUT while R4
alone lowers it. These resistors (or potentiometers)
must have very low temperature coefficients if accuracy
over temperature is to be unaffected by the adjustment.
If fine adjustment of the output is all that is required, the
circuit of Figure 3 is recommended. It provides good
stability and resolution for a trim range of ±200mV. If
the 2.5V output is adjusted, R2 should be connected to
VBG, pin 6, and the trim range should be limited to
±100mV.
Voltage Temperature Coefficient
The temperature characteristic of the MX584 consis-
tently follows an "S-curve" as shown in the Typical
Operating Characteristics. A five-point 100% test guar-
antees compliance with -55°C to +125°C specifications
and a three-point 100% test guarantees 0°C to +70°C
specifications.
The tolerance specifications in the Electrical
Characteristics table state the maximum deviation from
the reference’s initial value at +25°C. By adding the
maximum deviation for a given device to its initial toler-
ance, the total possible error is determined.
Table 1. Programming Pin Connections
OUTPUT VOLTAGE
(V)
PROGRAMMING (OUTPUT ON PIN 1)
10
Pins 2 and 3 are unconnected
7.5
Connect pins 2 and 3 together
5.0
Connect pins 2 and 1 together
2.5
Connect pins 3 and 1 together
+(VOUT + 2.5V) TO +30V
8
+VS
1
10.0V
MX584 5.0V 2
3
2.5V
4
VOUT,
+2.5V, +5.0V, +7.5V, +10V
Figure 1. Basic Connection for Positive Outputs
VSUPPLY
8
+VS
MX584 10V 1
VOUT
+1.215V
8kΩ
+2.5V*
4kΩ
5V 2
2.5V 3
VBG 5
4kΩ
COM 4
R4
R1
R3
R2
*THE 2.5V TAP (PIN 3) IS USED INTERNALLY AS A BIAS POINT AND SHOULD
NOT BE CHANGED BY MORE THAN 100mV IN ANY TRIM CONFIGURATION.
Figure 2. Variable Output Options
4 _______________________________________________________________________________________
Share Link: 