TL431−Q1

ADJUSTABLE PRECISION SHUNT REGULATOR

SGLS302D − MARCH 2005 − REVISED MARCH 2013

4

POST OFFICE BOX 655303

noted)

PARAMETER

TEST

TEST CONDITIONS

TL431BQ

UNIT

PARAMETER

TEST

CIRCUIT

TEST CONDITIONS

MIN

TYP

MAX

UNIT

Reference voltage

2

2483

2495

2507

mV

Deviation of reference voltage

over full temperature range

(see Figure 1)

2

14

34

mV

Ratio of change in reference voltage

3

I

10 mA

−1.4

−2.7

mV

Ratio of change in reference voltage

to the change in cathode voltage

3

−1

−2

mV

V

Reference current

3

2

4

μA

Deviation of reference current

over full temperature range

(see Figure 1)

3

0.8

2.5

μA

Minimum cathode current

for regulation

2

0.4

0.7

mA

Off-state cathode current

4

0.1

0.5

μA

Dynamic impedance (see Figure 1)

1

f ≤ 1 kHz

0.2

0.5

Ω

values obtained over the recommended temperature range. The average full-range temperature coefficient of the

where:

lower temperature.

Calculating Dynamic Impedance

The dynamic impedance is defined as:

When the device is operating with two external resistors (see Figure 3), the total dynamic impedance of the circuit

is given by:

ref

ppm

°C +

VI(dev)

Vref at 25°C

4mV

2495 mV

70°C

[

23 ppm

°C

|z

|z | + DV

DI [

|z

1 ) R1

R2

ref

Figure 1. Calculating Deviation Parameters and Dynamic Impedance