Diodes ZR431 - Manual (Page 3)

ZR431
ADJUSTABLE PRECISION ZENER SHUNT REGULATOR
ZR431
Document number: DS33255 Rev. 6 - 2
3 of 9
www.diodes.com
October 2011
© Diodes Incorporated
ADVAN
CE I
N
F
O
RM
ATI
O
N
DC Test Circuits
Fig. 1 Test Circuit for V
Z
= V
REF
Fig. 2 Test Circuit for V
Z
> V
REF
Fig.3 Test Circuit for Off State Current
Deviation of reference input voltage, V
DEV
, is defined as the maximum variation of the reference input voltage over the full
temperature range.
The average temperature coefficient of the reference input voltage, V
REF
is defined as:
) 2 T 1 T ( V
1000000 V
) C / ppm ( V
ref
dev o
ref −
×
=
The dynamic output impedance, RZ is defined as:
z
z
z
I
V
R
Δ
Δ
=
When the device is programmed with two external resistors,
R1 and R2, (Fig 2), the dynamic output impedance of the
overall circuit, R’, is defined as:
)
2 R
1 R
1 ( R R
z
+ = ′
Input
I
L
I
REF
I
Z
V
Z
V
REF
Input
I
L
I
REF
I
Z
V
Z
V
REF
R1
R2
Input
I
ZOFF
V
Z
T1 T2 Temperature
V = V - V
DEV MAX MIN
V
MAX
V
MIN