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Up Dn

Sense

V =12V

I

V 1=3.3V

O

V 2=1.8V

O

I 2

O

ASIC

VC ORE

VC CI O

PTH12010L

1

10

4

6

2

3

9

GND

Inhibit

7

Vadj

+

R1

2kW

R2

130 W

C2

330 F

m

C4

330 F

m

C6

0.68 F

m

C5

0.1 F

m

C3

330 F

m

C1

330 F

m

+

+

PTH12020W

7

10

4

5

6

2

3

9

Tra ck

V

I

V

I

V

O

V

O

GND

Inhibit

1

Adjust

+

TL7702B

V

CC

GND

SENSE

RESIN

REF

CT

RESET

RESET

8

7

2

1

3

5

6

4

+

R5

10k0

R4

100kW

R3

11k0

8

8

Sense

Track

5

MARGIN UP/DOWN CONTROLS

D %

R

orR

=

U

D

499

-99.8kW

(2)

PTH12030W/L

SLTS211F – MAY 2003 – REVISED FEBRUARY 2007

Figure 19. Application Circuit Demonstrating Prebias Startup

The PTH12060, PTH12010, PTH12020, and PTH12030 products incorporate Margin Up and Margin Down

nominal 5%. This provides a convenient method for dynamically testing the operation of the load circuit over its

supply margin or range. It can also be used to verify the function of supply voltage supervisors. The

±5% change

low-leakage open-drain device, such as an n-channel MOSFET or p-channel JFET is recommended for this

inputs. The value of the resistor can be selected from Table 6, or calculated using the following formula.

MARGIN UP/DOWN ADJUST RESISTANCE CALCULATION

formula is as follows.

Where

∆% = The desired amount of margin adjust in percent.

19

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