LTC2910

9

2910fb

APPLICATIONS INFORMATION

R

V

R

B

m

A

=−

(2)

steps must be recalculated.

Positive Voltage Monitor Example

A positive voltage monitor application is shown in Figure

3. The monitored voltage is a 5V ±10% supply. Nominal

current in the resistive divider is 10µA.

R

V

µA

V

V

k

05

10

5

45

56 2

.

•

.

.

R

V

µA

kk

≈

5

10

56 2

499

.

Negative Voltage Monitor Example

A negative voltage monitor application is shown in Figure

4. The monitored voltage is a –5V ±10% supply. Nominal

current in the resistive divider is 10µA. For the negative

R

V

µA

VV

VV

k

−

−

≈

05

10

51

45

1

54 9

.

•

–

–.

.

R

VV

µA

kk

−

−≈

–

.

51

10

57 6

549

Power-Up/Down

The LTC2910 is guaranteed to assert ⎯R⎯S⎯T low and RST

started. After an adjustable delay time, RST pulls low and

⎯R⎯S⎯T weakly pulls high.

Threshold Accuracy

Reset threshold accuracy is important in a supply sensitive

system. Ideally, such a system would reset only if supply

Figure 3. Positive Supply Monitor

2910 F02

449k

56.2k

5V

± 10%

RST

RST

SEL

V7

5V

GND

LTC2910

Figure 4. Negative Supply Monitor

2910 F04

54.9k

549k

–5V

± 10%

RST

RST

SEL

REF

V7

5V

GND

LTC2910