HT70XXA-1

Rev. 1.40

7

January 26, 2006

· with 5V voltage regulator

Change of Detectable Voltage

If the required voltage is not found in the standard

product selection table, it is possible to change it by

using external resistance dividers or diodes.

· Varying the detectable voltage with a resistance di-

vider

Detectable voltage =

R+ R

R

AB

B

´ VDET

Hysteresis width =

R+ R

R

AB

B

´ VHYS

· Varying the detectable voltage with a diode

Detectable Voltage = Vf1+Vf2+VDET

Malfunction Analysis

The following circuit demonstrates the way a circuit

analyzes malfunctions by monitoring the variation or

spike noise of power supply voltage.

Charge Monitoring Circuit

The following circuit shows a charged monitor for

protection against battery deterioration by

overcharging. When the voltage of the battery is higher

than the set detectable voltage, the transistor turns on to

bypass the charge current, protecting the battery from

overcharging.

H T 7 0 4 4 A - 1

V S S

V D D

H T 7 1 5 0 - 1

V O U T

V I N

G N D

5 V

5 V V o l t a g e r e g u l a t o r

H T 7 0 X X A - 1

V S S

V I N

V S S

V O U T

V D D

R A

R B

H T 7 0 X X A - 1

V D D

V I N

V S S

V f 1

V f 2

V O U T

V S S

H T 7 0 X X A - 1

V O U T

V S S

V D D

V S S

H T 7 0 X X A - 1

V D D

V O U T

V S S

L o a d

B A T T

S o l a r

C e l l

T r