IP9001

4-CH MOTOR DRIVE IC FOR PORTABLE CDP

- 14 -

www.interpionsemi.com

APPLICATION SUMMARY (Continued)

- Short circuit protection

When the output voltage of error amp holds

“H” status, then IP9001 starts charging to “CSPRT” with

constant current

“ISPRT”.

If the voltage of the CSPRT rises above 1.2V, then the DC/DC converter circuit is disabled.

Disable time is dependent on the external capacitor

“CSPRT” , Threshold voltage “VTH”, and internal

constant current source

“ISPRT”.

* VTH=1.2V, ISPRT=10uA

( se c)

V TH

t

C S PRT

I S PRT

=×

- Soft start circuit

IP9001 accomplishes soft-start-function by attaching external capacitor between DEAD pin and GND.

Maximum duty can be changed by adding external resistor to DEAD pin (pin 4).

(

int

Re

)(sec)

t

C DEAD

R

xt

=

×+

* Rint=65K ohm, Rext=external resistor

- Power off function

When the input voltage of OFF(pin40) is low, then IP9001 starts charging to

“CSPRT” with

constant current

“IOFF”.

If the voltage of the CSPRT rises above 1.2V, then the DC/DC converter circuit is disabled.

Disable time is dependent on the external capacitor

“CSPRT” , Threshold voltage “VTH”,

and internal constant current source

“IOFF”.

* VTH=1.2V, IOFF=20uA

( s e c)

VTH

t

C S P RT

I O FF

=×

- Over voltage protection

When the sensing voltage of SENS(pin1) is above 8.4V, then IP9001 starts charging to

“CSPRT” with

constant current

“IHV”.

If the voltage of the CSPRT rises above 1.2V, then the DC/DC converter circuit is disabled.

Disable time is dependent on the external capacitor

“CSPRT” , Threshold voltage “VTH”,

and internal constant current source

“IHV”.

* VTH=1.2V, IOFF=20uA

( s ec)

V TH

t

C S P RT

I HV

=×