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Revision 0.7

29 - 42

with additional features

with photosensor

AS3636

Preliminary Datasheet, Confidential - D e ta i l e d D e s c r i p t i o n

Table 17. Xenon Config Register A

Addr: 0Dh

Xenon Config Register A

Define the end of charge detection voltage

Bit

Bit Name

Default Access

Description

5:0

charge_voltage_selection

NVM

R

Define the Xenon end of charge detection voltage

(measured on pin SW_F)

00h

28.5V

01h

28.6V

02h

28.7V

...

3Fh

34.8V

7:6

00b

R

always 0, don’t use

Table 18. Xenon Config Register B

Addr: 0Eh

Xenon Config Register B

Define the peak current limit for the Xenon charger

Bit

Bit Name

Default Access

Description

2:0

switch_current_selection

1

NVM

R

Peak current limit measured on pin SW_F

000

375mA

001

450mA

010

525mA

011

600mA

100

675mA

101

750mA

110

825mA

111

900mA

6:3

extend_pulse

NVM

R

Extend the timing for the IGBT strobe pulse - see IGBT

Pulse Timing adjustment

0h

no pulse extension

1h

100ns

2h

200ns

3h

300ns

...

...

Eh

1400ns

Fh

1500ns

7

IGBT_fall2zero_slow

NVM

R/W

Define together with IGBT_fall_speed2zero IGBT driver fall

speed for final switch-off (VOUTBOOST/2 to 0V)

0

full current - see IGBT_fall_speed2zero

1

half current - see IGBT_fall_speed2zero

1. Take care to set the peak current limit to fit to the Xenon charger transformer used - if the peak current limit is

set too low, efficiency will drop and eventually end of charge will not be reached anymore.