Maxim Integrated MAX20335, Manual

Page: 37 / 67

Figure 5b. Battery Charger State Diagram (JEITA Monitoring with Charger Shutdown)
MAX20335 PMIC with Ultra-Low I
Q
Voltage Regulators and
Battery Chargers for Small Lithium Ion Systems
www.maximintegrated.com
Maxim Integrated │ 37
MAINTAIN
CHARGE DONE
ChgStat =110
LED=OFF
I
CHG
=0
CHARGER OFF
ChgStat =000
LED=OFF
I
CHG
=0
PREQUAL
ChgStat =010
LED=ON
I
CHG
=I
PCHG
FAST
CHARGE
(CONSTANT CURRENT )
ChgStat =011
LED=ON
I
CHG
=I
FCHG
**
FAST
CHARGE
(CONSTANT VOLTAGE )
ChgStat =100
LED=ON
I
CHG
=I
FCHG
MAINTAIN
CHARGE
ChgStat =101
LED=ON
I
CHG
<I
CHG_DONE
FRESH BATTERY
INSERTION
ChgStat =110
LED=1s pulse
I
CHG
=0
CHARGE SUSPEND
ChgStat =001
LED=1.5s period
I
CHG
=0
FAULT
ChgStat =111
LED=0.15s PERIOD
I
CHG
=0
PREQUAL SUSPEND
ChgStat =001
LED=1.5s PERIOD
I
CHG
=0
FAST
CHARGE
CC SUSPEND
ChgStat =001
LED=1.5s PERIOD
I
CHG
=0
FAST
CHARGE
CV SUSPEND
ChgStat =001
LED=1.5s PERIOD
I
CHG
=0
ChgEn =1
AND
V
SYS
>V
SYS_LIM
RISE
V
BAT
>V
BAT_PChg
RESET CHARGE TIMER
V
BAT
<V
BAT_PChg
RESET CHARGE TIMER
VOLTAGE MODE =1*
AND
V
SYS
>V
SYS_LIM
RISE
(VOLTAGE MODE =0*
AND V
SYS
>V
SYS_LIM
RISE)
OR V
BAT
<V
BAT_PChg
RECOVER FROM FAULT
RESET CHARGE TIMER
T1<T<T4
T<T1 or T>T4
T1<T<T4
T<T1 or T>T4
T1<T<T4
T<T1 or T>T4
RESET CHARGE TIMER
T1<T<T4
T<T1 or T>T4
T<T1 or T>T4
T<T1 or T>T4
ChgEn =1,
V
BAT
> V
BATREG
– V
BATRECHG
ChgEn =1,
V
BAT
>V
BATREG
–V
BATRECHG
Freshbat _dis=0
I
CHG
>I
CHG_DONE
ChgAutoStp =0"
RESET CHARGE TIMER
I
CHG
<I
CHG_DONE
AND
V
SYS
>V
SYS_LIM
RISE
AND
T
DIE
<T
CHG_LIM
RESET CHARGE TIMER
t
CHG_TIMER
>t
MTCHG
AND
ChgAutoStp =1
V
BAT
<V
BATREG
–V
BATRECHG
and ChgAutoReSta =1
And V
SYS
>V
SYS_LIM
RISE
RESET CHARGE TIMER
PAUSE
CHARGE
TIMER
PAUSE
CHARGE
TIMER
PAUSE
CHARGE
TIMER
t
CHG_TIMER
>t
PCHG
t
CHG_TIMER
>t
FCHG
T
DIE
<T
BUS_LIM
or V
BAT
>V
SYS
or ChgEn =0
FROM ANY STATE
NOTES :
* VOLTAGE MODE IS AN INTERNAL SIGNAL
** CHARGE TIMER IS SLOWED BY 50% IF I
CHG
< I
FCHG
/2 AND PAUSED IF I
CHG
< I
FCHG
/5 ONLY IN FAST CHARGE CONSTANT
CURRENT STATE WHERE I
FCHG
IS THE EFFECTIVE FAST CHARGE CURRENT INCLUDING JEITA CURRENT LIMITATION
T<T2 or T>T3
V
BAT
<V
BATREG
–V
BATRECHG
1s
t
MTCHG