DS2781 Maxim Integrated Products, DS2781 Datasheet - Page 18

• Manufacturer Part Number: DS2781
• Description: 1-Cell or 2-Cell Standalone Fuel Gauge IC
• Manufacturer: Maxim Integrated Products

STATUS REGISTER
Figure 14. Status Register Format
Field
CHGTF
AEF
SEF
LEARNF
Reserved
UVF
PORF
Reserved
* - This bit can be set by the DS2781, and may only be cleared through the 1-Wire interface.
** - LEARNF is only cleared if ACR reaches 0 after VOLT < VAE.
The STATUS register contains bits that report the device status. The bits can be set internally by the DS2781. The
Address
CHGTF, AEF, SEF, LEARNF and VER bits are read only bits that can be cleared by hardware. The UVF and
Bit
7
6
5
4
3
2
1
0
Read / Write *
Read / Write *
01h
Read Only
Read Only
Read Only
Read Only
Read Only
Read Only
Format
PORF bits can only be cleared via the 1-Wire interface.
Allowable Values
Charge Termination Flag
Set to 1 when: ( VOLT > VCHG ) AND ( 0 < IAVG < IMIN ) continuously
for a period between two IAVG register updates ( 28s to 56s ).
Cleared to 0 when: RARC < 90%
Active Empty Flag
Set to 1 when: VOLT < VAE
Cleared to 0 when: RARC > 5%
Standby Empty Flag
Set to 1 when: RSRC < 10%
Cleared to 0 when: RSRC > 15%
Learn Flag¾When set to 1, a charge cycle can be used to learn battery
capacity.
Set to 1 when: ( VOLT falls from above VAE to below VAE ) AND
( CURRENT > IAE )
Cleared to 0 when:
( ACR = 0 **) OR ( ACR written or recalled from EEPROM) OR ( SLEEP
Entered )
Undefined
Undervoltage Flag
Set to 1 when: VOLT < V
Cleared to 0 by: User
Power-On Reset Flag¾Useful for reset detection, see text below.
Set to 1 upon Power-Up by hardware.
Cleared to 0 by: User
Undefined
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( CHGTF = 1 ) OR ( CURRENT < 0 ) OR
SLEEP
Bit Definition