DS2780 Maxim Integrated Products, DS2780 Datasheet - Page 16

• Manufacturer Part Number: DS2780
• Description: Stand-Alone Fuel Gauge IC
• Manufacturer: Maxim Integrated Products

www.DataSheet4U.com
Calculation of Results
STATUS REGISTER
The STATUS register contains bits which report the device status. The bits can be set internally by the DS2780.
The CHGTF, AEF, SEF, LEARNF and VER bits are read only bits which can be cleared by hardware. The UVF and
PORF bits can only be cleared via the 1-Wire interface.
Figure 13. Status Register Format
Address
Field
CHGTF
AEF
SEF
LEARNF
Reserved
UVF
PORF
Reserved
* - This bit can be set by the DS2780, and may only be cleared via the 1-Wire interface.
** - LEARNF is only cleared if ACR reaches 0 after VOLT < VAE.
RAAC [mAh] = (ACR[mVh] - AE(T) * FULL40[mVh]) * RSNSP [mhos]
RSAC [mAh] = (ACR[mVh] - SE(T) * FULL40[mVh]) * RSNSP [mhos]
RARC [%] = 100% * (ACR[mVh] - AE(T) * FULL40[mVh]) /
RSRC [%] = 100%* (ACR[mVh] - SE(T) * FULL40[mVh]) /
01h
Bit
7
6
5
4
3
2
1
0
Read / Write *
Read / Write *
Read Only
Read Only
Read Only
Read Only
Read Only
Read Only
Format
Bit Definition
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 Flag – When 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
Under-Voltage Flag
Set to 1 when: VOLT < V
Cleared to 0 by: User
Power-On Reset Flag – Useful for reset detection, see text below.
Set to 1 upon Power-Up by hardware.
Cleared to 0 by: User
Undefined
{(AS * FULL(T) - AE(T)) * FULL40[mVh]}
{(AS * FULL(T) - SE(T)) * FULL40[mVh]}
16 of 27
( CHGTF = 1 ) OR ( CURRENT < 0 ) OR
SLEEP
DS2780 Stand-Alone Fuel Gauge IC