DV2057_14 Datasheet, PDF (1/6 Pages) Texas Instruments – Advanced Li-Ion Charger Development System Control of On-Board Linear Regulator

DV2057/C/T/W
Advanced Li-Ion Charger Development System
Control of On-Board Linear Regulator
Features
➤ bq2057 charge-control evaluation and development
system for single- and dual-cell Li-Ion packs with
coke or graphite anodes
➤ Optional temperature monitoring before and during
charge
➤ Proprietary AutoComp charge-rate compensation
➤ Integrated trickle-charge for conditioning deeply
discharged batteries
➤ Regulated charge current and voltage
➤ Charge status output for LED or host-processor
interface to indicate charge-in-progress,
full-capacity, and fault conditions
➤ Automatic battery-re-charge feature
➤ Charge termination by minimum current
➤ Direct battery connection
➤ 500mA charge rate
➤ High-side current sensing
General Description
The DV2057/C/T/W are complete development and
evaluation environments for bq2057 series advanced
Li-Ion linear charge management ICs. The DV2057 fam-
ily supports both single- and dual-cell Li-Ion packs with
coke or graphite anodes:
approximately 10% of the regulation current. The condi-
tioning current also minimizes heat dissipation in the
external pass element during the initial stage of charge.
Once the battery voltage reaches the internal threshold,
V_MIN, full charge begins. The DV2057/C/T/W complete
the charge cycle in two phases. While the pack is below
the regulation voltage, a constant-current phase replen-
ishes approximately 70% of battery capacity. An accu-
rate voltage-regulation phase completes the charge. The
DV2057/C/T/W terminate charge when the current ta-
pers off to the V_TERM threshold.
These boards feature the proprietary AutoComp tech-
nique to compensate safely for the internal impedance of
the battery. The AutoComp resistors, R_COMP1, and
R_COMP2, must be set according to the characteristics of
the battery.
Before using these development boards, please review
the bq2057 data sheet.
Part Number
DV2057
DV2057C
DV2057T
DV2057W
Regulation Voltage
4.1V
4.2V
8.2V
8.4V
Full charge is preceded by charge qualification based on
battery temperature and voltage. The DV2057/C/T/W
suspend charge if the battery temperature is outside the
V_TS1 to V_TS2 thresholds and wait until the battery tem-
perature is within the allowed range. The
DV2057/C/T/W also check the battery voltage. If the bat-
tery voltage is below the low-voltage threshold, V_MIN, the
DV2057/C/T/W use trickle charge to condition the bat-
tery. The conditioning charge rate, I_COND, is set at
SLUU056A - JANUARY 2000
Connection Descriptions
J1
DC+
DC-
J2
BAT+
BAT-
J3
TEM+
INH
Charger supply positive
Charger supply ground
Positive battery terminal
Negative battery terminal
Thermistor connection
Charge inhibit input
1