Texas Instruments BQ2461X Battery Charger User Manual


 
Introduction
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1 Introduction
1.1 EVM Features
Evaluation Module For bq2461x/bq2463x
High Efficiency Synchronous Buck Charger
User-programmable up to 26V Battery Voltage
AC Adapter Operating Range 5 V–28 V
LED Indication for Control and Status Signals.
Test Points for Key Signals Available for Testing Purpose. Easy Probe Hook-up.
Jumpers Available. Easy to Change Connections.
1.2 General Description
The bq2461x is highly integrated Li-ion or Li-polymer switch-mode battery charge controllers. The
bq2463x is highly integrated switch-mode battery charge controllers designed specifically to charge
Lithium Phosphate battery chemistries.
They offer a constant-frequency synchronous PWM controller with high accuracy charge current and
voltage regulation, adapter current regulation, termination, charge preconditioning, and charge status
monitoring,
The bq2461x/bq2463x charges the battery in three phases: preconditioning, constant current, and
constant voltage. Charge is terminated when the current reches a minimum user-selectable level. A
programmable charge timer provides a safety backup for charge termination. The bq2461x/bq2463x
automatically restarts the charge cycle if the battery voltage falls below an internal threshold, and enters a
low-quiescent current sleep mode when the input voltage falls below the battery voltage.
The dynamic power management (DPM) function modifies the charge current depending on system load
conditions, avoiding ac adapter overload.
High accuracy current sense amplifiers enable accurate measurement of the ac adapter current, allowing
monitoring of overall system power.
For details, see bq24610 and bq24617 (SLUS892), bq24616 (SLUSA49) and bq2463x (SLUS894) data
sheets.
1.3 I/O Description
Table 1. I/O Description
Jack Description
J1–DCIN AC adapter, positive output
J1–GND AC adapter, negative output
J2–VEXT External power supply, positive output
J2–GND External power supply, negative output
J2–TTC Timer capacitor pin
J3–ACSET Input current program pin
J3–ISET1 Charge Current Program Pin
J3–ISET2 Pre-charge/Termination program pin
J3–GND Ground
J–PG Power Good (active low)
J4–CHGEN Charge enable
J4–VREF IC reference voltage VREF
J4–TS Temperature Qualification Voltage Input
J5–VSYS Connected to system
J5–VBAT Connected to battery pack
2
bq2461x/bq2463x EVM (HPA422) Multi-Cell Synchronous Switch-Mode Charger SLUU396A–January 2010–Revised July 2010
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