Introduction
2
SLVU274E – November 2008 – Revised January 2017
Copyright © 2008–2017, Texas Instruments Incorporated
bq24072/3/4/5/9(T) and bq24230/2 1.5-A Single-Chip Li-Ion and Li-Polymer
Charge Management IC EVM
1
Introduction
The bq2407x and bq2432x powers the system while independently charging the battery. This feature
reduces the charge and discharge cycles on the battery, allows for proper charge termination, and allows
the system to run with an absent or defective battery pack. This feature also allows for the system to
instantaneously turn on from an external power source even when using a deeply discharged battery
pack.
This charger has one input and can be programmed to be used with an adapter or USB port as the power
source for the system. In the USB configuration, the host can select from the two preset input maximum
rates of 100 mA and 500 mA. The charger dynamically adjusts the charge rate based on the system load
to stay within the 100-mA or 500-mA maximum limits. An external resistor, RSET1, sets the magnitude of
the charge current. If the charge current exceeds the available input current, the voltage on the OUT pin
drops to the DPPM threshold or the battery voltage, whichever is higher. The charging current is reduced
to what current is available (I
BAT
= I
IN
–I
OUT
).
The integrated circuit (IC) charges the battery in three phases: conditioning, constant current, and
constant voltage. Charge is terminated based on minimum current. A resistor-programmable charge timer
provides a backup safety for charge termination. The charge automatically re-starts if the battery voltage
falls below an internal threshold. Sleep mode is entered when the supply is removed (Vin drops to the
battery voltage).
2
Considerations When Testing and Using bq24072/3/4/5/9(T) and bq24230/2 ICs
Consider the following noteworthy items while testing and using the bq2403x ICs.
The bq24072/3/4/5/9(T) series targets current above a nominal 500 mA (>350 mA) and the difference are
listed in
Table 1. Ordering Information
Part Number
V
OVP
V
BAT
V
OUT(REG)
V
DPM
Optional
Function
Marking
bq24072RGTR
6.6 V
4.2 V
V
BAT
+ 200 mV
V
O(REG)
– 100 mV
TD
CKP
bq24072RGTT
6.6 V
4.2 V
V
BAT
+ 200 mV
V
O(REG)
– 100 mV
TD
CKP
bq24072TRGTR
6.6 V
4.2 V
V
BAT
+ 225 mV
V
O(REG)
– 100 mV
TD
PAP
bq24072TRGTT
6.6 V
4.2 V
V
BAT
+ 225 mV
V
O(REG)
– 100 mV
TD
PAP
bq24073RGTR
6.6 V
4.2 V
4.4 V
V
O(REG)
– 100 mV
TD
CKQ
bq24073RGTT
6.6 V
4.2 V
4.4 V
V
O(REG)
– 100 mV
TD
CKQ
bq24074RGTR
10.5 V
4.2 V
4.4 V
V
O(REG)
– 100 mV
ITERM
BZF
bq24074RGTT
10.5 V
4.2 V
4.4 V
V
O(REG)
– 100 mV
ITERM
BZF
bq24075RGTR
6.6 V
4.2 V
5.5 V
4.3 V
SYSOFF
CDU
bq24075RGTT
6.6 V
4.2 V
5.5 V
4.3 V
SYSOFF
CDU
bq24075TRGTR
6.6 V
4.2 V
5.5 V
4.3 V
SYSOFF
OEC
bq24075TRGTT
6.6 V
4.1 V
5.5 V
4.3 V
SYSOFF
OEC
bq24079RGTR
6.6 V
4.1 V
5.5 V
4.3 V
SYSOFF
ODI
bq24079RGTT
6.6 V
4.1 V
5.5 V
4.3 V
SYSOFF
ODI
bq24079TRGTR
6.6 V
4.1 V
5.5 V
4.3 V
SYSOFF
OED
bq24079TRGTT
6.6 V
4.1 V
5.5 V
4.3 V
SYSOFF
OED
The bq24079(T) ICs are regulated to 4.1 V. The "T" version uses a voltage-based TS bias, which allows
more flexibility in setting the temperature range, whereas the bq24072/3/4/5 ICs use current-biased TS.
The bq24230/2 family is identical to the bq24073/4 ICs except that they are trimmed and their target
current values nominally are at 300 mA (<450 mA). This family is suited for headset designs. The pinout of
each IC is the same across both families except pin 15 (JMP2 on the EVM); the pin 15 function is listed in
under the
Optional Function
column.
