User Guide

Background
1-2
1.1 Background
The bqTINY series are highly integrated Li-Ion and Li-Pol linear charge
management devices targeted at space limited portable applications. In a
small package, the bqTINY series offer integrated PowerFET and current
sensor, reverse blocking diode, high accuracy current and voltage regulation,
charge status, and charge termination.
The bqTINY charges the battery in three phases: conditioning, constant
current, and constant voltage. Charge is terminated on the basis of minimum
current. An internal charge timer provides backup safety for charge
termination. The bqTINY automatically restarts the charge if the battery
voltage falls below an internal threshold. The bqTINY automatically enters
sleep mode when V
CC
supply is removed.
In addition to the standard features, different versions of the bqTINY offer a
multitude of additional features. These include temperature-sensing input for
detecting hot or cold battery packs, power good (PG
) output indicating the
presence of the ac adapter, a TTL-level charge enable input (CE
) to disable
or enable the charge process, and a TTL-level timer and termination-enable
(TTE
) input to disable or enable the fast-charge timer and charge termination.
1.2 Performance Specification Summary
This section summarizes the performance specifications of the EVM.
Table 1–1 gives the performance specifications of the EVM.
Table 1–1.Performance Specification Summary
Specification Test Conditions Min Typ Max Units
Input dc voltage, V
I(DC)
V
REG
+0.5 5.0 5.2
†
V
Battery charge current, I
O(CHG)
See note 0.7
†
A
Power dissipation (V
(DC+)
–V
(BAT+)
)*I
(CHG)
1.5 W
†
This input voltage maximum is a function of the maximum allowable power dissipation on the IC. The current level is pro-
grammed for 0.7 amps. If the programmed charge is changed, then the maximum input voltage needs to be adjusted.
P
maxIC
= 1.5 Watt = I
CHG
(V
DC+
– V
BAT+
).