SGS Thomson Microelectronics ST3S01LED Datasheet

■ DEDICATED I.C. FOR 1 LI-ION CELL OR 3

NI-MH CELLS

■ 5 DIFFERENT OPERATING MODES

■ 150 mA PRECHARGE CURRENT

■ VERY LOW DRO P CHARGE SWITCH

(130mV @ 800mA)

■ VERY LOW DROP REVERSE SWITCH

(130mV @ 800mA)

■ 5.7V OVER BATTERY OVER VOLTAGE

PROTECTION

■ CHARGER DETECTION MODE

■ (V

CHARGE-VBATT

)DETECTIONMODE

DESCRIPTION

This specification describes a dedicated I.C. which allows to charge 1 Lilon cell or 3 Nimh cells. The principle used to charge the batteries is the pulsed current, the monitoring is operated by the micro-contoller of the application. This I C integrates one Power Switch and achieves the

ST3S01LED

BATTERY CHARGE I.C.

SO-8

exposed pad

charge bat teries in two different modes charg e or precharge. One of this operating m ode (charge or precharge) can be sel ec ted in a static or pulsed way by one I/ O from a micro-controller. The I C can supply power to accessories controlled by this I.C. in Reverse mode. The I.C. is available in the smaller and surface mounted S O-8 (exposed pad version) package.

SCHEMATIC DIAGRAM

1/17March 2003

ST3S01LED

ABSOLUTE MAXIMUM RATINGS

Symbol Parameter Value Unit

BATT

CHARGE

FLAG

CHARGER-OK

CMD-PWM

CMD-MODE

CMD-REVERSE

SWITCH

stg

AMB

Absolute Maximum Ratings are those values beyond which damage to the device may occur. Functional operation under these condition is not implied. (*) The I.C. is automatically turned OFF when V falling edge)

Battery Voltage Charge Voltage (*) (V

CHARGE-VBATT

) Flag Control Voltage Charger Flag Control Voltage PWM Command Voltage CMD Command Voltage Reverse Command Voltage Internal Switch

Continuous Max Current Internal Switch Peak

Current

= 85°C, R

AMB

= 30°C, R

AMB

thj-amb thj-amb

= 40°C/W = 40°C/W

T<1ms Duty Cycle < 1%

thj-amb

= 40°C/W

Storage Temperature Range Operating Junction Temperature Range Operating Ambient Temperature Range (if an adeguate

heatsink is provided)

reaches typically 14V (V

CHARGE

-0.3 to 6 V

-12 to 16 V

-0.3 to 12 V

-0.3 to 5 V

-0.3 to 5 V 2A 3A 8A

-55 to +125 °C

-40 to +125 °C

-40 to +85 °C

rising edge); typical hysteresis is 700mV (V

CHARGE

THERMAL DATA

Symbol Parameter SO-8 Unit

thj-case

Thermal Resistance Junction-case

10 °C/W

ORDERING CODES

TYPE SO-8 exposed pad SO-8 exposed pad (T&R)

ST3S01LED ST3S01LED ST3S01LED-TR

CONNECTION DIAGRAM (top view)

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PIN DESCRIPTION

Pin N° Symbol Name and Function

BATT

2 CMD-REVERSE Reverse Command pin: Enables the reverse mode when connected to a positive

3 CMD-PWM PWM Command pin: allows to control the precharge or charge switch in PWM

4 CMD-MODE Mode Command pin: allows to switch between precharge and charge mode (refer

5 GND GND Pin 6 CHARGER-OK CHARGER-OK output pin; open drain N-channel MOSFET that is in high

7 FLAG FLAG pin (V

CHARGE

BATTERY pin: input pin when reverse mode is selected; output pin when in charge or precharge mode

voltage higher than 1.2V. Logic pin internally pulled down.

mode (refer to the Table 1 for the different operating modes). Logic pin internally pulled down.

to OPERATING MODES Table). Logic pin internally pulled down.

impedance when the V

CHARGE

voltage drops below 2.5V and CMD-REVERSE is

low. When the reverse function is activated, this open drain have the same information of the (V

when the V

CHARGE-VBATT

CHARGE

CHARGE-VBATT

): open drain N-channel MOSFET that sinks current

voltage is higher than the V

) FLAG.

CHARGER SUPPLY pin: input pin when charge or precharge mode is selected; output pin when in reverse mode.

BATT

ST3S01LED

OPERATING MODE

CMD-PWM CMD-MODE Operating Function Selected

0 0 PRECHARGE MODE (Default state) 0 1 CHARGE MODE 1 0 CHARGE and PRECHARGE switches are open 1 1 CHARGE and PRECHARGE switches are open

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ST3S01LED

I.C. BLOCK DIAGRAM

POSSIBLE OPERATING MODES

Five different operating m odes are allowed: charge, precharge, reverse, charge+reverse and precharge+reverse. These op erating modes can be achieved by properly selection of the CMD-REVERSE C MD-PWM and CMD-MODE (See POSSIBLE OPERATING MODE Table).

PRECHARGE MODE

The PRE CHARGE function is compos ed by a switch and a 100mA current source which fully works for V

CHARGE

higher than 2.5V. When the CMD-MODE and the CMD-PWM are not leaded the switc h is ON, being the i nput states held by an internal pull down resistor. This is used when the

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battery is strongly discharged. In this case V

BATT

can be null (battery empty) and all the i nput pins are not held by any level (because the micro-controller is down), except the V

CHARGE

pin which is a main supply. The source of current supplies a const ant current into the battery till its voltage level reaches the required level allowing to start the micro-controller (typically 3V ). The current direction is from V

CHARGE

to V

BATT

.The reverse leakage current when the swich is ON must be null; this is obtained thanks t o an internal circuitry that switch OFF the internal P-MOS when the V

is higher than V

BATT

CHARGE

,whateverthe status of the CMD -MO D E. The precharge function is also used to adjust the mean current. When the

ST3S01LED

battery is fully charged the current into the battery has not to be more than C/25 (Nimh battery). In order to perform finely this, the CMD-PWM pin must be d riven with PWM funct ion (in the same time, the CMD-MODE must be kept low). T he duty cycle allows to adjust the mean current needed.

CHARGE MODE

TheCMD-MODEpin,whenhigh(andCMD-PWM low), handles t he switch in charge mode. This switch allows the battery charge with a strong current. The drop of this internal P -Channel MOS is very low (200mV @ 800mA ) in order to optimize the efficiency of the charge.

The switch is not internally protected against short circuit or overcurrent condition.

When the s witch is ON (CMD-MODE high and CMD-PWM low), the current direction into the chip is from V

CHARGE

to V

. The reverse current

BATT

when the switch is ON m us t be null; t his is obtained by mean of an internal circu itry that switch OFF the internal P - MOS when the V higher than V

CHARGE

, whatever the status of the

BATT

CMD-MODE. When the CMD-MODE pin is lo w or in high impedance t he switch is OFF, while it is ON when the signal on that pi n is high.

REVERSE MODE

When the reverse function i s selected by CDM-REVERSE pin, the switch allows to supply the accessories with a strong current. The drop of the internal P-Channel MOS is very low (200mV @ 800mA)and theswitchproperlywork for V

BATT

higher than 2.5V. This allows to supply energy on the V

CHARGE

pin. When the switch is ON (CMD-REVERSE high ) the current direction into thechipisfromV The reverse current (from V

BATT

to V

CHARGE

to V

BATT

when the switch is ON m us t be null; t his is obtained by mean of an internal circu itry that switch OFF the internal P-MOS when the V

CHARGE

is higher than V

, whatever the

BATT

status of the CMD-REVERSE. When the level of CMD-REVERSE pin is low or in high impedance, the switch is OFF, while it is ON when the signal on CMD-REVERSE pin is high.

OVERVOLTAGE PROTECTION

This function allows to held the switches OFF when the voltage level on V

is higher than a

BATT

maximum voltage whatever are the values of CMD-PWM, CMD-MODE and CMD-REVERSE. This maximum volt age is shown in the electrical characteristic (typical threshold 5.7V). From the moment in which the o.v.protection is activated, it

will be possible to turm ON again the switch only when th e V

CHARGE

value decreases down to 2.5V typically, it doesn't matter which operation mode is selected. The protection works only when the battery is in charge or precharge mode, i.e. V

CHARGE>VBATT

. This represent s, in fact, the typical application condition where the battery could increase its value, i.e. When charge or precharge mode are used.

CHARGER DETECTION MODE

This function allows to generate a digital signal (CHARGER-OK) to indicate if the V voltage is higher than 2.5V and the revers e function is inactive. This functionality allows to determine if the charger is present or not; if t he V

CHARGE

is lower than the 2.5V, the CHARGER-OK goes into high impedance (open drain). When the reverse function is act ive, this open drain have the V

CHARGE-VBATT

This circuitry is d irectly supplied from V and works only for V

CHARGE-VBATT

DETECTION MODE

CHARGE

higher than 2.2V.

This function allows to generate a digital signal (V

CHARGE-VBATT

voltage is higher than V lower than the V

)flagtoindicateiftheV

;iftheV

BATT

, this open drain goes into

BATT

high impedance s tate. This circuitry is directly supplied from V V

CHARGE

higher than 2.2V.

CHARGE

pin an d works only for

THERMAL PROTECTION

An internal thermal shutdown circuitry will switch OFF the P_MOS, only in precharge or in charge mode, when the junction temperature reaches typically 180°C. This has been impl emented in

)

order to protect the device from overburning. 20°C of thermal hysteresis will avoid a thermal oscillation. This circuitry is supplied from V

CHARGE

acts only on t he prec harge and c harge s witche s.

ESD PROTECTION

Both V

CHARGE

and V

pins are protected

BATT

against electrostatic discharge up to ±4KV (HBM, MIL STD 833D.

CHARGE VOLTAGE

CHARGE

to12V.AtV

functional operating range is from 2.5V

CHARGE

=14V typically the I.C. is automatically turned OFF and remains OFF up to 16V. A V

CHARGE

voltage higher than 16V can

damage the IC.

CHARGE

information.

CHARGE

and, so,

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ST3S01LED

POSSIBLE OPERATING MODE

CMD-PWM CMD-MODE CMD-REVERSE Operating Function Selected

0 0 0 PRECHARGE 0 0 1 PRECHARGE + REVERSE 0 1 0 CHARGE 0 1 1 CHARGE + REVERSE 1 0 0 SWITCH OPEN 1 0 1 REVERSE 1 1 0 SWITCH OPEN 1 1 1 REVERSE

ELECTRICAL CHARACTERISTICS OF REVERSE SWITCH (T

= - 40 to 85°C, unless otherwise

specified.)

Symbol Parameter Test Conditions Min. Typ. Max. Unit

BATT

DROP

LEAKAGE

CMD-REV

ON-OFF

Reverse Block Operating

2.5 6 V

Input Voltage Dropout Voltage V

Reverse Leakage Current (from V

CHARGE

tested on V

to V

BATT

pin)

BATT

CMD-REVERSE Logic High (Switch ON)

CMD-REVERSE Logic Low (Switch OFF)

CMD-REVERSE Logic Typical Threshold

CMD-REV Input Current V

=3V I

BATT

CMD-REVERSE

CMD-MODE

=0V V

BATT

CMD-REVERSE

CMD-MODE

=3V I

BATT

CMD-PWM

=3V I

BATT

CMD-PWM

=3V I

BATT

CMD-PWM

=3V I

BATT

CMD-REVERSE

CMD-MODE

=5V I

BATT

CMD-REVERSE

CMD-MODE

=1.9V, V

=1.9V

=1.9V, V

=1.9V

=1.9V V

=1.9V, V

=1.9V

=1.9V, V

=1.9V

REVERSE

CMD-PWM

CHARGE CMD-PWM

REVERSE

CMD-MODE

REVERSE

CMD-MODE

REVERSE

CMD-MODE

REVERSE

CMD-PWM

REVERSE

CMD-PWM

=800mA

=1.9V

=9V

=1.9V

=10mA

=1.9V

=10mA

=1.9V

=10mA

=1.9V

=10mA

=1.9V

=10mA

=1.9V

130 200 mV

01µA

1.2 V

0.4 V

0.75 V

1 1.9 3 µA

10 µA

Response Time 100 µs

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