Rainbow-electronics MAX4880 Bedienungsanleitung PDF herunterladen (Seite 5)

MAX4880

Overvoltage-Protection Controller with

Internal Disconnect Switch

_______________________________________________________________________________________ 5

CURRENT LIMIT vs. TEMPERATURE

TEMPERATURE (°C)

CURRENT LIMIT (mA)

MAX4880 toc11

-40 -15 10 35 60 85

100

200

300

400

500

600

700

800

= 5V

BTA

= 5V

BTB

= 3.6V

CURRENT LIMIT vs. V

BTB

(V)

CURRENT LIMIT (mA)

MAX4880 toc12

1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5

100

200

300

400

500

600

700

800

= 5V

BTA

= 5V

Pin Description

Typical Operating Characteristics (continued)

= 5V, TA = +25°C, otherwise noted.)

PIN NAME FUNCTION

1IN

Input. IN is the power input for the overvoltage (OVP) charge pump. Bypass IN to GND with a 1µF or

larger capacitor to achieve 15kV ESD protection.

2 EN

Active-Low Enable Input. Driving EN high turns off the external MOSFET. Pulling EN low activates the

overvoltage-protection circuitry and turns on the external MOSFET.

3 GATE

Gate-Drive Output. GATE is the output of an on-chip OVP charge pump. When V

UVLO

< V

OVLO

GATE is driven high to turn on the external n-channel MOSFET. When V

IN (MIN)

< V

UVLO

or V

OVLO

, GATE is driven low to turn off the external n-channel MOSFET.

4 BTA

Input Terminal for the Internal-Current-Limited Switch. Connect BTA to the source of the external n-

channel MOSFET. BTA is the power input for the entire device (except the OVP charge pump). Bypass

BTA to GND with a 0.1µF capacitor as close to the device as possible.

5CB

Control Input for the Internal-Current-Limited Switch. Drive CB high to leave the internal switch control for

the internal logic. The internal switch turns on and off depending on the battery voltage level. The internal

switch turns off when the battery voltage reaches the BTB trip level (4.2V), and turns back on when the

battery falls by 200mV. Driving CB low turns off the internal switch regardless of the battery voltage.

6 GND Ground

7 BTB

Output Terminal for the Internal-Current-Limited Switch. When the BTB voltage exceeds the trip level

(4.2V), the internal switch opens. The switch closes only when the BTB voltage drops 200mV below the

trip level.

BTB_SNS

Battery-Voltage-Sensing Input. BTB_SNS must be connected to BTB for proper operation. Bypass

BTB_SNS to GND with a 0.1µF capacitor as close to the device as possible.

BAT_OK

Active-Low, Open-Drain, Battery-Voltage-Limit Flag Output. BAT_OK asserts low when the voltage on BTB

exceeds the BTB trip level (4.2V). BAT_OK is disabled when EN goes high.

1 2 3 4 5 6 7 8 9 10

Kommentare zu diesen Handbüchern

Keine Kommentare

Rainbow-electronics MAX4880 Bedienungsanleitung Seite 5

Kommentare zu diesen Handbüchern

Verwandte Produkte und Handbücher für Sensoren Rainbow-electronics MAX4880