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1.01

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AS3610/11

Datasheet - D e t a i l e d D e s c r i p t i o n

8.1.8

NTC supervision

This charger block also features a supply for an external NTC resistor to measure the battery temperature while charging. If the temperature is

too high (voltage on NTC pin is below VBATTEMP_ON) the charger will stop operation (stop_charging=1).

When the battery temperature drops, the voltage on NTC pin will rise above VBATTEMP_OFF and the charger will start charging again. This is

forming a temperature hysteresis of about 3 to 5°C to avoid an oscillation of the charger.

The levels for switching off the charger (ntc_temp: 45ºC or 55ºC) as well as the type of NTC (ntc_10k: 10k or 100k) can be selected via

register settings. The battery temperature supervision via the NTC can be switched off (ntc_on = 0).

The supply for the NTC will be only on when a charger is detected and ntc_on bit is set.

8.2

Step up converter mode (OTG Boost)

is disabled (XEN=1 or chg_en=0) and the bit boost_en is set (and for AS3611 the pin OTG_BOOST=1). The bit boost_lowcurr selects the output

current capability between 200mA and 500mA.

8.2.1

Softstart of OTG booster

output current is limited below 100mA. After that startup time the full current is available.

8.2.2

Short-circuit and overvoltage protection circuit

- VBAT drops below 2.6V (typ)

- VBUS is above 5.3V (typ)

If one of these conditions is valid for more that 30msec debounce time (debounce_timer=00b), the booster is stopped and the boost_error bit is

set. To restart the booster it’s necessary to set boost_en=0 and 1 again. (For AS3611 the OTG_BOOST pin has to be set to 0 and 1 again).

If the die Temp is above 140deg the booster is stopped and restarted automatically when the die temperature drops.

8.3

2-Wire-Serial Control Interface

8.3.1

Feature List

Fast-mode capability (max. SCL-frequency is 400 kHz)

7+1-bit addressing mode

60h x 8-bit data registers (word address 0x00 - 0x60)

Write formats: Single-Byte-Write, Page-Write

Read formats: Current-Address-Read, Random-Read, Sequential-Read

SDA input delay and SCL spike filtering by integrated RC-components

8.3.2

Protocol

Table 4. 2-Wire Serial Symbol Definition

Symbol

Definition

RW

Note

S

Start condition after stop

R

1 bit

Sr

Repeated start

R

1 bit

DW

Device address for write

R

1000 1100b (8Ch)

DR

Device address for read

R

1000 1101b (8Dh)

WA

Word address

R

8 bit

A

Acknowledge

W

1 bit

N

No Acknowledge

R

1 bit