pt6105 China Resources Powtech (Shanghai) Co., Ltd, pt6105 Datasheet - Page 12

• Manufacturer Part Number: pt6105
• Description: Multi-cell Battery Management Front End With I 2 C Interface
• Manufacturer: China Resources Powtech (Shanghai) Co., Ltd

Watchdog for MCU
The PT6105 monitors the communication function
between the I
activity observed from the MCU for about 2sec. two
external MOSFETs are turned off by MCU
Discharge Short Circuit Protection
When PT6105 detects a discharge short circuit
condition, both power MOSFETs are turned off and the
DSC bit is set “1”. The DSC bit is reset after this bit is
read by MCU. MCU can turn on the MOSFETs at any
time but should turn on the load monitor function to
detect that the short circuit condition has been removed.
Load Monitor on Short Circuit
The load monitoring and protection function is
primarily used to guarantee that the load (mostly the
motor) has been removed following an over-current or
short circuit protection during discharge. This function
will prevent the MOSFET from turning on while the
short circuit is still present. As the benefit, the battery is
avoided from starting discharge to a short circuit load.
The load protection mechanism could be enabled or
disabled by the MCU by setting LDMONEN bit as “1”
or “0” in the configuration register. The discharge
MOSFET will be switched off if short circuit load is
detected during discharge, the LDFAIL bit in the status
register will be set to “1” if the short circuit load is still
connected under short circuit condition. When MCU
detected this bit is “1”, both MOSFETs will be tuned
off and discharging procedure is terminated. This bit is
self-reset after the short circuit condition is removed.
Other Protections
- The PT6105 could sustain a <1ms negative
down-to-ground glitch from the battery pack at the start
of discharge.
- VIN =5.7V triggers under-voltage lockout (UVLO).
The UVLO bit in the status register is set as “1”, and
MOSFETs are turned off. All analog functions in the
PT6105 are also turned off. The UVLO bit will be reset
if VIN rises above the UVLO threshold with a
hysteresis.
- Power on reset function (POR = 1.5~2.0). Right after
power on and then VIN above POR, all digital registers
are guaranteed to be reset at the default sleep mode,
waiting for the wake up signal from the MCU.
ADC
China Resources Powtech (Shanghai) Limited
PT6105_DS Rev EN_1.1
2
C interface and MCU. If there is no
.
WWW.CRPOWTECH.COM
The ADC has 10-bit accuracy, sampling 7 battery
voltages and environment temperature alternatively.
The setting time of each channel is less than 7ms. All
the sampled data is buffered in 9 dada buffers and waits
for being collected by MCU via I
data conversion encounters data overflow or saturation,
the ADFAIL bit in the status register is set to “1”. The
ADC could be powered down on three conditions: the
sleep mode, internal over temperature protection, and
UVLO=”1”. Each data buffer has a location address.
LDOs
There are two 5V LDO’s in the PT6105. One provides
the supply voltage to external MCU and internal digital
blocks. The other one provides the supply voltage to
internal analog blocks, and is also used as a bias on the
external thermal resistor.
Under no circumstance the digital LDO can be
shutdown.
I
The I
mode with the clock frequency of 100 kHz. The
interfacing block can not be turned off under any
condition.
Sleep Mode and Wake up
The MCU fully controls the PT6105’s entering and out
from sleep mode by reset and set the WKUP bit in the
configuration register. Right after power up, the
PT6105 is set initially at sleep mode. If VIN rises above
UVLO threshold and the WAKE bit set as “1”, the chip
is allowed to wake up and start to work following
commends from the MCU, after a short time delay.
At the sleep mode, digital LDO, I
register could not be powered down.
MOSFET driver control
Even though the PT6105 can not directly control the
turning on/off of two external MOSFETs, it has the
ability to power on/off the two MOSFET drivers. Two
drivers will be power down at the following conditions,
and will be powered on after these conditions disappear.
been no activity from the MCU for 2s.
2
C interface
- Sleep mode
- Internal over temperature protection
- Load protection at short circuit condition
- MCU watchdog bit is set to “1”, i.e. there has
2
C interface in the PT6105 works in the slave
Multi-cell Battery Management
Front End with I
PT6105
2
2
2
C interface, and all
C Interface
C interface. If one
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