Data Sheet

Rev 0 7
actual battery voltage, the CHRG pin can set low, making the comparator threshold from 1.22V flip up to
1.256V (that is, increase 3% turning down threshold), To some extent to achieve a connection to the
battery's internal resistance and the resistance of the compensation. Of course, be noted that, due to user
resistance and connection resistance of the battery is ever-changing, CN1185 by adjusting the threshold
comparator flip down and can not accurately compensate for the specific circumstances of each user.
The comparator drops threshold settings come into effect four comparators.
CN1185 comparator drops threshold can fit Shanghai Consonance with the charging chip used in
conjunction. The charger has a charge status indicator pin
, with a charge-chip pull-up resistor will
pull the pin
on the power supply terminal. If the charging pin with CN1185 the CHRG pin
connected together, can achieve the state of charge threshold comparator flip down automatically
controlled.
Comparator output flash control
When CN1185 comparator suffice the following three conditions, its output will be 2 Hz flashing frequency
(blink cycle 50%).
Condition 1: CN1185 the flip threshold control input CHRG pin is low;
Condition 2: CN1185 BLINK flicker control input is high;
Condition 3: The comparator output low.
Blink comparator output controls the main function is to monitor the battery voltage application and design.
Generally used in battery charging, users want to indicate the battery voltage, but also continuously
flashing to indicate charging in progress.
Comparator hysteresis (Hysteresis) set
Comparator rising threshold is when the comparator's negative input voltage rises, the comparator output
goes low when the terminus of a high impedance state corresponding to the negative input voltage. In order
to enhance noise immunity, the rising threshold is higher than the drops threshold. Rinsing threshold and
drops threshold’s difference is the comparator hysteresis. CN1185 comparator hysteresis can HYS1 and
HYS2 two pins to set, as shown below.
HYS2 HYS1 Dropping Hysteresis Rinsing Hysteresis
0 0 Dropping threshold×1% Dropping threshold×(1+1%)
0 1 Dropping threshold×3% Dropping threshold×(1+3%)
1 0 Dropping threshold×6% Dropping threshold×(1+6%)
1 1 Dropping threshold×10% Dropping threshold×(1+10%)
Comparator hysteresis is to prevent the monitored power supply or battery voltage transient caused by the
comparator output disorder. In electronic systems, because they had been monitoring the power supply or
battery internal resistance and connection resistance, when the load suddenly changes, the voltage sense
input voltage changes suddenly which cause the comparator output change. Because in this moment, the
power supply or battery by monitoring the actual voltage does not change, so the application should be
monitored according to the load and the power supply or battery internal resistance and wiring resistance
and other factors to set the comparator hysteresis to avoid this phenomenon.
Generally, the larger the monitored power or battery internal resistance and wiring resistance , heavier load,
then the greater the hysteresis comparator to set; and conversely the opposite.
Comparator hysteresis comparator settings come into effect for four channels.
CN1185 comparator rising threshold and drops threshold will make a summary as the following table.