TS1052CX6 RFG Taiwan Semiconductor, TS1052CX6 RFG Datasheet - Page 4

• Manufacturer Part Number: TS1052CX6 RFG
• Description: Current & Power Monitors & Regulators Constant voltage and current controller
• Manufacturer: Taiwan Semiconductor

Specifications of TS1052CX6 RFG

• Rohs: yes
• Product: Current Monitors
• Supply Voltage - Max: 18 V
• Supply Voltage - Min: 2.5 V
• Input Voltage Range: 2.5 V to 18 V

Principle of Operation and Application Hints (continues)
Current Control
The current loop is controlled via the second trans-conductance operational amplifier, the sense resistor Rsense,
and the optocoupler. The control verifies as following
Ilim is the desired limited current, Vsense is the threshold voltage for the current control loop.
As an example, with llim = 1A, Vsense = -200mV, then Rsense = 200m .
Note that the Rsense resistor should be chosen taking into account the maximum dissipation (Plim) through it
during full load operation.
As an example, with llim=1A, and Vsense=200mV, Plim=200mW.
Therefore, for most adapter and battery charger applications, a quarter-watt, or half-watt resistor to make the
current sensing function is sufficient.
Vsense threshold is achieved internally by a resistor bridge tied to the Vref voltage reference. Its middle point is
tied to the positive input of the current control operational amplifier, and its foot is to be connected to lower potential
point of the senseresistor as shown on the following figure. The resistors of this bridge are matched to provide the
best precision possible. The current siking outpits of the two trans-conductance operational amplifiers are common
(to the outpit of the IC). This makes an Oring function which ensures that whenever the current or the voltage
reaches too high values, the optocoupler is activated.
The relation between the controlled current and the controlled output voltage can be described with a square
characteristic as shown in the following V/I output-power graph
* Rsense x llim = Vsense
* Rsense = Vsense / llim
* Plim = Vsense x llim
Constant Voltage and Constant Current Controller
Output Voltage vs. Output Current
4/8
For Battery Chargers and Adaptors
TS1052
Version: A12