XC6210 Datasheet, PDF (10/10 Pages) Torex Semiconductor – High Current, High Speed LDO Regulators

XC6210 Series
■OPERATIONAL EXPLANATION
<Output Voltage Regulator Control>
The voltage, divided by resistors R1 & R2, which are connected to the VOUT pin is compared with the internal
reference voltage by the error amplifier. The P-channel MOSFET, which is connected to the VOUT pin, is then
driven by the subsequent output signal. The output voltage at the VOUT pin is controlled & stabilized by negative
feedback. The constant current limit circuit and short circuit protection operate in relation to the level of output
current.
<Low ESR Capacitor>
With the XC6210 series regulator, a stable output voltage is achievable even if low ESR capacitors are used, as a
phase compensation circuit is built-in to the regulator. In order to ensure the effectiveness of the phase
compensation, we suggest that an output capacitor (CL) be connected as close as possible, between the output
pin (VOUT) and the VSS pin. Please use an output capacitor (CL) with a capacitance, based on the chart below.
We also suggest an input capacitor (CIN) of 1µF: this should be connected between VIN and VSS in order to
stabilize input power source.
Output Capacitor Corresponding Chart
VOUT
CL
0.8V ~ 1.45V
More Than 6.8µF
1.5V ~ 1.75V
More Than 4.7µF
1.8V ~ 5.0V
More Than 1.0µF
<Current Limiter, Short-Circuit Protection>
The XC6210 series regulator offers a combination of current limit and circuit protection by means of a built-in fixed
current limiter circuit and a foldback circuit. When the load current reaches the current limit level, the fixed
current limiter circuit operates and output voltage drops. As a result of this drop in output voltage, the foldback
circuit operates, the output voltage drops further and output current decreases. When the output pin is shorted, a
current of about 50mA flows.
<CE Pin>
The IC's internal regulator circuitry can be shut down via the signal from the CE pin with the XC6210 series. In
shutdown mode, output at the VOUT pin will be pulled down to the VSS level via R1 & R2. Options are available
for the CE pin logic (See the product classification). Note that as the XC6210B types are 'High Active / No
Pull-Down', operations will become unstable with the CE pin open. Although the CE pin is equal to an inverter
input with CMOS hysteresis, with either the pull-up or pull-down options, the CE pin input current will increase
when the IC is in operation. We suggest that you use this IC with either a VIN voltage or a VSS voltage input at the
CE pin. If this IC is used with the correct specifications for the CE pin, the IC will operate normally. However,
supply current may increase as a result of through current in the IC's internal circuitry if a voltage other than VIN or
VSS is applied.
■NOTES ON USE
1. Please use this IC within the stated absolute maximum ratings. The IC is liable to malfunction should the ratings be
exceeded.
2. Where wiring impedance is high, operations may become unstable due to noise and/or phase lag depending on
output current. Please strengthen VIN and VSS wiring in particular.
3. Please wire the input capacitor (CIN) and the output capacitor (CL) as close to the IC as possible. Should rapid
input fluctuation or load fluctuation occur, please increase the capacitor value such as CIN or CL to stabilize the
operation.
10
Data Sheet
ud200408