illustrate
The YB1210R is a series of ultra low noise, low noise output mismatch (LDO) linear voltage regulators with 2.0% voltage accuracy. When the YB1210R regulator achieves a 300mA load current of 3.3V, the 320mV low dropout output voltage range is
1.2V to 3.6V, 0.1V per level (custom voltage is considerable upon request).
The YB1210R regulator is optimized for use with low ESR and low cost ceramic capacitors, reducing the critical amount of board space in portable equipment. The YB1210R requires only a 1.0µF output capacitor and is less than 1µA in shutdown mode for stability with any load and consumption.
Built-in thermal shutdown and short-circuit protection provide safety protection against faulty operation. The YB1210R regulator is available in this SOT-23 . /SOT-25/SOT-89 package.
Typical Application Circuit Characteristics

High Precision Output Voltage: +2% Wide Output Voltage Range: 1.2~3.6V Ultra Low Noise Low Dropout Typical Output Current: 300 mA Low Quiescent Current: ~60μA 300 mA 320mV Voltage Drop at 3.3 V Output 1.0μF Ceramic Capacitor for Stability Only Input Required and output capacitor thermal protection shuts down output short circuit current limit built-in internal soft-start provides green packaging (RoHS)
application
PDA, Notebook Computer, PC Computer DSC, Mobile Phone Camera Module PCMCIA Card, PC Camera USB-based Portable Device GSM/GPRS/3G RF Transceiver Wireless LAN Bluetooth Portable Radio Battery Powered Device

Absolute Maximum Ratings Supply Voltage -0.3V to 7.0V
Output Voltage…………-0.3V to (VIN+0.3V)
Output Short Circuit Duration: Infinite Junction Temperature Range……………………+ 150 °C
Storage temperature range…………-65°C to +150°C
Lead Temperature Recommended Operating Conditions Input Supply Voltage: 2V to 6.0V
Operating temperature……………………-40℃ to +85℃
Electrostatic Discharge Sensitivity (HBM): 2kV
Electrostatic discharge sensitivity (mm) 200V thermal resistance (SOT-23/25, θjc) ...... 140℃/w
Thermal resistance (SOT-89, θjc) 46℃/w
Thermal resistance (SOT-23/25, θja)……280℃/w
Thermal resistance (SOT-89, θja)……180℃/w
Internal power consumption (SOT-23/25, PD) ...... 0.4W
Internal power consumption (SOT-89, PD) 0.55 watts

Function description
The YB1210R is an ultra-low noise, low quiescent current, low attenuation linear regulator. It is provided by SOT-23.

SOT-25/SOT-89 different packaging

application. The YB1210R can supply loads up to 300mA (typical operation, not maximum) and the output voltage is pre-set and ranges from 1.2V to 3.6V.
As shown in the functional block diagram, the YB1210R consists of reference and noise bypass circuits, error amplifiers, output drive transistors, internal feedback voltage dividers, thermal sensors and short-circuit current limiters.
The internal reference connects to the inverting input of the error amplifier. The error amplifier compares this reference to the feedback voltage and amplifies the difference. If the feedback voltage is lower than the reference voltage, the gate pass transistor is pulled low. This allows more current to pass through the output to increase the output voltage. If the feedback voltage is too high, the gate's pass transistor is pulled high, allowing less current to pass to the output.
stability
YB1210R is a high performance LDO. Stable capacitors with emphasis on low yield. It can keep stable output capacitance down to 1.0 uf. The output capacitor can also be added to optimize performance. The YB1210R will remain stable, with no load regulation, unlike many other voltage regulators.
The internal P-channel pass transistor YB1210R has low impedance characteristics.

channel MOSFET pass transistor. This design has several advantages over similar designs using PNP pass transistors, including lower operating power and longer battery life. The YB1210R only consumes 60µA of quiescent current condition. Output Short-Circuit Current Limit The YB1210R includes a current limiter that monitors the gate voltage of the pass transistor, limiting the output current to approximately 200mA for short-circuit output conditions, for example.
closure
The YB1210R also features a low-power active shutdown mode. It has a switch to turn off the device when disabled. This allows the output capacitor and load to discharge and power down the load. In shutdown mode, internal functional blocks, such as the voltage reference and error amplifier, are completely shut down and the quiescent current is less than 1 µA.
A thermal shutdown feature prevents equipment from operating in excessive temperature conditions. When the junction temperature exceeds +160°C, the thermal sensor signals the shutdown logic to turn off the pass transistor, allowing the IC to cool down. The thermal sensor turns on again after the IC turns on and the transistor junction temperature drops to +140°C. The automatic discharge circuit YB1210R deploys an NMOS connection between VOUT and ground. When the en-pin is pulled low, the NMOS is powered by the reverse signal from en. The held charge output capacitor is quickly discharged through the NMOS. It prevents the system from shutting down mode from abnormal operation in the first place.
Soft start circuit
The YB1210R includes a soft-start circuit to limit inrush current at turn-on. During power-up, the output capacitor and output load are charged with a reduced output current. Shortly after initial power-up, the soft-start function is terminated and normal operation resumes.
Application Information Enable/Disable The YB1210R comes with an active high enable to allow the regulator to be enabled. Forcing the enable pin low disables the regulator and puts it into shutdown mode. This pin cannot be left as it may lead to state.
1.0µF capacitors are recommended for input/output capacitors. Capacitors at the YB1210R input and 1.0µF output. For high regulation performance, larger input capacitor values with low ESR provide better noise rejection and line transient response. The output noise, load transient response, stability and power supply rejection are improved with large output capacitors. Low ESR ceramic capacitors provide optimum performance and space savings.