illustrate
The YB1200 series includes 150ma ultra-low noise, low loss (LDO) linear regulators designed for battery powered RF and wireless applications. The YB1200 regulator achieves a low 250mV drop load current 3.3V output at 150mA, ultra-low output 15μvrms voltage noise and psrr, and 57dB at 1kHz.
The YB1200 regulator is also optimized to use low esr and low cost ceramic capacitors to reduce board count in the critical space of handheld devices. This YB1200 requires only 0.47µF output capacitors for stability under any load.
YB1200 consumes less than 1 microamp in shutdown mode.
Other features include high output voltage accuracy and current limit protection.
The YB1200 regulator is available in miniature SC-70 /SC-82 packages.
Typical Application Circuit Features „High Accuracy +-2%„ Ultra Low Noise Low Dropout 1.8/2.5/2.6/2.8/3.0/3.3V Regulator Preset Output Stable with 0.47µF Ceramic Capacitor For Any Load Typical Output Current: 150mA Low Quiescent current: ~90µA at 150mA load (3.3V), drop 250mV only input and output capacitors needed RoHS)
application
PDA, PDA and notebook computer digital cameras, mobile phone camera modules
PCMCIA cards, PC cameras, USB-based portable devices (MP3, PMP)
GSM/GPRS/3G RF Transceiver Module Wireless LAN, Bluetooth Portable Radio

Pin configuration

Absolute Maximum Ratings Supply Voltage………..0.3V to 7.0V
Output Voltage……………………-0.3V to (VIN+0.3V)
Output Short Circuit Duration Unlimited Junction Temperature Range +150°C Storage Temperature Range …………-65°C to +150°C
Lead temperature + 250°C Thermal resistance (SC-70/82, θja) ………… 330 °C/W Internal power loss (SC-70/82, PD) ……0.3W
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

Functional block diagram

Function description
The YB1200 is an ultra-low noise, low quiescent current, low linear voltage drop regulator. Supply SC-70 and SC-82 for space and noise package sensitive applications. These devices can power loads up to 150mA.
Functional Block Diagram, YB1200
Includes reference and noise bypass circuits, error amplifier, output drive transistor, internal feedback voltage divider, thermal sensor, short circuit current limiter. Internal reference is connected to the inverting input of the wrong amplifier. This error amplifier compares this reference to the feedback voltage and amplifies the difference. If the feedback voltage is lower than the reference voltage, the pass transistor gate is pulled low. This allows more current through the output to increase the output voltage. If the feedback voltage is too high, the pass transistor gate is pulled high, allowing less current to pass to the output. Parts are provided with preset output voltages ranging from 1.8V to 3.3V.
Stability YB1200 is a high performance LDO.
Stable capacitors with emphasis on low yield. It can maintain stable output capacitance as low as 0.47uf.
The output capacitor can also be added to optimize performance. The YB1200 will remain stable, with no load regulation, unlike many other voltage regulators.
The internal P-channel pass transistor YB1200 has low impedance characteristics. P-channel MOSFET pass transistor. This one has several advantages over similar designs using PNP pass transistors, including lower operating power and longer time

Battery Life. The YB1200 only consumes 90µA of quiescent current in most cases.
Output Short Circuit Current Limit The YB1200 includes a current limiter that monitors the gate voltage of the pass transistor and limits the output current to approximately 200mA, such as in a short circuit output condition.
closure
YB1200 also has 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.
Thermal Shutdown The Thermal Shutdown feature prevents equipment from operating under 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.
Soft start circuit
The YB1200 includes a soft-start circuit to limit inrush current when turned on. Up 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 is restored.
Application Information Enable/Disable YB1200 is equipped with active high enable to allow regulator enable. 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.
The input/output capacitors are recommended to use 0.47µF capacitors on the FYB1200 input and A 0.47µF capacitor on the output. High regulation performance, large input capacitance and lower ESR provide better noise rejection and line transient response. Output noise, load transient response, stability and power supply through the use of bulk output capacitors. Low ESR ceramic capacitors provide the best performance and save space. Power supply rejection and transient PSRR and transient response can be achieved by adding input and output bypass capacitors, as well as by passive filtering techniques.