Inside

• TI raises the bar on 3-D graphics performance with the TVP4010
• 16-bit Sigma Delta Analog Interface Circuit
• Power Distribution Devices Meet USB Specification
• Single-chip cellphone baseband power supply
• 300 mW stereo audio power amplifier offers 0.06% THD+N
• Single, high-speed MOSFET drivers in SOT=23 packages
• Wide input voltage, hign output drive CMOS op amps
• Single channel self-calibrating op amp
• Adjustable inverting DC-DC converter

Single-chip cellphone baseband power supply

Product Features

• Complete cell phone power supply system
• Three independent LDOs
• 100 mA output with 100 mV dropout
• Microprocessor reset with 250 ms delay
• 10 mA charge pump driver
• Shutdown mode: 1 ľA
• Operating temperature of -40°C to 85°C

The TPS9111 integrates a complete power supply for the baseband portion of a cellular phone handset. Power supply functions included are three programmable low-dropout regulators, a microprocessor supply monitor and reset, a charge pump and a 1.185 V bandgap reference. The high level of integration of the TPS9111 helps reduce design cycle time, lowers system costs, improves reliability and saves board space.

This device offers flexibility of design and operation that is not found in competitive products. Examples of this flexibility are seen in the operation of the three low dropout regulators. The regulators’ outputs are programmable for 3.0 V or 3.3 V and may be powered up together or enabled independently for more effective power management. All three of the regulators are rated at 100 mA. The PMOS design used in the regulators provides for very low dropout voltages of only 200 mV maximum and an operating quiescent current to only 120 ľA maximum; standby current is less than 1 ľA.

The TPS9111 also includes a microprocessor reset that generates a logic low on start up or when the output of the regulator falls below the reset trip threshold. The reset output remains in a logic low state for 250 ms after the regulated output reaches its normal range. The on-board charge pump driver may be configured as either a voltage doubler or inverter. In the inverting configuration, the charge pump can power an LCD or provide gate bias for a GaAs power amplifier. A 5-V supply for flash memory programming, or for powering the Subscriber Identity Module (SIM) in GSM applications, can be achieved using the doubler configuration and an external LDO. It is also self-protected against operation in under-voltage and over-temperature conditions.

The device has the same power supply functions as the Texas Instruments TPS9104. However, in addition to a complete baseband power supply, the TPS9104 adds amplifiers on chip, including ringer and speaker power amplifiers capable of driving 32 speakers and a low noise microphone amplifier. The TPS9111 is available in a 28-pin TSSOP package.

• TPS9111WLE