TC1303A

Features:

`Dual-Output Regulator (500mA Buck Regulator and 300mA Low-Dropout Regulator)
`Power-Good Output with 300ms Delay
`Total Device Quiescent Current = 65A, Typ
`Independent Shutdown for Buck and LDO Outputs (TC1303)
`Both Outputs Internally Compensated
`Synchronous Buck Regulator:
-Over 90% Typical Efficiency
-2.0MHz Fixed-Frequency PWM (Heavy Load)
-Low Output Noise
-Automatic PWM to PFM mode transition
-Adjustable (0.8V to 4.5V) and Standard Fixed-Output Voltages (0.8V, 1.2V, 1.5V, 1.8V, 2.5V, 3.3V)
`Low-Dropout Regulator:
-Low-Dropout Voltage=137mV Typ. @ 200mA
-Standard Fixed-Output Voltages
(1.5V, 1.8V, 2.5V, 3.3V)
`Power-Good Function:
-Monitors Buck Output Function (TC1303A)
-Monitors LDO Output Function (TC1303B)
-Monitors Both Buck and LDO Output Func-tions (TC1303C and TC1304)
-300ms Delay Used for Processor Reset
`Sequenced Startup and Shutdown (TC1304)
`Small 10-pin 3X3 DFN or MSOP Package Options
`Operating Junction Temperature Range:
--40 to +125
`Undervoltage Lockout (UVLO)
`Output Short Circuit Protection
`Overtemperature Protection

Application

·Cellular Phones
·Portable Computers
·USB-Powered Devices
·Handheld Medical Instruments
·Organizers and PDAs




Specifications

Parameter NameValueDevice DescriptionLin Reg and Power Mgt CombinationSW Reg OutputFixed or AdjsutableTypical Active Supply (A)38Switching Frequency (kHz)2000Output Current (mA)500Output Voltage (V)0.8 to 4.5Input Voltage Range (V)2.7 to 5.5

Parameter Name	Value
Device Description	Lin Reg and Power Mgt Combination
SW Reg Output	Fixed or Adjsutable
Typical Active Supply (A)	38
Switching Frequency (kHz)	2000
Output Current (mA)	500
Output Voltage (V)	0.8 to 4.5
Input Voltage Range (V)	2.7 to 5.5

Absolute Maximum Ratings
V_IN - A_GND .....................................................................6.0V
All Other I/O................................(A_GND- 0.3V)to (V_IN + 0.3V)
L_X to P_GND............................................-0.3V to (V_IN + 0.3V)
P_GND to A_GND...................................................-0.3V to +0.3V
Output Short Circuit Current ...............................Continuous
Power Dissipation (Note7)..........................Internally Limited
Storage temperature.....................................-65 to +150
Ambient Temp. with Power Applied.................-40 to +85
Operating Junction Temperature...................-40 to +125
ESD protection on all pins (HBM)..................................... 3kV

Notice: Stresses above those listed under 'Maximu Ratings' may cause permanent damage to the device. This i a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operational listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability.

Description

The TC1303A combines a 500mA synchronous buck regulator and a 300mA low-dropout (LDO) regulator with a power-good monitor to provide a highly integrated solution for applications that require multiple supply voltages. The power-good function monitors the output of the buck regulator.

The TC1303A/TC1304 combines a 500mA synchro- nous buck regulator and 300mA Low-Dropout Regula- tor (LDO) with a power-good monitor to provide a highly integrated solution for devices that require multiple supply voltages. The unique combination of an integrated buck switching regulator and low-dropout linear regulator provides the lowest system cost for dual-output voltage applications that require one lower processor core voltage and one higher bias voltage.

The 500mA synchronous buck regulator switches at a fixed frequency of 2.0MHz when the load is heavy, providing a low noise, small-size solution. When the load on the buck output is reduced to light levels, it changes operation to a Pulse Frequency Modulation (PFM) mode to minimize quiescent current draw from the battery. No intervention is necessary for smooth transition from one mode to another.

The LDO provides a 300mA auxiliary output that requires a single 1|ìF ceramic output capacitor minimizing board area and cost. The typical dropout voltage for the LDO output is 137mV for a 200mA load.

For the TC1303A/TC1304, the power-good output is based on the regulation of the buck regulator output, the LDO output or the combination of both. The TC1304 features start-up and shutdown output sequencing. The TC1303A/TC1304 is available in either the 10-pin DFN or MSOP package.

Additional protection features include: UVLO, overtemperature and overcurrent protection on bothoutputs.

For a complete listing of TC1303A/TC1304 standard parts, consult your Microchip representative.