TC1313_09 Datasheet, PDF (1/32 Pages) Microchip Technology – 500 mA Synchronous Buck Regulator, + 300 mA LDO

TC1313
500 mA Synchronous Buck Regulator,
+ 300 mA LDO
Features
• Dual-Output Regulator (500 mA Buck Regulator
and 300 mA Low-Dropout Regulator (LDO))
• Total Device Quiescent Current = 57 µA (Typical)
• Independent Shutdown for Buck and LDO
Outputs
• Both Outputs Internally Compensated
• Synchronous Buck Regulator:
- Over 90% Typical Efficiency
- 2.0 MHz 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 = 137 mV Typical @
200 mA
- Standard Fixed-Output Voltages
(1.5V, 1.8V, 2.5V, 3.3V)
• Small 10-pin 3x3 DFN or MSOP Package Options
• Operating Junction Temperature Range:
- -40°C to +125°C
• Undervoltage Lockout (UVLO)
• Output Short Circuit Protection
• Overtemperature Protection
Applications
• Cellular Phones
• Portable Computers
• USB-Powered Devices
• Handheld Medical Instruments
• Organizers and PDAs
Description
The TC1313 device combines a 500 mA synchronous
buck regulator and 300 mA Low-Dropout Regulator
(LDO) 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 500 mA synchronous buck regulator switches at a
fixed frequency of 2.0 MHz 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 300 mA auxiliary output that
requires a single 1 µF ceramic output capacitor,
minimizing board area and cost. The typical dropout
voltage for the LDO output is 137 mV for a 200 mA
load.
The TC1313 device is available in either the 10-pin DFN
or MSOP package.
Additional protection features include: UVLO,
overtemperature and overcurrent protection on both
outputs.
For a complete listing of TC1313 standard parts,
consult your Microchip representative.
Package Type
10-Lead DFN *
SHDN2 1
10 P_GND
V_IN2 2
9 L_X
V_OUT2 3
EP
11
8 V_IN1
NC 4
7 SHDN1
A_GND 5
6 V_FB1/V_OUT1
SHDN2
V_IN2
V_OUT2
NC
A_GND
10-Lead MSOP
1
10 PGND
2
9 L_X
3
8 V_IN1
4
7 SHDN1
5
6 ^VFB1^/VOUT1
* Includes Exposed Thermal Pad (EP); see Table 3-1.
© 2009 Microchip Technology Inc.
DS21974B-page 1