Internal synchronous rectification for high efficiency
Internal soft start
0.01 µA typical shutdown current
Operates from a single Li-Ion cell battery
Only three tiny surface-mount external components required (one inductor, two ceramic capacitors)
Current overload and Thermal shutdown protection
Description
The LM3673 step-down DC-DC converter is optimized for powering low voltage circuits from a single Li-Ion cell battery and
input voltage rails from 2.7V to 5.5V. It provides up to 350mA load current, over the entire input voltage range. There
are several different fixed voltage output options available as well as an adjustable output voltage version ranging from
1.1V to 3.3V.
The device offers superior features and performance for mobile phones and similar portable systems. The LM3673 uses intelligent
automatic switching between PWM and PFM for better efficiency. During PWM mode, the device operates at a fixed-frequency of
2 MHz (typ). Hysteretic PFM mode extends the battery life by reducing the quiescent current to 16 µA (typ) during light load
and standby operation. Internal synchronous rectification provides high efficiency during PWM mode operation. In shutdown
mode, the device turns off and reduces battery consumption to 0.01 µA (typ).
The LM3673 is available in a tiny 5-bump MicroSMD package in leaded (PB) and lead-free (NO PB) versions. A high switching
frequency of 2 MHz (typ) allows the use of three tiny surface-mount components, an inductor and two ceramic capacitors.
The LM3673 step-down DC-DC converter is optimized for powering low voltage circuits from a single Li-Ion cell battery and input voltage rails from 2.7V to 5.5V. It provides up to 350mA load current, over the entire input voltage range. There are several different fixed voltage output options available as well as an adjustable output voltage version ranging from 1.1V to 3.3V.
The device offers superior features and performance for mobile phones and similar portable systems. The LM3673 uses intelligent automatic switching between PWM and PFM for better efficiency. During PWM mode, the device operates at a fixed-frequency of 2 MHz (typ). Hysteretic PFM mode extends the battery life by reducing the quiescent current to 16 microA (typ) during light load and standby operation. Internal synchronous rectification provides high efficiency during PWM mode operation. In shutdown mode, the device turns off and reduces battery consumption to 0.01 micro A (typ.)
The LM3673 is available in a tiny 5-bump MicroSMD package in leaded (PB) and lead-free (NO PB) versions. A high switching frequency of 2 MHz (typ) allows the use of three tiny surface-mount components, an inductor and two ceramic capacitors.
The LM3673 evaluation board is a working demonstration of a step down DC-DC converter. The application note contains information about the evaluation board. For further information on buck converter topology, device electrical characteristics, and component selection, please refer to the datasheet.
Features:
16 microA typical quiescent current
350 mA maximum load capability
2 MHz PWM fixed switching frequency (typ)
Automatic PFM/PWM mode switching
Available in fixed and adjustable output voltages
5-bump MicroSMD package
Internal synchronous rectification for high efficiency
Internal soft start
0.01 microA typical shutdown current
Operates from a single Li-Ion cell battery
Only three tiny surface-mount external components required (one inductor, two ceramic capacitors)
The LM3673 step-down DC-DC converter is optimized for powering low voltage circuits from a single Li-Ion cell battery and input voltage rails from 2.7V to 5.5V. It provides up to 350mA load current, over the entire input voltage range. There are several different fixed voltage output options available as well as an adjustable output voltage version ranging from 1.1V to 3.3V.
The device offers superior features and performance for mobile phones and similar portable systems. The LM3673 uses intelligent automatic switching between PWM and PFM for better efficiency. During PWM mode, the device operates at a fixed-frequency of 2 MHz (typ). Hysteretic PFM mode extends the battery life by reducing the quiescent current to 16 microA (typ) during light load and standby operation. Internal synchronous rectification provides high efficiency during PWM mode operation. In shutdown mode, the device turns off and reduces battery consumption to 0.01 micro A (typ.)
The LM3673 is available in a tiny 5-bump MicroSMD package in leaded (PB) and lead-free (NO PB) versions. A high switching frequency of 2 MHz (typ) allows the use of three tiny surface-mount components, an inductor and two ceramic capacitors.
The LM3673 evaluation board is a working demonstration of a step down DC-DC converter. The application note contains information about the evaluation board. For further information on buck converter topology, device electrical characteristics, and component selection, please refer to the datasheet.
Features:
16 microA typical quiescent current
350 mA maximum load capability
2 MHz PWM fixed switching frequency (typ)
Automatic PFM/PWM mode switching
Available in fixed and adjustable output voltages
5-bump MicroSMD package
Internal synchronous rectification for high efficiency
Internal soft start
0.01 microA typical shutdown current
Operates from a single Li-Ion cell battery
Only three tiny surface-mount external components required (one inductor, two ceramic capacitors)
Current overload and Thermal shutdown protection
Applications:
Mobile phones
PDAs
MP3 players
W-LAN
Portable instruments
Digital still cameras
Portable Hard disk drives
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(CSP-9-111C1)
and Banned Substances and Materials of Interest Specification
(CSP-9-111S2)
for regulatory environmental compliance. Details may be found at:
www.national.com/en/packaging/greennopb.html.
Lead free products are RoHS compliant.
Lead Free product status is available through the search tool located
here
Note: The Early Failure Rates (EFR) were calculated as point estimate PPM based on rejects and sample size for EFR.
The Long Term Failure Rates were calculated
at 60% confidence using the Arrhenius equation at 0.7eV activation energy and derating the assumed stress
temperature of 150°C to an application temperature of 55°C.
For more information on Reliability Metrics, please click here.
