1FEATURES
23• Tiny 8-Bump Thin DSBGA Package: 0.84 mm ×
1.615 mm × 0.6 mm
• 2.8 V to 5.5 V Input Voltage Range
• Adjustable Output Voltage: -0.9 V to -5.5 V
• 320 mA Switch Current Limit
• 500 kHz Minimum Switching Frequency
• Ground Referred Enable Input
• Under Voltage Lock Out (UVLO)
• No External Compensation
• Internal Soft Start
• 1 μA Shutdown Supply Current
• Small Output Voltage Ripple
• WEBENCH® Enabled

APPLICATIONS
• General Purpose Negative Voltage Supply
• Negative Rail / Bias Supply For Op-amp And
Data Converters
• LCD Biasing

PERFORMANCE BENEFITS
• Easy To Use
• Tiny Overall Solution Size Reduces System
Cost

DESCRIPTION
The LMR70503 is a buck-boost converter with
adjustable negative output voltage in a tiny 8-bump
thin DSBGA package. Its unique control method is
designed to provide fast transient response, low
output noise, high efficiency, and tight regulation in
the smallest possible PCB area. The LMR70503 has
built in soft start, peak current limit, minimum
switching frequency, and Under Voltage Lock Out
(UVLO), with no external compensation required. For
ease of use, the Enable pin is referred to the IC
ground, instead of the lowest potential of the IC: the
negative output voltage.