L6984 Datasheet, PDF (1/34 Pages) STMicroelectronics – 36 V 400 mA synchronous step-down switching regulator

L6984
36 V 400 mA synchronous step-down switching regulator
Datasheet - production data
VFDFPN10 4 x 4 x 1.0 mm
VDFPN10 3 x 3 x 1.0 mm
Features
 400 mA DC output current
 4.5 V to 36 V operating input voltage
 Synchronous rectification
 Low consumption mode or low noise mode
 100 µA I_Q at light load (LCM V_OUT = 3.3 V)
 13 µA I_Q-SHTDWN
 Adjustable f_SW (250 kHz - 600 kHz)
 Output voltage adjustable from 0.9 V
 No resistor divider required for 3.3 V V_OUT
 V_BIAS maximizes efficiency at light load
 350 mA valley current limit
 Constant on-time control scheme
 PGOOD open collector
 Thermal shutdown
Application
 Automotive systems (LCM)
 Battery powered applications (LCM)
 Car audio and low noise applications (LNM)
 Sensors (LNM)
 E- metering
Description
The L6984 is a step-down monolithic switching
regulator able to deliver up to 400 mA DC. The
output voltage adjustability ranges from 0.9 V. The
fixed 3.3 V V_OUT requires no external resistor
divider. The “Low Consumption Mode” (LCM) is
designed for applications active during car
parking, so it maximizes the efficiency at light load
with controlled output voltage ripple. The “Low
Noise Mode” (LNM) makes the switching
frequency almost constant over the load current
range, serving low noise application specification
like car audio/sensors. The PGOOD open
collector output can implement output voltage
sequencing during the power-up phase. The
synchronous rectification, designed for high
efficiency at medium - heavy load, and the high
switching frequency capability make the size of
the application compact. Pulse-by-pulse current
sensing on low-side power element implements
an effective constant current protection.
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Figure 1. Application schematic
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July 2014
This is information on a product in full production.
DocID025378 Rev 3
1/34
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