STMicroelectronics L7987
L7987L - 61 V 3 A asynchronous step-down switching regulator with adjustable current limitation
The L7987 device is a step-down monolithic switching regulator able to deliver up to 3 A DC. The output voltage adjustability ranges from 0.8 V to VIN. The wide input voltage range and the 100% duty cycle capability meet the fail safe specifications for industrial systems. The embedded switchover feature on the VBIASpin maximizes the efficiency at light load. The adjustable current limitation, designed to select the inductor RMS current accordingly with the nominal output current, and the high switching frequency capability make the size of the application compact. Pulse-by-pulse current sensing with digital frequency foldback implements an effective constant current protection over the different application conditions. The peak current foldback decreases the stress of the power components in heavy short-circuit condition. The PGOOD open collector output can also implement output voltage sequencing during the power-up phase. Multiple devices can be synchronized sharing the SYNCH pin to prevent beating noise in low noise applications like sensors with A/D conversion.
Features
- 3 A DC output current
- 4.5 V to 61 V operating input voltage
- RDS,ON= 250 mΩ typ.
- Adjustable fSW(250 kHz - 1.5 MHz)
- Low IQ-SHD (11 μA typ. from VIN)
- Low IQ (1 mA typ. - VIN24 V - VOUT3.3 V)
- Output voltage adjustable from 0.8 V to VIN
- Synchronization
- Adjustable soft-start time
- Adjustable current limitation
- Low dropout operation (12 μs max.)
- VBIASimproves efficiency at light load
- PGOOD open collector output
- Output voltage sequencing
- Digital frequency foldback in short-circuit
- Peak current foldback in short-circuit
- Auto-recovery thermal shutdown
STEVAL-ISA152V1, 3.3 V/3 A high efficiency step down DC-DC converter (VIN= 4.5 to 60 V) based on the L7987
The STEVAL-ISA152V1 product evaluation board is a step-down switching power supply based on the L7987 regulator in an HTSSOP16 package. The output voltage can be set starting from 0.8 V. Low drop-out operation, with almost 100% duty cycle, can be achieved.
The L7987 is a 61 V, 3 A step-down asynchronous switching regulator with embedded power MOSFET caable of delivering up to 3 A of current, depending on the application conditions.
The embedded switch-over feature on the VBIAS pin and the light load management (pulse skipping) are intended to maximize power conversion efficiency across the entire load range.
The soft-start, current limit threshold and the switching frequency are adjustable for application optimization.
The device includes an internal 250 kHz oscillator that can be externally adjusted up to 1.5 MHz; two L7987 regulators can be synchronized in a 180° out-of-phase configuration for reduced total input RMS current
Features
- 3.3 V output voltage
- 3 A DC output current
- 4.5 V to 60 V input voltage
- 500 kHz switching frequency
- 3.5 ms programmed soft-start
- VBIAS switch-over for improved efficiency at light load
- 180° out of phase synchronization available
- Open drain PGOOD available
- Auto recovery overcurrent and thermal protection
- RoHS compliant
silica content library/npi/2023/stmicroelectronics-l7987
STMicroelectronics L7987 Asynchronous Switching Regulator | Avnet Silica
