L5964
Automotive monolithic dual step-down switching regulator with LDO
Data brief
Independent voltage supervisors/power-goods
with selectable thresholds through external pin:
– two available thresholds for UV/OV/PG
signals: 90-120-95% or 80-110-85%
(output voltage percentage)
Soft-start, thermal protection
LQFP64
(exposed pad up)
One standby/linear regulator:
– Output selectable with external resistor
divider till 10 V
– Soft start, hardware enable pin
– 250 mA maximum current capability
Features
– Standby operative mode
AEC-Q100 qualified
– Programmable power good thresholds
(85% or 95% output voltage percentage)
Two step-down synchronous switching voltage
– Thermal protection
regulators with internal power switches:
– Output voltage selectable by external
divider (feedback voltage at 0.9 V)
Microcontroller reset with programmable
duration, activated by output under voltage or
watchdog fault
– Minimum and maximum output is limited by
minimum and maximum duty cycle
External High Side Driver enable pin
– Internal high-side/ low-side NDMOS
One integrated window watchdog (5 ms ≤
– 270 kHz and 2.2 MHz selectable free-run
frequencies
window ≤ 50 ms, with ± 20% tolerance)
Short circuit protected outputs
– 125 kHz < f < 2.3 MHz synchronization
range at SYNCIN pin
Low external components number
Thermal shutdown junction temperature 150°C
– Programmable current limits at 2 A and
3.5A (> 2 A requires the addition of external
schottky diodes)
Table 1. Device summary
– Independent hardware enabling pins
– Independent supply inputs
Order code
Package
Packing
L5964L-VYY
LQFP64 exp. pad up
Tray
– 180° phase shift between outputs
– Synch out 90° phase shift vs DC-DC1
– Programmable switching frequency divider
by 1, 2, 4, 8 between the two regulators
– The two buck converters can be connected
in parallel (for evaluation purposes only)
February 2022
DB4679 Rev 1
1/16
For further information contact your local STMicroelectronics sales office.
www.st.com