B5973DTR STMicroelectronics

B5973D 2 A step down switching regulator for automotive applications Datasheet - production data Protection against feedback disconnection Thermal shutdown Applications HSOP8 - exposed pad Dedicated to automotive applications Description Features The B5973D is a step down monolithic power switching regulator with a minimum switch current Qualified following the AEC-Q100 limit of 2.25 A so it is able to deliver up to 2 A DC requirements (temperature Grade 1), see current to the load depending on the application PPAP for more details. conditions. The output voltage can be set from 2 A DC output current 1.235 V to 35 V. The high current level is also Operating input voltage from 4 V to 36 V achieved thanks to an HSOP8 package (i.e. SO8 package with exposed frame), that allows to 3.3 V / ( 2 %) reference voltage reduce the R down to approximately 40 th(JA) Output voltage adjustable from 1.235 V to 35 V C/W. The device uses an internal P-channel Low dropout operation: 100 % duty cycle DMOS transistor (with a typical R of 250 m ) DSon as switching element to minimize the size of the 250 kHz internally fixed frequency external components. An internal oscillator fixes Voltage feedforward the switching frequency at 250 kHz. Having a Zero load current operation minimum input voltage of 4 V only, it is particularly suitable for 5 V bus. Pulse by pulse current limit Internal current limiting with the internal frequency modulation offers an Inhibit for zero current consumption effective constant current short-circuit protection. Synchronization Figure 1. Typical application 9287 9 95() / + 9,1 9 WR 9 9&& )% 5 % 6<1& 6736 8 &203 & & ) ) 9 ,1+ *1 9 Q) 5 & &(5 0, & ) 0 December 2013 DocID14117 Rev 4 1/44 This is information on a product in full production. www.st.com S 5 & 287Contents B5973D Contents 1 Pin settings 4 1.1 Pin connection 4 1.2 Pin description 4 2 Electrical data 5 2.1 Maximum ratings 5 2.2 Thermal data . 5 3 Electrical characteristics . 6 4 Datasheet parameters over the temperature range 8 5 Functional description . 9 5.1 Power supply and voltage reference 10 5.2 Voltages monitor 10 5.3 Oscillator and synchronization . 10 5.4 Current protection . 12 5.5 Error amplifier 13 5.6 PWM comparator and power stage . 13 5.7 Inhibit function . 15 5.8 Thermal shutdown 15 6 Additional features and protection 16 6.1 Feedback disconnection 16 6.2 Output overvoltage protection . 16 6.3 Zero load . 16 7 Closing the loop . 17 7.1 Error amplifier and compensation network 18 7.2 LC filter . 19 7.3 PWM comparator . 20 2/44 DocID14117 Rev 4