A5970AD STMicroelectronics

A5970AD Up to 1 A step down-switching regulator for automotive applications Datasheet - production data Application Dedicated to automotive applications Description SO-8 The A5970AD is a step-down monolithic power switching regulator with a minimum switch current Features limit of 1.35 A so it is able to deliver up to 1 A DC current to the load depending on the application Qualified following the AEC-Q100 conditions. The output voltage can be set from requirements (see PPAP for more details) 1.235 V to V . IN 1 A DC output current The device uses an internal P-channel DMOS Operating input voltage from 4 V to 36 V transistor (with a typical R of 250 m ) as DS(on) 3.3 V / ( 2%) reference voltage switching element to minimize the size of the external components. Output voltage adjustable from 1.235 V to V IN An internal oscillator fixes the switching frequency Low dropout operation: 100% duty cycle at 500 kHz. Having a minimum input voltage of 500 kHz Internally fixed frequency 4 V only it fits the automotive applications Voltage feed-forward requiring the device operation even in cold crank conditions. Pulse by pulse current limit with the Zero load current operation internal frequency modulation offers an effective Internal current limiting constant current short-circuit protection. Inhibit for zero current consumption Synchronization Protection against feedback disconnection Thermal shutdown Figure 1. Application schematic A5970AD March 2014 DocID14661 Rev 5 1/42 This is information on a product in full production. www.st.comContents A5970AD 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 . 9 5.2 Voltages monitor 10 5.3 Oscillator and synchronization . 10 5.4 Current protection 11 5.5 Error amplifier 12 5.6 PWM comparator and power stage . 13 5.7 Inhibit function . 14 5.8 Thermal shutdown 14 6 Additional features and protection 15 6.1 Feedback disconnection 15 6.2 Output overvoltage protection . 15 6.3 Zero load . 15 7 Closing the loop . 16 7.1 Error amplifier and compensation network 17 7.2 LC filter . 18 7.3 PWM comparator . 19 2/42 DocID14661 Rev 5