L4920

® L4920 L4921 VERY LOW DROP ADJUSTABLE REGULATORS . . . . . . . . VERY LOW DROP VOLTAGE ADJUSTABLE OUTPUT VOLTAGE FROM 1.25V TO 20V 400mA OUTPUT CURRENT LOW QUIESCENT CURRENT REVERSE VOLTAGE PROTECTION + 60/ − 60V TRANSIENT PEAK VOLTAGE PROTECTION SHORT CIRCUIT PROTECTION WITH FOLDBACK CHARACTERISTICS THERMAL SHUT-DOWN Pentaw att DESCRIPTION The L4920 and L4921 are adjustable voltage regulators with a verylow voltage drop (0.4V typ. at 0.4A Tj = 25°C), low quiescent current and comprehensive on-chip protection. Thesedevices are protectedagainst load dump and field decay transients, polarity reversal and over heating. A foldbackcurrent limiter protectsagainstload short circuits. The outputvoltage is adjustablethrough an external divider from 1.25V to 20V. The minimum operating input voltage is 5.2V (TJ = 25°C). BLOCK DIAGRAM Minidip (4 + 4) ORDERING NUMBERS : L4920 (Pentawatt) L4921 (Minidip) These regulators are designed for automotive, industrial and consumer applications where low consumption is particularly important. In battery backup and standby applications the low consumption of these devices extends battery life. June 2000 1/7 L4920/L4921 ABSOLUTE MAXIMUM RATINGS Symbol Vi Parameter DC Input Operating Voltage DC Reverse Input Voltage Transient Input Overvoltages: Load Dump: 5ms ≤ trise ≤ 10ms τf Fall time constant = 100ms R SOURCE ≥ 0.5Ω Field Decay: 5ms ≤ tfall ≤ 10ms, RSOURCE ≥ 10Ω τf Rise time constant = 33ms Value 35 Unit V TJ, TSTG Junction and Storag...