Datasheet

UCC284–5, UCC284–12, UCC284–ADJ, UCC384–5, UCC384–12, UCC384–ADJ
LOW-DROPOUT 0.5-A NEGATIVE LINEAR REGULATOR
SLUS234D – JANUARY 2000 – REVISED FEBRUARY 2002
4
POST OFFICE BOX 655303 • DALLAS, TEXAS 75265
electrical characteristics T
A
= 0°C to 70°C for the UCC384 and –40°C to 85°C for the UCC284,
VIN = VOUT – 1.5 V, I
OUT
= 0 mA, C
OUT
= 4.7 µF, and CT = 0.015 µF. For UCC384–ADJ, VOUT is set
to –3.3V (unless otherwise noted)
PARAMETER TEST CONDITIONS MIN TYP MAX UNIT
UCC384–12 Fixed –12 V-0.5-A Power Supply Section (continued)
Shutdown threshold At shutdown pin (SD/CT) –1.0 –0.7 –0.4 V
Shutdown input current SD/CT = 0 V 5 10 25
µA
Output leakage in shutdown
VIN = –15 V, VOUT = 0 V,
See Note 3
1 50
µA
Overtemperature shutdown 140
°C
Overtemperature hysteresis 20
°C
UCC384–12 Fixed –12-V 0.5-A Current Limit Section
Peak current limit VOUT = 0 V 0.7 1.1 1.5 A
Overcurrent threshold 0.55 0.7 0.9 A
Current limit duty cycle VOUT = 0 V 2.5 4 %
Overcurrent time out, t
ON
VOUT = 0 V 300 500 700
µs
UCC384–ADJ Adjustable 0.5-A Regulation Section
Reference voltage
T
A
= 25°C
–1.27 –1.25 –1.23 V
Reference voltage
Over temperature –1.275 –1.215 V
Line regulation VIN = –3.5 V to –15 V, VOUT = VOUTS 0.5 3 mV
Load regulation I
OUT
= 0 mA to 0.5 A 0.1 0.18 %
Output noise voltage
BW = 10 Hz to 10 kHz, T
A
= 25°C
200
µVRMS
Dro
p
out voltage VOUT VIN
I
OUT
0.5 A, VOUT = –3.15 V 0.25 0.5 V
Dropout voltage, VOUT – VIN
I
OUT
50 mA, VOUT = –3.15 V 25 50 mV
Sense pin input current 100 250 nA
UCC384–ADJ Adjustable 0.5-A Power Supply Section
Input voltage range –15 –3.5 V
Undervoltage lockout –3.2 –2.95 –2.7 V
Quiescent current charge pump on VIN = –3.15 V, See Note 1 200 350
µA
Quiescent current VIN = –15 V 200 250
µA
Quiescent current in shutdown
VIN = –13 V, SD/CT = 0 V
T
A
= 0°C to 85°C, See Note 2
15 45
µA
Quiescent current in shutdown
VIN = –13 V, SD/CT = 0 V
T
A
= –40°C to 0°C, See Note 2
100
µA
Shutdown threshold At shutdown pin (SD/CT) –1.0 –0.7 –0.4 V
Shutdown input current SD/CT = 0V 5 10 25
µA
Output leakage in shutdown
VIN = –15V, VOUT = 0 V,
See Note 3
1 50
µA
Overtemperature shutdown 140
°C
Overtemperature hysteresis 20
°C
UCC384–ADJ Adjustable 0.5-A Current Limit Section
Peak current limit VOUT = 0 V 0.7 1.1 1.5 A
Overcurrent threshold 0.55 0.7 0.9 A
Current limit duty cycle VOUT = 0 V 2.5 4 %
Overcurrent time out, t
ON
VOUT = 0 V 300 500 700
µs
NOTES: 1. The internal charge pump is enabled only for dropout condition with low VIN. Only in this condition is the charge pump required to
provide additional output FET fate drive to maintain dropout specifications. For conditions where the charge pump is not required,
it is disabled, which lowers overall device power consumption.
2. Ensured by design. Not production tested.
3. In the application during shutdown mode, output leakage current adds to quiescent current.