DATASHEET
ISL75051ASEH, ISL73051ASEH
FN8964
Rev.3.00
3A, Radiation Hardened, Positive, Ultra-Low Dropout Regulator
May 16, 2019
The ISL75051ASEH and ISL73051ASEH are radiation 
Features
hardened low-voltage, high-current, single-output LDOs 
DLA SMD 5962-11212
specified for up to 3.0A of continuous output current. 
 Output current up to 3.0A at T = +150C
J 
These devices operate across an input voltage range of 
2.2V to 6.0V and can provide output voltages of 0.8V to 
 Output accuracy 1.5% over MIL temperature range
5.0V adjustable, based on the resistor divider setting. 
 Ultra low dropout:
Dropout voltages as low as 65mV can be achieved using 
the device.  65mV (typical) dropout at 1.0A
The OCP pin allows the short-circuit output current limit  225mV (typical) dropout at 3.0A
threshold to be programmed by a resistor from the OCP 
 SET mitigation with no added filtering/diodes
pin to GND. The OCP setting range is 0.5A minimum to 
 Input supply range: 2.2V to 6.0V
8.5A maximum. The resistor sets the constant current 
threshold for the output under fault conditions. The 
 Fast load transient response
thermal shutdown disables the output if the device 
 Shutdown current of 10A (typical)
temperature exceeds the specified value. It subsequently 
enters an ON/OFF cycle until the fault is removed. The 
 Output adjustable using external resistors
ENABLE feature allows the part to be placed into a low 
 PSRR 66dB (typical) at 1kHz
current shutdown mode that typically draws about 10A. 
 Enable and PGood features
These devices are optimized for fast transient response and 
 Programmable soft-start/inrush current limiting
Single Event Effects (SEE). This reduces the magnitude of 
Single Event Transients (SET) seen on the output. 
 Over-temp shutdown and programmable OCP limits
Additional protection diodes and filters are not needed. 
 Stable with 47F min tantalum capacitor
These devices are stable with tantalum capacitors as low as 
47F and provide excellent regulation all the way from no 
 Radiation hardness (ISL75051ASEH only)
load to full load. Programmable soft-start allows the user 
 High dose rate (50-300rad(Si)/s): 100krad(Si)
to program the inrush current by using the decoupling 
capacitor value on the BYP pin.  Low dose rate (0.01rad(Si)/s): 50krad(Si)
 Radiation hardness (ISL73051ASEH only)
Applications
 LDO regulator for space applications  Low dose rate (0.01rad(Si)/s): 50krad(Si)
 DSP, FPGA, and P core power supplies
Related Literature
 Post-regulation of switched mode power supplies  For a full list of related documents, visit our website:
 Down-hole drilling  ISL75051ASEH, ISL73051ASEH device pages
0.30
EN
+150C
EN
BYP
ROCP
0.25
0.1F
OCP
ADJ +125C
VIN ISL75051ASEH VOUT
0.20
VIN
VOUT
R
1
PG
GND
0.15
0.1F 0.1F
220F 220F
+25C
2.67k
VIN
0.10
4.7nF
0.05
R
PG 2
0.00
0.00 0.50 1.00 1.50 2.00 2.50 3.00 3.50
100pF
I (A)
OUT
Figure 2. Dropout vs I
Figure 1. Typical Application
OUT
FN8964 Rev.3.00 Page 1 of 22
May 16, 2019
Dropout Voltage (V)ISL75051ASEH, ISL73051ASEH 
Contents
1. Overview. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.1 Block Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.2 Typical Application . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
1.3 Ordering Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.4 Pin Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.5 Pin Descriptions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
2. Specifications. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.1 Absolute Maximum Ratings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.2 Thermal Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.3 Recommended Operating Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
2.4 Radiation Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.5 Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3. Typical Operating Performance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
4. Applications Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.1 Input Voltage Requirements. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.2 Adjustable Output Voltage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.3 Input and Output Capacitor Selection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
4.4 Enable . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
4.5 Power-Good. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.6 Soft-Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
4.7 Current Limit Protection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
4.8 Thermal Guidelines . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16
5. Die and Layout Characteristics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
6. Metallization Mask Layout. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18
7. Revision History. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
8. Package Outline Drawings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
FN8964 Rev.3.00 Page 2 of 22
May 16, 2019