Features
- Qualified to Renesas Rad Hard QML-V Equivalent Screening and QCI Flow (R34TB0001EU)
- All screening and QCI are in accordance with MIL-PRF-38535 Class-V
- PVIN supply range: 3V to 18V
- Independent clock output supply: 3V to 5.5V
- Programmable output frequency starting at 25kHz
- Internal or external clock source
- Programmable phase delay as low as 15° increments
- I2C/SMBus compatible
- I2C/SMBus or pin strapping to set frequency and phase
- TID Rad Hard Assurance (RHA) testing
- LDR (≤10mrad(Si)/s): 75krad(Si)
- SEE characterization
- No DSEE for PVIN = 20.7V, VCC = 5.5V, and VCCEXT = 6.5V at 86MeV·cm²/mg
- SEFI <10µm2 at 86MeV·cm²/mg
- No missing pulse SETs and frequency deviation SETs <3.6% on CLKOUTx at 86MeV·cm²/mg
Description
The ISL74420SLH is a radiation hardened, quad-output clock fanout IC with an optional internal 48MHz oscillator, tunable by ±10% using an external resistor. It is designed to deliver synchronization clocks for space-grade and high-reliability power systems and is particularly effective in multiphase power converters, where precise clock alignment and phase control are essential for optimal current sharing and reduced EMI.
Each output can be independently programmed with a unique frequency division and phase delay, enabling fine-grained timing control across multiple power stages. For applications that require more than four outputs, multiple ISL74420SLH devices can be cascaded, supporting scalable clock distribution across complex systems.
Configuration is supported via hardware selection pins or through an I²C/SMBus interface, offering both fixed and dynamic programmability to meet a range of design needs.
The ISL74420SLH is available in a 48-lead TQFP-EP hermetic package and is fully specified across the -55°C to +125°C temperature range, making it a robust solution for timing and synchronization in space and other mission-critical environments.
Parameters
| Attributes | Value |
|---|---|
| Rating | Space |
| Cascadable? | Yes |
| Interface | I2C |
| Minimum Clock Frequency | 25kHz |
| Maximum Clock Frequency | 48MHz |
| Outputs (#) | 4 |
| Output Clock Supply Voltage (min) (V) | 3 |
| Output Clock Supply Voltage (max) (V) | 5.5 |
| Supply current (mA) | 33 |
| Supply Voltage (min) (V) | 3 - 3 |
| Supply Voltage (max) (V) | 18 - 18 |
| Temp. Range (°C) | -55 to +125°C |
| TID LDR (krad(Si)) | 75 |
| DSEE (MeV·cm2/mg) | 86 |
| Flow | RH Hermetic |
| Qualification Level | Class Ve |
| Die Sale Availability? | Yes |
| PROTO Availability? | Yes |
Package Options
| Pkg. Type | Pkg. Dimensions (mm) | Lead Count (#) | Pitch (mm) |
|---|---|---|---|
| CQFP | 10.0 x 10.0 x 0.00 | 48 | 0.6 |
Applications
- Multiphase power converters
- Synchronizing multiple converters on one board to control EMI and crosstalk
Renesas Boards & Kits
Radiation Hardened Quad Clock Output Evaluation Board
The ISL74420SLHEV1Z evaluation board is used to easily evaluate and configure the stand-alone operation of the ISL74420SLH radiation hardened, quad-output clock fanout IC.
Featuring the hermetic version of the ISL74420SLH, the ISL74420SLHEV1Z provides users with mechanical switches for... Read More
Radiation Hardened Quad Clock Output Demonstration Board
The ISL74420SLHDEMO1Z demonstration board is used to demonstrate the stand-alone operation of the ISL74420SLH radiation hardened, quad-output clock fanout IC.
Featuring the hermetic version of the ISL74420SLH, the ISL74420SLHDEMO1Z is an example of a small footprint layout with SMD resistors to... Read More
Support Communities
