| PartNumber | ISL1220IUZ-T | ISL1221IUZ | ISL1220IUZ |
| Description | Real Time Clock REAL TIME CLKRTC IN | Real Time Clock REAL TIME CLKRTC IN | Real Time Clock REAL TIME CLKRTC IN |
| Manufacturer | Renesas Electronics | Renesas Electronics | Renesas Electronics |
| Product Category | Real Time Clock | Real Time Clock | Real Time Clock |
| RoHS | Y | Y | Y |
| Mounting Style | SMD/SMT | SMD/SMT | SMD/SMT |
| Package / Case | MSOP-10 | MSOP-10 | MSOP-10 |
| RTC Bus Interface | Serial, I2C | Serial, I2C | Serial, I2C |
| Date Format | DW:DM:M:Y | DW:DM:M:Y | DW:DM:M:Y |
| Time Format | HH:MM:SS | HH:MM:SS | HH:MM:SS |
| Battery Backup Switching | Backup Switching | Backup Switching | Backup Switching |
| RTC Memory Size | 8 B | 2 B | 8 B |
| Supply Voltage Max | 5.5 V | 5.5 V | 5.5 V |
| Supply Voltage Min | 2.7 V | 2.7 V | 2.7 V |
| Minimum Operating Temperature | - 40 C | - 40 C | - 40 C |
| Maximum Operating Temperature | + 85 C | + 85 C | + 85 C |
| Packaging | Reel | Tube | Tube |
| Function | Alarm, Calendar, Clock | Alarm, Calendar, Clock | Alarm, Calendar, Clock |
| Height | 0.95 mm (Max) | 0.95 mm (Max) | 0.95 mm |
| Length | 3.05 mm (Max) | 3.05 mm (Max) | 3.05 mm |
| Product | Real Time Clocks | Real Time Clocks | - |
| Series | ISL1220 | ISL1221 | ISL1220 |
| Width | 3.05 mm (Max) | 3.05 mm (Max) | 3.05 mm |
| Brand | Renesas / Intersil | Renesas / Intersil | Renesas / Intersil |
| Moisture Sensitive | Yes | Yes | Yes |
| Product Type | Real Time Clock | Real Time Clock | Real Time Clocks |
| Factory Pack Quantity | 2500 | 98 | 98 |
| Subcategory | Clock & Timer ICs | Clock & Timer ICs | Clock & Timer ICs |
| Unit Weight | 0.000917 oz | 0.000917 oz | 0.005051 oz |