AS2842 |
RFQ for AS2842 Required Field |
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| Product | Manufacturers | Pack | D/C |
| AS2842 | - | SOP-8 | - |
The AS2842 family of control ICs provide pin-for-pin replacement of the industry standard UC3842 series of devices. The devices are redesigned to provide significantly improved tolerances in power supply manufacturing. The 2.5 V reference has been trimmed to 1.0% tolerance. The oscillator discharge current is trimmed to provide guaranteed duty cycle clamping rather than specified discharge current. The circuit is more completely specified to guarantee all parameters impacting power supply manufacturing tolerances.
In addition, the oscillator and flip-flop sections have been enhanced to provide additional performance. The RT/CT pin now doubles as a synchronization input that can be easily driven from open collector/open drain logic outputs. This sync input is a high impedance input and can easily be used for externally clocked systems. The new flip-flop topology allows the duty cycle on the AS2844/5 to be guaranteed between 49 and 50%. The AS2843/5 requires less than 0.5 mA of start-up current over the full temperature range.
Features |
| • 2.5 V bandgap reference trimmed to 1.0% and temperature-compensated• Extended temperature range from - 40 to 105° C• AS2842/3 oscillations trimmed for precision duty cycle clamp• AS2844/5 have exact 50% max duty cycle clamp• Advanced oscillator design simplifies synchronization• Improved specs on UVLO and hysteresis provide more predictable start-up and shutdown• Improved 5 V regulator provides better AC noise immunity• Guaranteed performance with current sense pulled below ground• Over-temperature shutdown |
| Parameter | Symbol | Rating | Unit |
| Supply Voltage (ICC < 30 mA) | VCC | Self-Limiting | V |
| Supply Voltage (Low Impedance Source) | VCC | 30 | V |
| Output Current | IOUT | ±1 | A |
| Output Energy (Capacitive Load) | 5 | µJ | |
| Analog Inputs (Pin 2, Pin 3) | 0.3 to 30 | V | |
| Error Amp Sink Current | 10 | mA | |
| Maximum Power Dissipation 8L SOIC 8L PDIP |
PD | 750 1000 |
mW mW |
| Maximum Junction Temperature | TJ | 150 | °C |
| Storage Temperature Range | TSTG | 65 to 150 | °C |
| Lead Temperature, Soldering 10 Seconds | TL | 300 | °C |
