■DESCRIPTION
The Fujitsu MB15E05SR is a serial input Phase Locked Loop (PLL) frequency synthesizer with a 2.0 GHz prescaler. The 2.0 GHz prescaler has a dual modulus division ratio of 64/65 or 128/129 enabling pulse swallowing operation. The supply voltage range is between 2.7 V and 5.0 V. A refined charge pump supplies well-balanced output currents of 1.0 mA and 4.0 mA. The charge pump current is selectable by serial data. The phase noise of MB15E05SR was drastically improved comparing wuth the former single PLL, MB15E05SL. The data format of serial data and the pin assignments except for φP, φR and OSCout pins are same as the former one, so it is easy to replace the former one. MB15E05SR is ideally suited for the base station of GSM (Global System for Mobile Communications) and PCS.

■FEATURES
• High frequency operation: 2.0 GHz Max
• Low power supply voltage: VCC= 2.7 V to 5.0 V
• Ultra Low power supply current: ICC= 7.0 mA Typ (VCC= Vp = 3.75 V, Ta = +25°C, in locking state)
• Direct power saving function:Power supply current in power saving mode
Typ 0.1 µA (VCC= Vp = 3.75 V, Ta = +25°C)
• Dual modulus prescaler: 64/65 or 128/129
• Serial input 14-bit programmable reference divider: R = 3 to 16,383
• Serial input programmable divider consisting of:
- Binary 7-bit swallow counter: 0 to 127
- Binary 11-bit programmable counter: 3 to 2,047
• Software selectable charge pump current
• On-chip phase control for phase comparator
• Built-in digital locking detector circuit to detect PLL locking and unlocking.
• Operating temperature: Ta = –40 °C to +85 °C