Download: PLL frequency synthesizer for tuners BU2615S / BU2615FS

Audio ICs PLL frequency synthesizer for tuners BU2615S / BU2615FS

The BU2615 PLL frequency synthesizers work up through the FM band. Featuring low radiation noise, low power con- sumption, and highly sensitive built-in RF amps, they support an IF count function. Applications Tuners (Mini components, radio cassette players, radio equipment, etc.) Features 1) Built-in high-speed prescaler can divide 5) Counter for measurement of intermediate frequen- 130MHzVCO. cies. 2) Basic oscillation of 75kHz keeps unnecessary radi- 6) Unlock detection ation noise to a low level. 7) Seven output ports (open drain). 3) Low current dissipation (during operation: 4mA, PLL The BU2614, with three output ports, is also avail- OFF: 100µA) able. 4) In addition to the standard FM and AM, also offers the 8) Serial data input (CE, CK, DA) following 7 frequencies: 25kHz, 12.5kHz, 6.25kHz, 3.125kHz, 5kHz, 3kHz, and 1kHz. Absolute maximum ratings (Ta = 25C) Recommended operating power supply voltage, Block diagram Pin assignments, Pin descriptions, Electrical characteristics (unless otherwise noted, Ta = 25C, VDD1 = VDD2 = 5.0V), Explanation of the data (1) Division data: For D0 through D15 (When S = 1, use D4 through D15.) (2) CT: Frequency measurement beginning data 1: Beginning of measurement 0: Internal counter is reset, IFIN is pulldown. (3) Output port control data: P0, P1, P2, P3, P4, P5, P6 1: Open drain output ON (P5 is LO) 0: Open drain output OFF (P5 is HI) (4) R0, R1, R2, standard frequency data (5) S: switch between FMIN and AMIN 0: FMIN 1: AMIN (6) PS: If this bit is set to ON while AMIN is selected, swallow counter division is possible. (7) CH: If this bit set to ON, output port P5 goes to phase comparison output. 0: P5 1: PD2 (8) GT: Frequency measurement time and unlock detection ON/OFF (9) TS: Test data. Input(0)., Input data format, Frequency counter (1) Structure (2) How the frequency counter operates When control data CT equals 1, the 20-bit counter and the amp go into operation. When CT equals 0, input pull- down and the counter are reset. Measuring time (gate pulse) is selected (16ms/32ms) on the basis of control data GT. When control data CT equals 0, the counter is reset. (3) Explanation of output data D0: LSB D19: MSB How the unlock detection circuit operates When control data GT equals 1, or CT equals 1, the un- lock detection circuit goes into operation for 8ms. When CT equals 1, the unlock detection circuits stops operating before the frequency counter gate pulse is emitted. When CT equals 0, or GT equals 0, the unlock detection circuit is reset. Explanation of output data, How the frequency counter and unlock detection circuit operate (1) When CT = 1: Frequency count and unlock detec- tion are carried out. (2) When CT = 0 and GT = 1: Only unlock detection is carried out. Explanation of CD terminal When frequency measurement or unlock detection is fin- ished, the CD terminal goes to LO to indicate that the count and unlock detection have finished. It also syn- chronizes with CK to output counter data. When the next data is input, it goes to HI., External dimensions (Units: mm)]

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