Siemens MGP3006X Datasheet

GHz PLL with I2C Bus and Four Chip Addresses

Features

● 1-chip system for MPU-control (I

● 4 programmable chip addresses

● Short pull-in time for quick channel switch-over

and optimized loop stability

● 2 high-current band switch outputs (20 mA)

● Software-compatible with SDA 3202 series

● Oxis III technology

Type Ordering Code Package

C Bus)

P-DSO-14-1

MGP 3006X

Bipolar IC

MGP 3006X Q67000-H5114 P-DSO-14-1 (SMD) MGP 3006X Q67006-H5114 P-DSO-14-1 Tape & Reel (SMD)

Combined with a VCO (tuner), the MGP 3006X device, with four hard-switched chip addresses, forms a digitally programmable phase-locked loop for use in television sets with PLL-frequency synthesis tuning. The PLL permits precise crystal-controlled setting of the frequency of the tuner oscillator between 16 and 1300 MHz in increments of

62.5 kHz, and, with a 2.4-GHz prescaler 1/2, in the TV-SAT band in increments of 125 kHz. The tuning process is controlled by a microprocessor via an I

C Bus noise immunity has been improved by a factor of 10 compared to the

C Bus. The

SDA 3202-2, and the new crystal oscillator generates a sinusoidal signal, suppressing the higher-order harmonics, which reduces the moiré noise considerably.

Semiconductor Group 1 04.93

MGP 3006X

Circuit Description

Tuning Section UHF/VHF The tuner signal is capacitively coupled at the UHF/VHF-input and

subsequently amplified.

REF The reference input REF should be decoupled to ground using a capacitor

of low series inductance. The signal passes through an asynchronous divider with a fixed ratio of through 32767, and is then compared in a digital frequency/phase detector to a reference frequency

Q1, Q2 This frequency is derived from a balanced, low-impedance 4-MHz crystal

oscillator (pin Q1, Q2) by dividing its output signal by The phase detector has two outputs UP and DOWN that drive the two

current sources I+ and I– of a charge pump. If the negative edge of the divided VCO-signal appears prior to the negative edge of the reference signal, the I+ current source pulses for the duration of the phase difference. In the reverse case the I– current source pulses.

P = 8, an adjustable divider with ratio N = 256

= 7.8125 kHz.

REF

Q = 512.

PD, UD If the two signals are in phase, the charge pump output (PD) goes into the

high-impedance state (PLL is locked). An active low-pass filter integrates the current pulses to generate the tuning voltage for the VCO (internal amplifier, external output transistor at UD and external RC-circuitry). The charge pump output is also switched into the high-impedance state when the control bit T0 = 1. Here it should be noted, however, that the tuning voltage can alter over a long period in the high-impedance state as a result of self-discharge in the peripheral circuitry. UD may be switched off by the control bit OS to allow external adjustments.

By means of a control bit 5I the pump current can be switched between two values by software. This programmability permits alteration of the control response of the PLL in the locked-in state. In this way different VCO-gains in the different TV-bands can be compensated, for example.

P1, P2 The software-switched outputs P1, P2 can be used for direct band

selection (20 mA current output).

P7 P7 is a general-purpose open-collector output. The test bit T1 = 1

switches the test signal Cy (divided input signal) to P7.

CAU Four different chip addresses can be set by appropriate connection of pin

CAU.

Semiconductor Group 2

MGP 3006X

I2C Bus Interface

Data are exchanged between the processor and the PLL on the I

SCL, SDA The clock is generated by the processor (input SCL), while pin SDA works

as an input or output depending on the direction of the data (open collector; external pull-up resistor). Both inputs have hysteresis and a low-pass characteristic, which enhances the noise immunity of the I Bus.

The data from the processor pass through an I

C Bus control. Depending on their function the data are subsequently stored in registers. If the bus is free, both lines will be in the marking state (SDA, SCL are high). Each telegram begins with the start condition and ends with the stop condition. Start condition: SDA goes low, while SCL remains high. Stop condition: SDA goes high while SCL remains high. All further information transfer takes place during SCL = low, and the data is forwarded to the control logic on the positive clock edge.

C Bus.

The table “bit allocation” should be referred to in the following paragraph. All telegrams are transmitted byte-by-byte, followed by a ninth clock

pulse, during which the control logic returns the SDA-line to low (acknowledge condition). The first byte is comprised of seven address bits. These are used by the processor to select the PLL from several peripheral components (chip select). The eighth bit is always low.

In the data portion of the telegram the first bit of the first or third data byte determines whether a divider ratio or control information is to follow. In each case the second byte of the same data type or a stop condition has to follow the first byte.

, GND When the supply voltage is applied a power-on reset circuit prevents the

PLL from setting the SDA-line to low, which would block the bus.

Semiconductor Group 3

MGP 3006X

Circuit Description (cont’d)

Bit Allocation

MSB A = Acknowledge

Address byte 1 1 0 0 0 MA1 MA0 0 A

Prog. divider Byte 1 0 n14 n13 n12 n11 n10 n9 n8 A

Prog. divider Byte 2 n7 n6 n5 n4 n3 n2 n1 n0 A

Control info. Byte 1 1 5I T1 T0 1 1 1 OS A

Control info. Byte 2 P7 X X X X P2 P1 X A

Divider Ratio

N = 16384 × n14 + 8192 × n13 + 4096 × n12 + 2048 × n11 + 1024 × n10 + 512 × n9 + 256 × n8 + 128 × n7 + 64 × n6 + 32 × n5 + 16 × n4 + 8 × n3 + 4 × n2 + 2 × n1 + n0

Band Selection

P1, P2, P7 = 1 Open-collector output is active.

Pump Current Programming

5I = 1 High current

UD Disable

OS = 1 UD is disabled.

Test Mode

T1, T0 = 0, 0 Normal operation T1 = 1 P7 = carry Cy of programmable divider T0 = 1 Tristate: charge pump output PD is in high-impedance state.

Semiconductor Group 4

Chip Address Switching MA1 MA0 Voltage at CAU

MGP 3006X

0 0 (0 … 0.1)

0 1 open-circuit 1 0 (0.4 … 0.6) 1 1 (0.9 … 1) V

Telegram Examples

Start-Addr-DR1-DR2-CW1-CW2-Stop Start = start condition Start-Addr-CW1-CW2-DR1-DR2-Stop Addr = address Start-Addr-DR1-DR2-CW1-Stop DR1 = divider ratio 1st byte Start-Addr-CW1-CW2-DR1-Stop DR2 = divider ratio 2nd byte Start-Addr-DR1-DR2-Stop CW1 = control word 1st Byte Start-Addr-CW1-CW2-Stop CW2 = control word 2nd Byte Start-Addr-DR1-Stop Stop = stop condition Start-Addr-CW1-Stop

Semiconductor Group 5

Pin Configuration

(top view)

MGP 3006X

Semiconductor Group 6

Pin Definitions and Functions Pin No. Symbol Function

1 PD Input active filter/charge pump output 2 Q1 Quartz crystal 3 Q2 Quartz crystal

MGP 3006X

C Bus

4 SDA Data input/output for I 5 SCL Clock input for I

6 P7 Port output (open collector) 7 CAU Address switch input 8 P2 Port output (open collector) 9 P1 Port output (open collector) 10

Supply voltage 11 UHF/VHF Signal input 12 REF Amplifier reference input 13 GND Ground 14 UD Output active filter

Semiconductor Group 7

+ 14 hidden pages