SAF7849HL/M295,557 NXP Semiconductors, SAF7849HL/M295,557 Datasheet - Page 47

• Manufacturer Part Number: SAF7849HL/M295,557
• Description: IC AUD DECODER 144LQFP
• Manufacturer: NXP Semiconductors
• Type: Audio Decoderr

Specifications of SAF7849HL/M295,557

• Applications: Audio CD
• Voltage - Supply, Analog: 3 V ~ 3.6 V
• Voltage - Supply, Digital: 1.8V, 3.3V
• Mounting Type: Surface Mount
• Package / Case: 144-LQFP
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant, Lead free / RoHS Compliant
• Other names: 935287932557

NXP Semiconductors
SAF784X_2
Product data sheet
6.5.10.4 Operation modes
6.5.10.5 Writing, reading motor integrator value
6.5.10.6 Some notes on application motor servo
The motor controller mode is programmed in register MotorControl. It can operate open
loop, just sending a fixed power to the motor, for start-up and stopping, closed loop, or
shut-down. This register also selects between PDM and PWM formats.
Motor start and stop modes will put a fixed duty cycle PWM or fixed density PDM signal on
the motor outputs. During start or stop, motor speed can be monitored by reading
MotorIntLSB and MotorIntMSB.
MotorOv:
inside the PWM/PDM modulator block, or in the programmable gain stage. This is
signalled by the MotorOv interrupt, which can be read back on InterruptStatus2. The
interrupt clears when the overflow clears.
MotorOv can also automatically open sw1 or sw2. This is enabled by writing a ‘1’ to
bit OVFSW in register MotorControl.
It is possible to obtain the integrator value by reading the registers MotorIntLSB and
MotorIntMSB. The integrator can be written at the same location. By opening all switches,
the user can bypass the whole control and filter part, and just use the block as a DAC
towards the motor drivers. The control part can then be done by software.
The motor servo can be used to control the motor during CLV playback and also during
CAV or pseudo-CLV lock-to-disc or jump mode.
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Kf_mult operates by sampling the input. For example, for Kf_mult = 1, every sample of
the input is passed through to the integrator circuit, for a Kf_mult of 0.5, every second
sample is passed through, for a Kf_mult of 0.25, every fourth sample is passed
through, and so on.
For a DC input signal, K
the input is varying quickly, the K
not always give the same result, especially for low values of Kf_mult, where the
sampling in the extreme becomes 1 out of every 128 samples. The input samples to
the block that performs the Kf_mult multiplication occur at a rate of one sample every
24 system clock periods. Sub-sampling might affect the resulting gain.
In CLV mode, both sw1 and sw2 must be closed
In CAV/pseudo-CLV mode, sw2 must be open and sw1 can be open
The motor servo will revolve the disc at the speed corresponding to the frequency set
point. In CLV mode with lock to EFM, the frequency set point must be selected equal
to the desired readout frequency of the HF PLL
Accelerating the disc must be done in one of the start modes
Braking the disc must be done in one of the stop modes
When not setting the appropriate gains in the loop, an overflow might occur
One chip CD audio device with integrated MP3/WMA decoder
Rev. 02 — 9 May 2008
F
Kf_mult should always give the same result. If however,
F
Kf_mult combinations with the same product will
SAF784x
© NXP B.V. 2008. All rights reserved.
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