Analog Devices AD1819B Datasheet

a
AC’97 SoundPort® Codec
AD1819B
AC’97 FEATURES Fully Compliant AC’97 Analog I/O Component 48-Terminal LQFP Package Multibit ⌺⌬ Converter Architecture for Improved
S/N Ratio >90 dB 16-Bit Stereo Full-Duplex Codec Four Analog Line-Level Stereo Inputs for Connection
from LINE, CD, VIDEO, and AUX Two Analog Line-Level Mono Inputs for Speakerphone
and PC BEEP Mono MIC Input Switchable from Two External
Sources High Quality CD Input with Ground Sense Stereo Line Level Output Mono Output for Speakerphone Power Management Support
FUNCTIONAL BLOCK DIAGRAM
AD1819B
MIC1 MIC2
LINE_IN
AUX
CD
VIDEO
PHONE_IN
LINE_OUT_L
MONO_OUT
LINE_OUT_R
PC_BEEP
0dB/ 20dB
MV
MV
MV
G A
S
M
PHAT
S
S
STEREO
S
S
A M
PHAT
S
STEREO
ENHANCED FEATURES Support for Multiple Codec Communications DSP 16-Bit Serial Port Format Variable 7 kHz to 48 kHz Sampling Rate with 1 Hz
Supports Modem Sample Rates and Filtering Phat™ Stereo 3D Stereo Enhancement VHDL and Verilog Models of Serial Port Available
G
G A M
S S
S S S S
G = GAIN A = ATTENUATE M = MUTE MV = MASTER VOLUME
G A M
G
A
A
M
M
S
S
S
Resolution
G A M
S
S
PGA
SELECTOR
PGA
G A M
G A M
CS1
CS0
MASTER/SLAVE SYNCHRONIZER
16-BIT SD A/D
CONVERTER
16-BIT
SD A/D
CONVERTER
SAMPLE
RATE
GENERATORS
16-BIT
SD D/A
CONVERTER
16-BIT
SD D/A
CONVERTER
OSCILLATORS
XTALO
CHAIN_IN
XTALI
CHAIN_CLK
RESET
SYNC
BIT_CLK
AC LINK
SDATA_OUT
SDATA_IN
SoundPort is a registered trademark of Analog Devices, Inc. Phat is a trademark of Analog Devices, Inc.
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Information furnished by Analog Devices is believed to be accurate and reliable. However, no responsibility is assumed by Analog Devices for its use, nor for any infringements of patents or other rights of third parties which may result from its use. No license is granted by implication or otherwise under any patent or patent rights of Analog Devices.
One Technology Way, P.O. Box 9106, Norwood, MA 02062-9106, U.S.A. Tel: 781/329-4700 World Wide Web Site: http://www.analog.com Fax: 781/326-8703 © Analog Devices, Inc., 1999
AD1819B
PRODUCT OVERVIEW
The AD1819B SoundPort Codec is designed to meet all require­ments of the Audio Codec ’97, Component Specification, Revision
1.03, © 1996, Intel Corporation, found at www.Intel.com. In addition, the AD1819B supports multiple codec configurations (up to three per AC-Link), a DSP serial mode, variable sample rates, modem sample rates and filtering, and built-in Phat Ste­reo 3D enhancement.
The AD1819B is an analog front end for high performance PC audio, modem, or DSP applications. The AC’97 architecture defines a 2-chip audio solution comprising a digital audio con­troller, plus a high quality analog component that includes Digital-to-Analog Converters (DACs), Analog-to-Digital Con­verters (ADCs) mixer and I/O.
The main architectural features of the AD1819B are the high
quality analog mixer section, two channels of Σ∆ ADC conver­sion, two channels of Σ∆ DAC conversion and Data Direct
Scrambling (D
2
S) rate generators. The AD1819B’s left channel ADC and DAC are compatible for modem applications support­ing irrational sample rates and modem filtering requirements.
FUNCTIONAL DESCRIPTION
This section overviews the functionality of the AD1819B and is intended as a general introduction to the capabilities of the device. Detailed reference information may be found in the descriptions of the Indexed Control Registers.
Analog Inputs
The codec contains a stereo pair of Σ∆ ADCs. Inputs to the
ADC may be selected from the following analog signals: tele­phony (PHONE_IN), mono microphone (MIC1 or MIC2), stereo line (LINE_IN), auxiliary line input (AUX), stereo CD ROM (CD), stereo audio from a video source (VIDEO) and post-mixed stereo or mono line output (LINE_OUT).
Analog Mixing
PHONE_IN, MIC1 or MIC2, LINE_IN, AUX, CD and VIDEO can be mixed in the analog domain with the stereo output from the DACs. Each channel of the stereo analog in­puts may be independently gained or attenuated from +12 dB to –34.5 dB in 1.5 dB steps. The summing path for the mono inputs (PHONE_IN, MIC1, and MIC2 to LINE_OUT) dupli­cates mono channel data on both the left and right LINE_OUT. Additionally, the PC attention signal (PC_BEEP) may be mixed with the line output. A switch allows the output of the DACs to bypass the Phat Stereo 3D enhancement.
Analog-to-Digital Signal Path
The selector sends left and right channel signals to the program­mable gain amplifier (PGA). The PGA following the selector allows independent gain for each channel entering the ADC from 0 dB to +22.5 dB in 1.5 dB steps.
Each channel of the ADC is independent, and can process left and right channel data at different sample rates. All pro­grammed sample rates from 7 kHz to 48 kHz have a resolution of 1 Hz. The AD1819B also supports irrational V.34 sample rates.
Sample Rates and D2S
The AD1819B default mode sets the codec to operate at 48 kHz sample rates. The converter pairs may process left and right channel data at different sample rates. The AD1819B sample rate generator allows the codec to instantaneously change and process sample rates from 7 kHz to 48 kHz with a resolution of 1 Hz. The in-band integrated noise and distortion artifacts in­troduced by rate conversions are below –90 dB. The AD1819B uses a 4-bit D/A structure and Data Directed Scrambling (D
2
S) to enhance noise immunity on motherboards and in PC enclo­sures, and to suppress idle tones below the device’s quantization noise floor. The D
2
S process pushes noise and distortion arti­facts caused by errors in the multibit D/A conversion process to frequencies beyond the audible range of the human ear and then filters them.
Digital-to-Analog Signal Path
The analog output of the DAC may be gained or attenuated from +12 dB to –34.5 dB in 1.5 dB steps, and summed with any of the analog input signals. The summed analog signal enters the Master Volume stage where each channel of the mixer out­put may be attenuated from 0 dB to –46.5 dB in 1.5 dB steps or muted.
Host-Based Echo Cancellation Support
The AD1819B supports time correlated I/O data format by presenting mic data on the left channel of the ADC and the mono summation of left and right output on the right channel. The ADC is splittable; left and right ADC data can be sampled at different rates.
Telephony Modem Support
The AD1819B contains a V.34-capable analog front end for supporting host-based and data pump modems. The modem DAC typical dynamic range is 90 dB over a 4.2 kHz analog output passband where F
= 12.8 kHz. The left channel of the
S
ADC and DAC may be used to convert modem data at the same sample rate in the range between 7 kHz and 48 kHz. All pro­grammed sample rates have a resolution of 1 Hz. The AD1819B supports irrational V.34 sample rates with 8/7 and 10/7 select­able sample rate multiplier coefficients.
Differences Between the AD1819A and AD1819B
The voltage reference (V
) of the AD1819B remains active
REF
while RESET is asserted. This eliminates the audible artifacts associated with the RESET LO to HI transitions that can occur during a Windows boot (power-up) or Windows warm restart (reset).
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SPECIFICATIONS
STANDARD TEST CONDITIONS UNLESS OTHERWISE NOTED
AD1819B
DAC Test Conditions
Temperature 25 °C Calibrated
Digital Supply (V Analog Supply (V Sample Rate (F
) 5.0 V 0 dB Attenuation
DD
) 5.0 V Input 0 dB
CC
) 48 kHz 10 k Output Load
S
Input Signal 1008 Hz Mute Off Analog Output Passband 20 Hz to 20 kHz
(AC-Link) 2.0 V
V
IH
(AC-Link) 0.8 V
V
IL
(CS0, CS1, CHAIN_IN) 4.0 V
V
IH
(CHAIN_CLK) 1.0 V
V
IL
ANALOG INPUT
ADC Test Conditions
Calibrated 0 dB Gain Input –3 dB Relative to Full Scale Line Input Selected
Parameter Min Typ Max Units
Input Voltage (RMS Values Assume Sine Wave Input)
LINE_IN, AUX, CD, VIDEO, PHONE_IN, PC_BEEP 1 V rms
2.83 V p-p
MIC1, MIC2 with +20 dB Gain (M20 = 1) 0.1 V rms
0.283 V p-p
MIC1, MIC2 with 0 dB Gain (M20 = 0) 1 V rms
2.83 V p-p
Input Impedance* 10 k
Input Capacitance* 15 pF
PROGRAMMABLE GAIN AMPLIFIER—ADC
Parameter Min Typ Max Units
Step Size (0 dB to 22.5 dB) 1.5 dB PGA Gain Range Span 22.5 dB
ANALOG MIXER— INPUT GAIN/AMPLIFIERS/ATTENUATORS
Parameter Min Typ Max Units
Dynamic Range (–60 dB Input THD+N, Referenced to Full Scale, A-Weighted)
CD to LINE_OUT 90 dB Other to LINE_OUT* 90 dB
Step Size (+12 dB to –34.5 dB): (All Steps Tested)
MIC, LINE_IN, AUX, CD, VIDEO, PHONE_IN, DAC 1.5 dB
Input Gain/Attenuation Range
MIC, LINE_IN, AUX, CD, VIDEO, PHONE_IN, DAC 46.5 dB
Step Size␣ (0 dB to –45 dB): (All Steps Tested)
PC_BEEP 3.0 dB
Input Gain/Attenuation Range: PC_BEEP 45 dB
DIGITAL DECIMATION AND INTERPOLATION FILTERS*
Parameter Min Typ Max Units
Passband 0 0.4 × F
Hz
S
Passband Ripple ±0.09 dB Transition Band 0.4 × F Stopband 0.6 × F
S
S
0.6 × F
Hz
S
Hz Stopband Rejection –74 dB Group Delay 12/F
S
sec
Group Delay Variation Over Passband 0.0 µs
*Guaranteed, not tested. Specifications subject to change without notice.
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AD1819B–SPECIFICATIONS
ANALOG-TO-DIGITAL CONVERTERS
Parameter Min Typ Max Units
Resolution 16 Bits Total Harmonic Distortion (THD) 0.02 %
–74 dB
Dynamic Range (–60 dB Input THD+N Referenced to Full Scale,
A-Weighted) 84 87 dB Signal-to-Intermodulation Distortion* (CCIF Method) 85 dB ADC Crosstalk*
Line Inputs (Input L, Ground R, Read R; Input R, Ground L, Read L) –100 –90 dB
Line to Other –90 –85 dB
Gain Error (Full-Scale Span Relative to Nominal Input Voltage) ±10 % Interchannel Gain Mismatch (Difference of Gain Errors) ±0.5 dB ADC Offset Error ±5mV
DIGITAL-TO-ANALOG CONVERTERS
Parameter Min Typ Max Units
Resolution 16 Bits Total Harmonic Distortion (THD) LINE_OUT 0.02 %
–74 dB
Dynamic Range (–60 dB Input THD+N Referenced to Full Scale,
A-Weighted) 85 90 dB Signal-to-Intermodulation Distortion* (CCIF Method) 85 dB
Gain Error (Full-Scale Span Relative to Nominal Input Voltage) ±10 % Interchannel Gain Mismatch (Difference of Gain Errors) ±0.5 dB
DAC Crosstalk* (Input L, Zero R, Measure LINE_OUT_R; Input R, dB
Zero L, Measure LINE_OUT_L) –80 dB
Total Out-of-Band Energy (Measured from 0.6 × F
to 20 kHz)* –40 dB
S
MASTER VOLUME
Parameter Min Typ Max Units
Step Size (0 dB to –46.5 dB)
LINE_OUT_L, LINE_OUT_R, MONO_OUT 1.5 dB Output Attenuation Range Span 46.5 dB Mute Attenuation of 0 dB Fundamental* 75 dB
ANALOG OUTPUT
Parameter Min Typ Max Units
Full-Scale Output Voltage 1 V rms
2.83 V p-p
Output Impedance* 800 External Load Impedance 10 k
Output Capacitance* 15 pF External Load Capacitance 100 pF V
REF
V
Current Drive 100 µA
REF
V
REFOUT
V
Current Drive 5mA
REFOUT
2.00 2.25 2.50 V
2.25 V
Mute Click (Muted Output Minus Unmuted Midscale DAC Output)* ±5mV
*Guaranteed, not tested. Specifications subject to change without notice.
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AD1819B
STATIC DIGITAL SPECIFICATIONS
Parameter Min Typ Max Units
High-Level Input Voltage (V Low-Level Input Voltage (V High-Level Output Voltage (V Low-Level Output Voltage (V
): Digital Inputs 0.4 × DV
IH
) 0.2 × DV
IL
), I
OH
OL
= 2 mA 0.5 × DV
OH
), I
= 2 mA 0.2 × DV
OL
DD
DD
Input Leakage Current –10 10 µA Output Leakage Current –10 10 µA
POWER SUPPLY
Parameter Min Typ Max Units
Power Supply Range—Analog 4.5 5.5 V Power Supply Range—Digital 4.5 5.5 V Power Supply Current 120 mA Power Dissipation 600 mW Analog Supply Current 60 mA Digital Supply Current 60 mA Power Supply Rejection (100 mV p-p Signal @ 1 kHz)*
(At Both Analog and Digital Supply Pins, Both ADCs and DACs) –40 dB
CLOCK SPECIFICATIONS*
Parameter Min Typ Max Units
Input Clock Frequency 24.576 MHz Recommended Clock Duty Cycle 40 50 60 %
DD
DD
V V V V
POWER-DOWN STATES
Parameter Set Bits Min Typ Max Units
ADCs and Input Mux Power-Down PR0 110 mA DACs Power-Down PR1 100 mA Analog Mixer Power-Down (V Analog Mixer Power-Down (V
REF
REF
and V
and V
On) PR1, PR2 54 mA
REFOUT
Off) PR0, PR1, PR3 47 mA
REFOUT
Digital Interface Power-Down* PR4 120 mA Internal Clocks Disabled* PR0, PR1, PR4, PR5 85 mA ADC and DAC Power-Down PR0, PR1 85 mA
Standby Mode* PR0, PR1, PR2, PR4, PR5 55 mA
V
REF
Total Power-Down PR0, PR1, PR2, PR3,
PR4, PR5 220 µA
RESET (Low) 250 µA
*Guaranteed, not tested. Specifications subject to change without notice.
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AD1819B
TIMING PARAMETERS (GUARANTEED OVER OPERATING TEMPERATURE RANGE)
Parameter Symbol Min Typ Max Units
RESET Active Low Pulsewidth t RESET Inactive to BIT_CLK Start-Up Delay t
SYNC Active High Pulsewidth t SYNC Low Pulsewidth t SYNC Inactive to BIT_CLK Start-Up Delay t
RST_LOW
RST2CLK
SYNC_HIGH
SYNC_LOW
SYNC2CLK
BIT_CLK Frequency 12.288 MHz BIT_CLK Period t
CLK_PERIOD
BIT_CLK Output Jitter* 750 ps BIT_CLK High Pulsewidth t BIT_CLK Low Pulsewidth t
CLK_HIGH
CLK_LOW
SYNC Frequency 48.0 kHz SYNC Period t Setup to Falling Edge of BIT_CLK t Hold from Falling Edge of BIT_CLK t BIT_CLK Rise Time t BIT_CLK Fall Time t SYNC Rise Time t SYNC Fall Time t SDATA_IN Rise Time t SDATA_IN Fall Time t SDATA_OUT Rise Time t SDATA_OUT Fall Time t End of Slot 2 to BIT_CLK, SDATA_IN Low t
SYNC_PERIOD
SETUP
HOLD
RISE CLK
FALL CLK
RISE SYNC
FALL SYNC
RISE DIN
FALL DIN
RISE DOUT
FALL DOUT
S2_PDOWN
Setup to Trailing Edge of RESET (Applies to
SYNC, SDATA_OUT) t
Rising Edge of RESET to HI-Z Delay t
*Output Jitter is directly dependent on crystal input jitter.
SETUP2RST
OFF
1.0 µs
162.8 ns
0.0814 1.3 µs
19.5 µs
162.8 ns
81.4 ns
32.56 40.7 48.84 ns
32.56 40.7 48.84 ns
20.8 µs
15.0 ns
15.0 ns 4ns 4ns 4ns 4ns 4ns 4ns 4ns 4ns
1.0 µs
15 ns
25 ns
RESET
BIT_CLK
SYNC
BIT_CLK
t
RST_LOW
Figure 1. Cold Reset
t
SYNC_HIGH
Figure 2. Warm Reset
BIT_CLK
SYNC
t
CLK_HIGH
Figure 3. Clock Timing
t
CLK_PERIOD
t
SYNC_HIGH
t
SYNC_PERIOD
t
RST2CLK
t
RST2CLK
t
CLK_LOW
t
SYNC_LOW
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BIT_CLK
BIT_CLK
SDATA_OUT
SYNC
SDATA_IN
SLOT 1
SLOT 2
WRITE
TO 0x26
DATA
PR4
DON’T
CARE
t
S2_PDOWN
NOTE: BIT_CLK NOT TO SCALE
RESET
SDATA_OUT
HI-Z
t
SETUP2RST
t
OFF
SDATA_IN, BIT_CLK
WARNING!
ESD SENSITIVE DEVICE
SYNC
SDATA_OUT
t
SETUP
t
HOLD
Figure 4. Data Setup and Hold
AD1819B
BIT_CLK
SYNC
SDATA_IN
SDATA_OUT
t
RISECLK
t
RISESYNC
t
RISEDIN
t
RISEDOUT
t
FALLCLK
t
FALLSYNC
t
FALLDIN
t
FALLDOUT
Figure 5. Signal Rise and Fall Time
ABSOLUTE MAXIMUM RATINGS*
Parameter Min Max Units
Power Supplies ␣ ␣ Analog (AV ␣ ␣ Digital (DV
) –0.3 6.0 V
DD
) –0.3 6.0 V
DD
Input Current (Except Supply Pins) ±10.0 mA
Analog Input Voltage (Signal Pins) –0.3 AV Digital Input Voltage (Signal Pins) –0.3 DV
+ 0.3 V
DD
+ 0.3 V
DD
Ambient Temperature (Operating) –40 +85 °C Storage Temperature –65 +150 °C
*Stresses greater than those listed under Absolute Maximum Ratings may cause
permanent damage to the device. This is a stress rating only; functional operation of the device at these or any other conditions above those indicated in the operational section of this specification is not implied. Exposure to absolute maximum rating conditions for extended periods may affect device reliability.
Figure 6. AC-Link, Link Low Power Mode Timing
Figure 7. ATE Test Mode
ORDERING GUIDE
Temperature Package Package
Model Range Description Option*
AD1819BJST –40°C to +85°C 48-Terminal LQFP ST-48
*ST = Thin Quad Flatpack.
ENVIRONMENTAL CONDITIONS
Ambient Temperature Rating
= T
T
AMB
= Case Temperature in °C
T
CASE
= Power Dissipation in W
P
D
= Thermal Resistance (Case-to-Ambient)
θ
CA
= Thermal Resistance (Junction-to-Ambient)
θ
JA
= Thermal Resistance (Junction-to-Case)
θ
JC
CASE
– (P
D
× θ
CA
)
Package
JA
LQFP 76.2°C/W 17°C/W 59.2°C/W
CAUTION
ESD (electrostatic discharge) sensitive device. Electrostatic charges as high as 4000 V readily accumulate on the human body and test equipment and can discharge without detection. Although the AD1819B features proprietary ESD protection circuitry, permanent damage may occur on devices subjected to high energy electrostatic discharges. Therefore, proper ESD precautions are recommended to avoid performance degradation or loss of functionality.
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–7–
JC
CA
AD1819B
PIN CONFIGURATION
48-Terminal LQFP
(ST-48)
DV
DD1
XTL_IN
XTL_OUT
DV
SS1
SDATA_OUT
BIT_CLK
DV
SS2
SDATA_IN
DV
DD2
SYNC
RESET
PC_BEEP
CHAIN_CLK
CHAIN_INNCCS0NCNCNCNC
CS1
48 47 46 45 44 39 38 3743 42 41 40
1
PIN 1
2
IDENTIFIER
3 4 5 6 7 8
9 10 11 12
13 14 15 16 17 18 19 20 21 22 23 24
PHONE_IN
NC = NO CONNECT
AUX_L
AUX_R
AD1819B
TOP VIEW
(Not to Scale)
CD_L
VIDEO_R
VIDEO_L
SS2
AV
CD_GND
CD_R
MIC1
DD2
AV
MIC2
LINE_IN_L
MONO_OUT
LINE_OUT_R
36 35
LINE_OUT_L CX3D
34 33
RX3D FILT_L
32 31
FILT_R AFILT2
30 29
AFILT1
28
V
REFOUT
27
V
REF
AV
26 25
AV
LINE_IN_R
SS1 DD1
PIN FUNCTION DESCRIPTIONS
Digital I/O
Pin Name LQFP I/O Description
XTL_IN 2 I 24.576 MHz Crystal or Clock Input XTL_OUT 3 O 24.576 MHz Crystal Output SDATA_OUT 5 I Serial Data Output. Serial, Time Division Multiplexed, AD1819B Input Stream BIT_CLK 6 O/I* Bit Clock Input, 12.288 MHz Serial Data Clock. Daisy Chain Output Clock SDATA_IN 8 O Serial Data Input. Serial, Time Division Multiplexed, AD1819B Output Stream SYNC 10 I 48 kHz Fixed Rate Sample Sync Clock RESET 11 I Reset. AC-Link Master Hardware Reset
*Input if the AD1819B is configured as Slave 1 or Slave 2.
Daisy Chain Connections
Pin Name LQFP I/O Description
CS0 45 I Daisy Chain Codec Select CS1 46 I Daisy Chain Codec Select CHAIN_IN 47 I Daisy Chain Data Input CHAIN_CLK 48 I/O* 24.576 MHz Buffered Clock Input/Output
*Output when configured as Master. Input when configured as Slave 1 or Slave 2.
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AD1819B
Analog I/O
These signals connect the AD1819B component to analog sources and sinks, including microphones and speakers.
Pin Name LQFP I/O Description
PC_BEEP 12 I PC Beep. PC Speaker Beep Pass-Through PHONE_IN 13 I Phone. From Telephony Subsystem Speakerphone or Handset AUX_L 14 I Auxiliary Input Left Channel AUX_R 15 I Auxiliary Input Right Channel VIDEO_L 16 I Video Audio Left Channel VIDEO_R 17 I Video Audio Right Channel CD_L 18 I CD Audio Left Channel CD_GND 19 I CD Audio Analog Ground Sense for Differential CD Input CD_R 20 I CD Audio Right Channel MIC1 21 I Microphone 1. Desktop Microphone Input MIC2 22 I Microphone 2. Second Microphone Input LINE_IN_L 23 I Line In Left Channel LINE_IN_R 24 I Line In Right Channel LINE_OUT_L 35 O Line Out Left Channel LINE_OUT_R 36 O Line Out Right Channel MONO_OUT 37 O Monaural Output to Telephony Subsystem Speakerphone
Filter/Reference
Pin Name LQFP I/O Description
V
REF
V
REFOUT
AFILT1 29 O Antialiasing Filter Capacitor—ADC Right Channel AFILT2 30 O Antialiasing Filter Capacitor—ADC Left Channel FILT_R 31 O AC-Coupling Filter Capacitor—ADC Right Channel FILT_L 32 O AC-Coupling Filter Capacitor—ADC Left Channel RX3D 33 O 3D Phat Stereo Enhancement—Capacitor CX3D 34 I 3D Phat Stereo Enhancement—Capacitor
27 O Voltage Reference Filter 28 O Voltage Reference Output 5 mA Drive (Intended for Mic Bias)
Power and Ground Signals
Pin Name LQFP I/O Description
DV
DD1
DV
SS1
DV
SS2
DV
DD2
AV
DD1
AV
SS1
AV
DD2
AV
SS2
No Connects
1 I Digital VDD—5.0 V 4 I Digital GND 7 I Digital GND 9 I Digital VDD—5.0 V 25 I Analog VDD—5.0 V 26 I Analog GND 38 I Analog VDD—5.0 V 42 I Analog GND
Pin Name LQFP I/O Description
NC 39 No Connect NC 40 No Connect NC 41 No Connect NC 43 No Connect NC 44 No Connect
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