Datasheet

VSP3200, 3210
13
SBMS012A
other system circuits, as it would affect the reference
voltage of the A/D converter and prevent proper A/D
conversion.
• External Reference: to set the external reference mode,
D2 of the configuration register must be set to “1”. In
external reference mode, V
REF
operates as an analog
voltage input pin. Inputting half the voltage necessary for
the full-scale voltage range (e.g.: 1.7V applied for a
necessary 3.4Vp-p input range), with a reference voltage
range from 0.25V to 1.75V, will create the full-scale
range. Thus, when V
REF
is 0.5V, the full-scale range will
be 0.5Vp-p, and when V
REF
is 1.75V, the full-scale range
will be 3.5Vp-p.
PROGRAMMING THE VSP3200 AND VSP3210
The VSP3200 and VSP3210 consist of three CCD channels
and a 16-bit A/D. Each channel (Red, Green, and Blue) has
its own 10-bit Offset and 6-bit Gain Adjustable Registers to
be programmed by the user. There is also an 8-bit Configu-
ration Register, on-chip, to program the different operation
modes. Those registers are shown in Table III.
CONFIGURATION REGISTER
The Configuration Register design is shown in Table V.
These registers can be accessed by the following two pro-
gramming modes:
• Parallel Programming Mode (VSP3200 only) using digi-
tal data output pins, with the data bus assigned as D0 to
D9 (pins 25 to 34), and the address bus as A0 to A2 (pins
35 to 37). It can be used for both reading and writing
operations. However, it cannot be used by the
Demultiplexed mode (when D7 of the Configuration
Register is set to “1”).
• Serial Programming Mode using a serial port, Serial Data
(SD), the Serial Shift Clock (SCLK), and Write Signal
(WRT) assigned.
It can be used only for writing operations; reading opera-
tions via the serial port are prohibited.
Table IV shows how to access these modes (VSP3200 only).
OE P/S MODE
0 0 Digital data output enabled, Serial mode enabled
0 1 Prohibit mode (can not set this mode)
1 0 Digital data output disabled, Serial mode enabled
1 1 Digital data output disabled, Parallel mode enabled
TABLE IV. Access Mode for Serial and Parallel Port
(VSP3200 Only).
BIT LOGIC ‘0’ LOGIC ‘1’
D0 CCD mode CIS mode
D1 V
REF
= 1V V
REF
=1.5V
D2 Internal Reference External Reference
D3 3-channel Mode, 1-channel Mode,
D4 and D5 disabled D4 and D5 enabled
D4, D5 (disabled when 3-channel) D4 D5
00
1-channel mode, Red channel
01 1-channel mode, Green channel
10 1-channel mode, Blue channel
D6 MUX Sequence MUX Sequence
Red > Green > Blue Blue > Green >Red
D7
(1)
Normal output mode Demultiplexed output mode
TABLE V. Configuration Register Design.
Power-on default value is all “0s”, set to 3-Channel CCD
mode with 1V internal reference, R > G > B MUX sequence,
and normal output mode.
For reading/writing to the Configuration Register, the ad-
dress will be A2 = “0”, A1 = “0”, and A0 = “0”.
For Example:
A 3-Channel CCD with internal reference V
REF
= 1V (2V
full-scale input), R > G > B sequence and normal output
mode will be D0 = “0”, D1 = “0”, D2 =“0”, D3 = “0”,
D4 = “x (don’t care)”, D5 = “x (don’t care)”, D6 = “0”, and
D7 = “0”.
For this example, bypass V
REF
with an appropriate capacitor
(e.g.:, 10µF to 0.1µF) when internal reference mode is used.
Another Example:
A 1-Channel CCD mode (Green channel) with an external
1.2V reference (2.4V full-scale input), Demultiplexed Out-
put mode will be D0 = “0”, D1 = “x (don’t care)”, D2 = “1”,
D3 = “1”, D4 = “0”, D5 = “1”, D6 = “x (don’t care)”, and
D7 = “1”.
For this example, V
REF
will be an input pin applied with 1.2V.
TABLE III. On-Chip Registers.
ADDRESS POWER-ON
A2 A1 A0 REGISTER DEFAULT VALUE
0 0 0 Configuration Register (8-bit) All “0s”
0 0 1 Red Channel Offset Register (10-bit) All “0s”
0 1 0 Green Channel Offset Register (10-bit) All “0s”
0 1 1 Blue Channel Offset Register (10-bit) All “0s”
1 0 0 Red Channel Gain Register (6-bit) All “0s”
1 0 1 Green Channel Gain Register (6-bit) All “0s”
1 1 0 Blue Channel Gain Register (6-bit) All “0s”
1 1 1 Reserved
NOTE: (1) D7 of the configuration register should always be set to “1” for the
VSP3210. Power-on default value is “0”; initial write operation for “1” is also
needed for the VSP3210, when in power-on.
Not Recommended for New Designs