Rainbow Electronics MAX1499 User Manual

Page 21

MAX1497/MAX1499

3.5- and 4.5-Digit, Single-Chip ADCs with LED

Drivers and µC Interface

______________________________________________________________________________________

Default values:

8300h (for 3.5-digit, -2000)

B1E0h (for 4.5-digit, -20,000)

The underrange data register is 16-bit read/write regis-
ter (D15 is the MSB). When the conversion result falls
below the value in the underrange register, the UNDR
bit in the status register sets to 1. The LED shows a -1

followed by four dashes for the MAX1499 or a -1 fol-
lowed by three dashes for the MAX1497 (Table 4).

The data is represented in two’s complement format.

Default values: 0000h

Underrange Register (Read/Write)

MSB

LSB

D15

D14

D13

D12

D11

D10

LED Segment-Display Register 1 (Read/Write)

MSB

Bit 15

Bit 14

Bit 13

Bit 1

Bit 11

Bit 10

Bit 9

Bit 8

DP2

LSB

Bit 7

Bit 6

Bit 5

Bit 4

Bit 3

Bit 2

Bit 1

Bit 0

DP1

LED segment-display register 1 is a 16-bit read/write
register. When the LED bit (in the control register) is set
to 1, the MAX1497/MAX1499 provide direct access to
individual LED segments. The bits in the LED segment-
display register determine if a segment is on or off.
Write a zero to turn on a segment and a 1 to turn off a
segment.
DP1: Segment DP driver bit of digit 1. The default value
turns on the LED segment.
E0: Segment E driver bit of digit 0. The default value
turns on the LED segment.
F0: Segment F driver bit of digit 0. The default value
turns on the LED segment.
D0: Segment D driver bit of digit 0. The default value
turns on the LED segment.
G0: Segment G driver bit of digit 0. The default value
turns on the LED segment.
A0: Segment A driver bit of digit 0. The default value
turns on the LED segment.

C0: Segment C driver bit of digit 0. The default value
turns on the LED segment.
B0: Segment B driver bit of digit 0. The default value
turns on the LED segment.

X: Don’t care.
DP2: Segment DP driver bit of digit 2. The default value
turns on the LED segment.
E1: Segment E driver bit of digit 1. The default value
turns on the LED segment.
F1: Segment F driver bit of digit 1. The default value
turns on the LED segment.
D1: Segment D driver bit of digit 1. The default value
turns on the LED segment.
G1: Segment G driver bit of digit 1. The default value
turns on the LED segment.
A1: Segment A driver bit of digit 1. The default value
turns on the LED segment.