Datasheet

MAX1497/MAX1499
3.5- and 4.5-Digit, Single-Chip ADCs with LED
Drivers and µC Interface
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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 D9 D8 D7 D6 D5 D4 D3 D2 D1
D0
LED Segment-Display Register 1 (Read/Write)
MSB
Bit 15 Bit 14 Bit 13 Bit 1 Bit 11 Bit 10 Bit 9 Bit 8
A1 G1 D1 F1 E1 DP2 X B0
LSB
Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0
C0 A0 G0 D0 F0 E0 DP1 0
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.