SML2108 datasheet(4/21 Pages) SUMMIT

4 / 21 page

SML2108

2053 2.2 11/07/00

SUMMIT MICROELECTRONICS, Inc.

PRELIMINARY

input to the ADC using bit 5 of Register 1, the converted

value of the current entering this pin is used as the address

of the EEPROM lookup table. In this configuration the

modulation current can be controlled by temperature

rather than the bias current. Refer to the application

example on using the EXT TEMP pin. If this option is not

used the pin should be left floating.

VSSA, VSSD (13 & 14)

Analog and digital low-side supplies for on-board circuitry.

Must be at same potential as all other VSS pins.

VDD (15, 16, 21, 22, 39, 40, 45, 46, & 47)

High-side supply for the Bias and Modulation currents and

power supply input for the chip.

CE# (48)

The chip enable input is active low and provides an

additional method of enabling the serial interface. The

state of this pin has no effect on the auto-monitor function.

This pin has an internal 100k

Ω pullup.

BIASP (17, 18, 43, & 44)

High-side mean bias control current.

Current source

output range is programmable, with the optional ranges of

0 to 100mA or 0 to 10mA.

BIASN (27, 28, 33, & 34)

Low-side mean bias control current. Current sink input

range is 0 to 100mA.

MODP (19, 20, 41, &42)

High-side modulation control current. Current source

output range is programmable, with optional ranges of 0 to

100mA or 0 to 10mA.

MODN (25, 26, 35, &36)

Low-side modulation control current. Current sink input

range is 0 to 100mA.

SML2108 Datasheet(PDF) 4 Page - Summit Microelectronics, Inc.