The SY88913 limiting post amplifier with its high gain and wide bandwidth is ideal for use as a post amplifier in fiber-optic receivers with data rates up to 1.25Gbps. Signals as small as 5mVp-p can be amplified to drive devices with PECL inputs. The SY88913 generates a chatter-free PECL Loss of Signal (/LOS). The SY88913 incorporates a programmble level detect function to identify when the input signal has been lost. This information can be fed back to the /EN input of the device to maintain stability under loss of signal conditions. Using LOSLVL pin the sensitivity of the level detect can be adjusted. The LOS LVL v oltage can be set by connecting a resistor divider between VCC and VREF, Figure 2. Figure 3 shows the relationship between input level sensitivity and the voltage set on LOSLVL. Figure 4 shows the relationship between input level sensitivity and resistor divider ratio.