DESCRIPTION (CONTINUED)

ABSOLUTE MAXIMUM RATINGS

(1)

UCC28810

UCC28811

In the critical conduction mode operation, the PWM circuit is self-oscillating with the turn-on being governed by a

transformer zero energy detector (TZE pin) and the turn-off being governed by the current sense comparator.

Additionally, the controller provides features such as peak current limit, restart timer, overvoltage protection

(OVP), and enable.

The efficient system performance is attained by incorporation of zero power detect function which allows the

controller output to shut down at light load conditions without running into overvoltage. The device also features

an innovative slew rate enhancement circuit which improves the large signal transient performance of the voltage

error amplifier. The low start-up and operating currents of the device result in low power consumption and ease

of start-up. The highly-accurate internal bandgap reference leads to tight regulation of the output voltage in

normal and OVP conditions, resulting in higher system reliability. The enable comparator ensures that the

controller is off if the feedback sense path is broken or if the input voltage is very low.

There are two key parametric differences between UCC28810 and UCC28811, the UVLO turn-on threshold and

The higher UVLO turn-on threshold of the UCC28810 allows quicker and easier start-up with a smaller VDD

capacitance while the lower UVLO turn-on threshold of UCC28811 allows operation of the critical conduction

mode controller to be easily controlled by the downstream PWM controller in two-stage power converters. The

transient response when the output is low either at start-up or during transient conditions. The UCC28811 is

suitable for applications such as street lights and larger area luminaires where a two-stage power conversion is

needed. The UCC28810 is suitable for applications such as commercial or residential retrofit luminaires where

there is no down-stream PWM conversion and the advantages of smaller VDD capacitor and improved transient

response can be realized.

Devices are available in the industrial temperature range of –40°C to 105°C. Package offering is an 8-pin SOIC

(D) package.

UVLO THRESHOLD

PIN

ORDERABLE

VOLTAGE (V)

SOURCE CURRENT

PACKAGE

SUPPLY

COUNT

DEVICE NUMBER

(

µA)

ON

OFF

Tube of 80

UCC28810D

15.8

9.7

–1300

Reel of 2500

UCC28810DR

–40°C to 105°C

D

8

Tube of 80

UCC28811D

12.5

9.7

–300

Reel of 2500

UCC28811DR

(1)

D (SOIC-8) package is available taped and reeled. Add R suffix to device type (e.g. UCC28810DR) to order quantities of 2,500 devices

per reel.

VALUE

UNIT

VDD (Internally clamped)

20

Input voltage

VSENSE, VINS, ISENSE

5

V

Minimum input

VSENSE, VINS, ISENSE

–5

voltage

VDD

30

Input current

mA

TZE

±10

Output current

GDRV

±750

mA

Output voltage

GDRV

–5

V

Storage temperature

–55 to 150

Operating temperature

–65 to 150

°C

Soldering temperature

300

(1)

Permanent device damage may occur if Absolute Maximum Ratings are exceeded. Exposure to conditions beyond the operational

limits for extended periods of time may affect device reliability. Currents are positive into, and negative out of the specified terminal.

2

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Product Folder Link(s): UCC28810 UCC28811