ISL6551_06 Datasheet, PDF (3/26 Pages) Intersil Corporation – ZVS Full Bridge PWM Controller

ISL6551
Functional Pin Description
PACKAGE PIN #
SOIC
QFN
1
26
2
27
3
28
PIN SYMBOL
VSS
CT
RD
FUNCTION
Reference ground. All control circuits are referenced to this pin.
Set the oscillator frequency, up to 1MHz.
Adjust the clock dead time from 50ns to 1000ns.
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19, 20
21, 22
23, 24
25
26, 27
28
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16, 17
18, 19
20, 21
22
23, 24
25
R_RESDLY
Program the resonant delay from 50ns to 500ns.
R_RA
Adjust the ramp for slope compensation (from 50mV to 250mV).
ISENSE
The pin receives the current information via a current sense transformer or a power resistor.
PKILIM
Set the over current limit with the bandgap reference as the trip threshold.
BGREF
Precision bandgap reference, 1.263V ±2% overall recommended operating conditions.
R_LEB
Program the leading edge blanking from 50ns to 300ns.
CS_COMP
Set a low current sharing loop bandwidth with a capacitor.
CSS
Program the rise time and the clamping voltage with a capacitor and a resistor, respectively.
EANI
Non-inverting input of Error Amp. It is clamped by the voltage at the CSS pin (Vclamp).
EAI
Inverting input of Error Amp. It receives the feedback voltage.
EAO
Output of Error Amp. It is clamped by the voltage at the CSS pin (Vclamp).
SHARE
This pin is the SHARE BUS connecting with other unit(s) for current share operation.
LATSD
The IC is latched off with a voltage greater than 3V at this pin and is reset by recycling VDD.
DCOK
Power Good indication with a ±5% window.
ON/OFF
This is an Enable pin that controls the states of all drive signals and the soft-start.
SYNC2, SYNC1 These are the gate control signals for the output synchronous rectifiers.
LOWER2, LOWER1 Both lower drivers are PWM-controlled on the trailing edge.
UPPER2, UPPER1 Both upper drivers are driven at a fixed 50% duty cycle.
PGND
Power Ground. High current return paths for both the upper and the lower drivers.
VDDP2, VDDP1 Power is delivered to both the upper and the lower drivers through these pins.
VDD
Power is delivered to all control circuits including SYNC1 & SYNC2 via this pin.
3
FN9066.5
January 3, 2006