ML4828 Micro Linear, ML4828 Datasheet

no-image

ML4828

Manufacturer Part Number
ML4828
Description
BiCMOS Phase Modulation/Soft Switching Controller
Manufacturer
Micro Linear
Datasheet

Available stocks

Company
Part Number
Manufacturer
Quantity
Price
Part Number:
ML4828CP
Manufacturer:
ML
Quantity:
1 112
Part Number:
ML4828CS
Manufacturer:
MICROLINEAR
Quantity:
20 000
Part Number:
ML4828IP
Manufacturer:
NS
Quantity:
6 219
Part Number:
ML4828IS
Quantity:
28
Part Number:
ML4828IS
Manufacturer:
ML
Quantity:
20 000
GENERAL DESCRIPTION
The ML4828 is a complete BiCMOS phase modulation
control IC suitable for full bridge soft switching converters.
Unlike conventional PWM circuits, the phase modulation
technique allows for zero voltage switching (ZVS)
transitions and square wave drive across the transformer.
The IC modulates the phases of the two sides of the bridge
to control output power.
The ML4828 can be operated in either voltage or current
mode. Both cycle-by-cycle current limit, integrating fault
detection, and soft start reset are provided. The under-
voltage lockout circuit features a 1.5V hysteresis with a
low starting current to allow off-line start up with a bleed
resistor. A shutdown function powers down the IC, putting
it into a low quiescent state.
The circuit can be operated at frequencies up to 1MHz.
The ML4828 contains four high current CMOS outputs
which feature high slew rate with low cross conduction.
BLOCK DIAGRAM
RAMP
BiCMOS Phase Modulation/Soft Switching Controller
SDN
EAO
EA+
I
EA–
RST
LIM
SS
19
10
12
20
11
7
9
8
1.25V
2.5V
1V
+
UVLO
V
14
+
CC
+
ERROR
AMP
I
LIM
IRST
ISS
2.5V REF
V
FAULT
LOGIC
REF
5
Q
Q
+
MOD
S
R
SYNC R
6
OSC
3
T
C
4
T
FEATURES
T
R
S
5V BiCMOS for low power and high frequency
(1MHz) operation
Full bridge phase modulation zero voltage switching
circuit with independent programmable delay times
Current or voltage mode operation capability
Cycle-by-cycle current limiting with integrating fault
detection and restart delay
Can be externally synchronized
Four 3 CMOS output drivers
Under-voltage lockout circuit with 1.5V hysteresis
*Some Packages Are End Of Life
Q
Q
Q
Q
GND
17
R
1
A
DELAY A
DELAY B
R
2
B
ML4828*
DRIVER
DRIVER
DRIVER
DRIVER
May 1997
16 A2
18
15 B1
13 B2
A1
1

Related parts for ML4828

ML4828 Summary of contents

Page 1

... The IC modulates the phases of the two sides of the bridge to control output power. The ML4828 can be operated in either voltage or current mode. Both cycle-by-cycle current limit, integrating fault detection, and soft start reset are provided. The under- voltage lockout circuit features a 1 ...

Page 2

... REF 2.5V reference voltage. 6 SYNC Synchronization input to oscillator Soft start capacitor connection. 8 EAO Error amplifier output. 9 EA- Error amplifier inverting input. 10 EA+ Error amplifier non-inverting input. 2 ML4828 20-Pin DIP (P20) 20-Pin SOIC (S20 LIM A SDN ...

Page 3

... Charging Current ................................................. –1mA T Junction Temperature .............................................. 150 C Storage Temperature Range ...................... – 150 C Lead Temperature (Soldering 10 sec.) ...................... 260 C Thermal Resistance ( Plastic DIP ........................................................ 67 C/W 7V Plastic SOIC ..................................................... 95 C/W OPERATING CONDITIONS + 0.3V CC Temperature Range ML4828CX ................................................. ML4828IX ............................................... – 16k , C = 270 5V CONDITIONS 4.5V < ...

Page 4

... ML4828 ELECTRICAL CHARACTERISTICS PARAMETER PHASE MODULATOR EAO Zero Duty Cycle Threshold RAMP Delay to Output RAMP Discharge Current SOFT-START Charge Current Discharge Current CURRENT LIMIT/SHUTDOWN Current Limit Threshold Pin 20 Delay to Output Pin 12 Shutdown Threshold Pin 12 Restart Threshold Pin 12 Charging Current SDN Shutdown Threshold ...

Page 5

... With both Q3 and Q4 ON, a new power cycle starts, and power is delivered to the output. The above sequence is then repeated with the roles of side A and B interchanged. should be set DB The ML4828 can also be used in current mode by sensing the load current on the RAMP input (pin 11). +VIN ...

Page 6

... The T flip-flop acts as a frequency divider ( 2), so the output frequency will be: f OSC f OUT 2 6 ERROR AMPLIFIER The ML4828 error amplifier has a 10MHz bandwidth and a 10V/ s slew rate. Figure 4 gives the Bode plot of the error amplifier. 100 – ...

Page 7

... into charging C in volts per second the next clock cycle. If the current limit condition is removed, RST will be gradually discharged to ground, and normal operation resumes as shown in Figure 6. (9) 1V V(PIN 20) (10) 2.5V V(PIN 12) ML4828 TERMINATE PWM CYCLE CLOCK INHIBIT ...

Page 8

... During start-up, the ML4828 draws very little current (typically 150 A) and V above 6.0V, the internal circuitry and V and will stay enabled until V lockout threshold. RST SHUTDOWN FUNCTION The ML4828 can be externally shut down by bringing SDN (pin 19) low. The shutdown threshold ( RST (12) For example 2.4V < ...

Page 9

... ML4828 PHYSICAL DIMENSIONS 0.498 - 0.512 (12.65 - 13.00) 20 PIN 0.024 - 0.034 0.050 BSC (0.61 - 0.86) (1.27 BSC) (4 PLACES) 0.012 - 0.020 0.090 - 0.094 (0.30 - 0.51) (2.28 - 2.39) 10 inches (millimeters) Package: S20 20-Pin SOIC 0.291 - 0.301 0.398 - 0.412 (7.39 - 7.65) (10.11 - 10.47) 0.095 - 0.107 (2.41 - 2.72) 0.005 - 0.013 SEATING PLANE (0.13 - 0.33) 0º - 8º 0.022 - 0.042 0.007 - 0.015 (0.56 - 1.07) (0.18 - 0.38) ...

Page 10

... PIN 0.060 MIN (1.52 MIN) (4 PLACES) 0.170 MAX (4.32 MAX) 0.125 MIN (3.18 MIN) inches (millimeters) (Continued) Package: P20 20-Pin PDIP 1.010 - 1.035 (25.65 - 26.29) 0.240 - 0.260 (6.09 - 6.61) 0.055 - 0.065 0.100 BSC (1.40 - 1.65) (2.54 BSC) 0.015 MIN (0.38 MIN) SEATING PLANE 0.016 - 0.022 (0.40 - 0.56) ML4828 0.295 - 0.325 (7.49 - 8.26) 0.008 - 0.012 0º - 15º (0.20 - 0.31) 11 ...

Page 11

... ORDERING INFORMATION PART NUMBER ML4828CP ML4828CS ML4828IP ML4828IS © Micro Linear 1997 is a registered trademark of Micro Linear Corporation Micro Linear Products described in this document may be covered by one or more of the following patents, U.S.: 4,897,611; 4,964,026; 5,027,116; 5,281,862; 5,283,483; 5,418,502; 5,508,570; 5,510,727; 5,523,940; 5,546,017; 5,559,470; 5,565,761; 5,592,128; 5,594,376; Japan: 2598946; 2619299. Other patents are pending. ...

Related keywords