Rainbow Electronics MAX5090C User Manual

General Description
The MAX5090A/B/C easy-to-use, high-efficiency, high­voltage step-down DC-DC converters operate from an input voltage up to 76V, and consume only 310µA qui­escent current at no load. This pulse-width-modulated (PWM) converter operates at a fixed 127kHz switching frequency at heavy loads, and automatically switches to pulse-skipping mode to provide low quiescent cur­rent and high efficiency at light loads. The MAX5090 includes internal frequency compensation simplifying circuit implementation. The device can also be syn­chronized with external system clock frequency in a noise-sensitive application. The MAX5090 uses an internal low on-resistance and a high-voltage DMOS transistor to obtain high efficiency and reduce overall system cost. This device includes undervoltage lock­out, cycle-by-cycle current limit, hiccup-mode output short-circuit protection, and overtemperature shutdown.
The MAX5090 delivers up to 2A output current. External shutdown is included, featuring 19µA (typ) shutdown current. The MAX5090A/MAX5090B versions have fixed output voltages of 3.3V and 5V, respectively, while the MAX5090C features an adjustable 1.265V to 11V output voltage.
The MAX5090 is available in a space-saving 16-pin thin QFN package (5mm x 5mm) and operates over the automotive temperature range (-40°C to +125°C).
Applications
Automotive
Industrial
Distributed Power
Features
Wide Input Voltage Range: 6.5V to 76V
Fixed (3.3V, 5V) and Adjustable (1.265V to 11V)
Output-Voltage Versions
2A Output Current
Efficiency Up to 92%Internal 0.26High-Side DMOS FET
310µA Quiescent Current at No Load
19µA Shutdown Current
Internal Frequency Compensation
Fixed 127kHz Switching Frequency
External Frequency Synchronization
Thermal Shutdown and Short-Circuit Current Limit
-40°C to +125°C Automotive Temperature Range
16-Pin (5mm x 5mm) Thin QFN Package
Capable of Dissipating 2.67W at +70°C
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down
DC-DC Converters
________________________________________________________________ Maxim Integrated Products 1
15
16
14
13
6
5
7
LX
V
IN
8
LX
N.C.
ON/OFF
PGND
12
DRAIN
4
12EP11 9
N.C.
N.C.
FB
SS
SYNC
VD
MA5090
BST SGND
3
10
DRAIN
TQFN
TOP VIEW
Pin Configuration
PGND
BST
LX
V
IN
SGND
FB
V
OUT
5V/2A
VD
100µH
C
BST
0.22µF
3.3µF
ON/OFF
C
OUT
100µF
SS
SYNC
D1 PDS5100H
DRAIN
C
SS
0.047µF
C
IN
68µF
C
BYPASS
0.47µF
R
IN
10
V
IN
7.5V TO 76V
MAX5090B
Typical Operating Circuit
19-3872; Rev 0; 3/06
For pricing, delivery, and ordering information, please contact Maxim/Dallas Direct! at 1-888-629-4642, or visit Maxim’s website at www.maxim-ic.com.
PART
TEMP
RANGE
PIN­PACKAGE*
OUTPUT
VOLTAGE
(V)
MAX5090AATE+
3.3
MAX5090AATE
3.3
MAX5090BATE+
5.0
MAX5090BATE
5.0
Ordering Information
Ordering Information continued at end of data sheet.
*The package code is T1655-3. **EP = Exposed pad. +Denotes lead-free package.
-40°C to +125°C 16 TQFN-EP**
-40°C to +125°C 16 TQFN-EP**
-40°C to +125°C 16 TQFN-EP**
-40°C to +125°C 16 TQFN-EP**
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters
2 _______________________________________________________________________________________
ABSOLUTE MAXIMUM RATINGS
Stresses beyond those listed under "Absolute Maximum Ratings" may cause damage to the device. These are stress ratings only, and functional operation of the device at these or any other conditions beyond those indicated in the operational sections of the specifications is not implied. Exposure to absolute maxi­mum rating conditions for extended periods may affect device reliability.
(Voltages referenced to PGND, unless otherwise specified.) V
IN
, DRAIN .............................................................-0.3V to +80V
SGND, PGND.………………………………………-0.3V to +0.3V
LX.................................................................-0.8V to (V
IN
+ 0.3V)
BST ...............................................................-0.3V to (V
IN
+ 10V)
BST to LX................................................................-0.3V to +10V
ON/
OFF........................................................-0.3V to (VIN+ 0.3V)
VD, SYNC ...............................................................-0.3V to +12V
SS…………………………………………………………-0.3 to +4V FB
MAX5090A/MAX5090B…………….……… ...….-0.3V to +15V
MAX5090C ................1mA (internally clamped to +2V, -0.3V)
V
OUT
Short-Circuit Duration………………………… ...Continuous
VD Short-Circuit Duration………….............................Continuous
Continuous Power Dissipation (TA= +70°C)*
16-Pin TQFN (derate 33.3mW/°C above +70°C) ........2.667W
Operating Junction Temperature Range...........-40°C to +125°C
Storage Temperature Range .........................…-65°C to +150°C
Junction Temperature……...……………………………….+150°C
Lead Temperature (soldering, 10s) .................................+300°C
ELECTRICAL CHARACTERISTICS
(VIN= +12V, V
ON/OFF
= +12V, V
SYNC
= 0V, I
OUT
= 0, TA= TJ= -40°C to +125°C, unless otherwise noted. Typical values are at
T
A
= +25°C. See the Typical Operating Circuit.) (Note 1)
*As per JEDEC 51 Standard Multilayer Board.
PARAMETER
CONDITIONS
UNITS
Input Voltage Range V
IN
6.5
V
Undervoltage Lockout UVLO VIN rising
V
UVLO Hysteresis
0.5 V
VIN = 6.5V to 76V, I
OUT
= 0 to 2A
3.3
VIN = 7.5V to 76V, I
OUT
= 0 to 2A
5.0
Output Voltage V
OUT
VIN = 7V to 76V, I
OUT
= 0 to 1A
5.0
V
Output Voltage Range V
OUT
MAX5090C only
V
Feedback Voltage V
FB
MAX5090C, VIN = 6.5V to 76V
V
VIN = 12V, I
OUT
= 1A 80
VIN = 12V, I
OUT
= 1A 88Efficiency η
VIN = 12V, V
OUT
= 5V, I
OUT
= 1A 88
%
VIN = 6.5V to 28V 310
VIN = 7V to 28V 310
Quiescent Supply Current
(Note 2)
I
Q
VIN = 6.5V to 28V 310
µA
VIN = 6.5V to 40V 310
VIN = 7V to 40V 310
Quiescent Supply Current
(Note 2)
I
Q
VIN = 6.5V to 40V 310
µA
VIN = 6.5V to 76V 310
VIN = 7V to 76V 310
Quiescent Supply Current (Note 2)
I
Q
VIN = 6.5V to 76V 310
µA
Shutdown Current I
SHDN
V
ON/OFF
= 0V, VIN = 14V 19 45 µA
SOFT-START
Default Internal Soft-Start Period
C
SS
= 0 700 µs
Soft-Start Charge Current
I
SS
4.5 10
µA
SYMBOL
UVLO
HYS
MIN TYP MAX
5.70 6.17 6.45
MAX5090A
MAX5090B
MAX5090B
MAX5090A
MAX5090B
MAX5090C
MAX5090A
MAX5090B
MAX5090C
MAX5090A
MAX5090B
MAX5090C
MAX5090A
MAX5090B
MAX5090C
3.20
4.85
4.85
1.265 11.000
1.191 1.228 1.265
76.0
3.39
5.15
5.15
550
550
550
570
570
570
650
650
650
16.0
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down
DC-DC Converters
_______________________________________________________________________________________ 3
ELECTRICAL CHARACTERISTICS (continued)
(VIN= +12V, V
ON/OFF
= +12V, V
SYNC
= 0V, I
OUT
= 0, TA= TJ= -40°C to +125°C, unless otherwise noted. Typical values are at
T
A
= +25°C. See the Typical Operating Circuit.) (Note 1)
PARAMETER
SYMBOL
CONDITIONS
MIN
TYP
MAX
UNITS
Soft-Start Reference Voltage
)
V
INTERNAL SWITCH/CURRENT LIMIT
Peak Switch Current Limit I
LIM
(Note 3) 2.4 3.3 5.0 A
Switch Leakage Current I
OL
VIN = 76V, V
ON/OFF
= 0V, VLX = 0V -10
µA
Switch On-Resistance
)
I
SWITCH
= 1A
0.4
PFM Threshold I
PFM
Minimum switch current in any cycle 1 60
mA
PFM Threshold I
PFM
Minimum switch current in any cycle at TJ +25°C (Note 4)
14
mA
FB Input Bias Current I
B
MAX5090C, VFB = 1.2V
nA
ON/OFF CONTROL INPUT
ON/OFF Input-Voltage Threshold
Rising trip point
V
ON/OFF Input-Voltage Hysteresis
V
HYST
100 mV
ON/OFF Input Current
V
ON/OFF
= 0V to V
IN
10
nA
OSCILLATOR/SYNCHRONIZATION
Oscillator Frequency f
0SC
106
kHz
Synchronization f
SYNC
kHz
Maximum Duty Cycle D
MAX
VIN = 6.5V to 76V, V
OUT
11V 80 95 %
SYNC High-Level Voltage 2.0 V
SYNC Low-Level Voltage 0.8 V
SYNC Minimum Pulse Width
ns
SYNC Input Leakage -1 +1 µA
INTERNAL VOLTAGE REGULATOR
Regulator Output Voltage VD VIN = 9V to 76V, I
OUT
= 0 7.0 7.8 8.4 V
Dropout Voltage 6.5V VIN 8.5V, I
OUT
= 15mA 0.5 V
Load Regulation
0 to 15mA 10
PACKAGE THERMAL CHARACTERISTICS
Thermal Resistance (Junction to Ambient)
θ
JA
TQFN package (JEDEC 51) 30
°C/W
THERMAL SHUTDOWN
Thermal-Shutdown Junction Temperature
T
SH
Temperature rising
°C
Thermal-Shutdown Hysteresis
T
HYST
20 °C
Note 1: All limits at -40°C are guaranteed by design, not production tested. Note 2: For total current consumption during switching (at no load), also see the Typical Operating Characteristics. Note 3: Switch current at which the current-limit circuit is activated. Note 4: Limits are guaranteed by design.
V
SS(REF
R
DS(ON
V
ON/OFF
I
ON/OFF
VD/I
VD
1.23 1.46 1.65
0.26
-150 +0.1 +150
1.180 1.38 1.546
127 150
119 200
+175
+10
300
300
100
350
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters
4 _______________________________________________________________________________________
Typical Operating Characteristics
(VIN= 12V, V
ON/OFF
=12V, TA= TJ= -40°C to +125°C, unless otherwise noted. Typical values are at TA= +25°C. See the Typical
Operating Circuit, if applicable.)
3.20
3.24
3.22
3.28
3.26
3.32
3.30
3.34
3.38
3.36
3.40
-50 0 25-25 50 75 100 125 150
V
OUT
vs. TEMPERATURE
(MAX5090AATE, V
OUT
= 3.3V)
MAX5090 toc01
AMBIENT TEMPERATURE (°C)
V
OUT
(V)
I
OUT
= 0
I
OUT
= 2A
4.85
4.90
4.95
5.00
5.05
5.10
5.15
-50 0-25 25 50 75 100 125 150
V
OUT
vs. TEMPERATURE
(MAX5090BATE, V
OUT
= 5V)
MAX5090 toc02
AMBIENT TEMPERATURE (°C)
V
OUT
(V)
I
OUT
= 0
I
OUT
= 2
3.20
3.26
3.24
3.22
3.30
3.28
3.38
3.36
3.34
3.32
3.40
6.5 16 26 36 46 56 66 76
LINE REGULATION
(MAX5090AATE, V
OUT
= 3.3V)
MAX5090 toc03
VIN (V)
V
OUT
(V)
I
OUT
= 0
I
OUT
= 2A
4.85
4.95
4.90
5.05
5.00
5.10
5.15
6.5 36 4616 26 56 66 76
LINE REGULATION
(MAX5090BATE, V
OUT
= 5V)
MAX5090 toc04
VIN (V)
V
OUT
(V)
I
OUT
= 0
I
OUT
= 2A
I
LOAD
(mA)
V
OUT
(V)
LOAD REGULATION
(MAX5090AATE, V
OUT
= 3.3V)
3.38
3.40
3.32
3.34
3.36
0.1 1 10
100 1000 10,000
MAX5090 toc05
3.28
3.30
3.22
3.24
3.26
3.20
VIN = 76V
VIN = 24V
VIN = 6.5V
I
LOAD
(mA)
V
OUT
(V)
LOAD REGULATION
(MAX5090BATE, V
OUT
= 5V)
5.15
5.10
5.05
5.00
MAX5090 toc06
4.95
4.90
4.85
0.1 1 10
100 1000 10,000
VIN = 24V
VIN = 76V
VIN = 6.5V
0
30
20
10
40
50
60
70
80
90
100
0 800400 1200 1600 2000
EFFICIENCY vs. LOAD CURRENT
(MAX5090AATE, V
OUT
= 3.3V)
MAX5090 toc07
LOAD CURRENT (mA)
EFFICIENCY (%)
VIN = 76V
VIN = 48V
VIN = 24V
VIN = 12V
VIN = 6.5V
0
30
20
10
40
50
60
70
80
90
100
0 800400 1200 1600 2000
EFFICIENCY vs. LOAD CURRENT
(MAX5090BATE, V
OUT
= 5V)
MAX5090 toc08
LOAD CURRENT (mA)
EFFICIENCY (%)
VIN = 6.5V
VIN = 76V
VIN = 48V
VIN = 24V
VIN = 12V
1.0
1.5
2.0
2.5
3.0
3.5
4.0
-50 0-25 25 50 75 100 125 150
OUTPUT CURRENT LIMIT vs. TEMPERATURE
(MAX5090AATE)
MAX5090 toc09
AMBIENT TEMPERATURE (°C)
OUTPUT CURRENT LIMIT (A)
V
OUT
= 3.3V
5% DROP IN V
OUT
PULSED OUTPUT LOAD
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down
DC-DC Converters
_______________________________________________________________________________________ 5
Typical Operating Characteristics (continued)
(VIN= 12V, V
ON/OFF
=12V, TA= TJ= -40°C to +125°C, unless otherwise noted. Typical values are at TA= +25°C. See the Typical
Operating Circuit, if applicable.)
1.0
1.5
2.0
2.5
3.0
3.5
4.0
-50 0-25 25 50 75 100 125 150
OUTPUT CURRENT LIMIT vs. TEMPERATURE
(MAX5090BATE)
MAX5090 toc010
AMBIENT TEMPERATURE (°C)
OUTPUT CURRENT LIMIT (A)
V
OUT
= 5V
5% DROP IN V
OUT
PULSED OUTPUT LOAD
1.0
3.0
2.0
5.0
4.0
6.0
7.0
6.5 36 4616 26 56 66 76
OUTPUT CURRENT LIMIT vs. INPUT VOLTAGE
(MAX5090AATE)
MAX5090 toc11
INPUT VOLTAGE (V)
OUTPUT CURRENT LIMIT (A)
V
OUT
= 3.3V
5% DROP IN V
OUT
PULSED OUTPUT LOAD
1.0
3.0
2.0
5.0
4.0
6.0
7.0
6.5 36 4616 26 56 66 76
OUTPUT CURRENT LIMIT vs. INPUT VOLTAGE
(MAX5090BATE)
MAX5090 toc12
INPUT VOLTAGE (V)
OUTPUT CURRENT LIMIT (A)
V
OUT
= 5V
5% DROP IN V
OUT
PULSED OUTPUT LOAD
300
350
400
450
500
550
600
-50 0-25 25 50 75 100 125 150
NO-LOAD SUPPLY CURRENT vs. TEMPERATURE
(MAX5090AATE)
MAX5090 toc13
AMBIENT TEMPERATURE (°C)
NO-LOAD SUPPLY CURRENT (µA)
V
OUT
= 3.3V
300
400
350
500
450
550
600
6.5 36 4616 26 56 66 76
NO-LOAD SUPPLY CURRENT vs. INPUT VOLTAGE
(MAX5090AATE)
MAX5090 toc14
INPUT VOLTAGE (V)
NO-LOAD SUPPLY CURRENT
V
OUT
= 3.3V
10
14
22
18
26
30
-50 0 25-25 50 100 125 150 175
SHUTDOWN CURRENT vs. TEMPERATURE
(MAX5090AATE)
MAX5090 toc15
AMBIENT TEMPERATURE (°C)
SHUTDOWN CURRENT (µA)
V
OUT
= 3.3V
0
10
5
25
20
15
40
35
30
45
6.5 36 4616 26 56 66 76
SHUTDOWN CURRENT
vs. INPUT VOLTAGE
MAX5090 toc16
INPUT VOLTAGE (V)
SHUTDOWN CURRENT (µA)
V
OUT
= 3.3V
0
3
6
9
11
13
59107861111.5 12 12.5 13
OUTPUT VOLTAGE
vs. INPUT VOLTAGE
MAX5090 toc17
VIN (V)
V
OUT
(V)
I
OUT
= 0A
I
OUT
= 1A
I
OUT
= 2A
MAX5090CATE V
OUT
= 11V
V
ON/OFF
= V
IN
MAX5090 toc18
LOAD-TRANSIENT RESPONSE
(MAX5090AATE)
V
OUT
= 3.3V
A: V
OUT
, 200mV/div, AC-COUPLED
B: I
OUT
, 1A/div, 1A TO 2A
400µs/div
A
B
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters
6 _______________________________________________________________________________________
Typical Operating Characteristics (continued)
(VIN= 12V, V
ON/OFF
=12V, TA= TJ= -40°C to +125°C, unless otherwise noted. Typical values are at TA= +25°C. See the Typical
Operating Circuit, if applicable.)
MAX5090 toc19
LOAD-TRANSIENT RESPONSE
(MAX5090AATE)
V
OUT
= 3.3V
A: V
OUT
, 200mV/div, AC-COUPLED
B: I
OUT
, 500mA/div, 0.1A TO 1A
400µs/div
A
B
LX WAVEFORMS (MAX5090AATE)
MAX5090 toc20
V
OUT
= 3.3V
A
B
A: SWITCH VOLTAGE (LX PIN), 20mV/div (V
IN
= 48V)
B: INDUCTOR CURRENT, 2A/div (I
0
= 2A)
4µs/div
0
MAX5090 toc21
LX WAVEFORMS (MAX5090AATE)
V
OUT
= 3.3V
A: SWITCH VOLTAGE, 20V/div (V
IN
= 48V)
B: INDUCTOR CURRENT, 200mA/div (I
0
= 75mA)
4µs/div
A
B
MAX5090 toc22
LX WAVEFORM
(MAX5090AATE)
V
OUT
= 3.3V
A: SWITCH VOLTAGE, 20V/div (V
IN
= 48V)
B: INDUCTOR CURRENT, 200mA/div (I
OUT
= 0)
4µs/div
A
B
MAX5090 toc23
STARTUP WAVEFORM
(I
OUT
= 0)
A: V
ON/OFF
, 2V/div
B: V
OUT
, 1V/div
4ms/div
A
B
C
SS
= 0.047µF
MAX5090 toc24
STARTUP WAVEFORM
(I
OUT
= 2A)
A: V
ON/OFF
, 2V/div
B: V
OUT
, 1V/div
4ms/div
A
B
C
SS
= 0.047µF
1.0
3.0
2.0
5.0
4.0
6.0
7.0
6.5 36 4616 26 56 66 76
PEAK SWITCH CURRENT
vs. INPUT VOLTAGE
MAX5090 toc25
INPUT VOLTAGE (V)
PEAK SWITCH CURRENT (A)
MAX5090AATE V
OUT
= 3.3V
5% DROP IN V
OUT
PULSED OUTPUT LOAD
MAX5090 toc26
SYNCHRONIZATION
f
SYNC
= 119kHz
SYNC 2V/div
LX 10V/div
2µs/div
MAX5090 toc27
f
SYNC
= 200kHz
SYNCHRONIZATION
1µs/div
SYNC 2V/div
LX 10V/div
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down
DC-DC Converters
_______________________________________________________________________________________ 7
Pin Description
PIN NAME FUNCTION
1, 2 LX Source Connection of Internal High-Side Switch
3 BST Boost Capacitor Connection. Connect a 0.22µF ceramic capacitor from BST to LX.
4VINInput Voltage. Bypass VIN to SGND with a low-ESR capacitor as close to the device as possible.
5VDInternal Regulator Output. Bypass VD to PGND with a 3.3µF/10V or greater ceramic capacitor.
6 SYNC
Synchronization Input. Connect SYNC to an external clock for synchronization. Connect to SGND to select the internal 127kHz switching frequency.
7SS
Soft-Start Capacitor Connection. Connect an external capacitor from SS to SGND to adjust the soft­start time.
8FB
Output Sense Feedback Connection. For fixed output voltage (MAX5090A/MAX5090B), connect FB to V
OUT
.
For adjustable output voltage (MAX5090C), use an external resistive voltage-divider to set V
OUT
. V
FB
regulating set point is 1.228V.
9 ON/OFF
Shutdown Control Input. Pull ON/OFF low to put the device in shutdown mode. Drive ON/OFF high for normal operation. Connect ON/OFF to V
IN
with short leads for always-on operation.
10 SGND Signal Ground. SGND must be connected to PGND for proper operation.
11, 15, 16
N.C. No Connection. Not internally connected.
12 PGND Power Ground
13, 14 DRAIN Internal High-Side Switch Drain Connection
—EP
Exposed Pad. Solder EP to SGND plane to aid in heat dissipation. Do not use as the only electrical ground connection.
Detailed Description
The MAX5090 step-down DC-DC converter operates from a 6.5V to 76V input voltage range. A unique volt­age-mode control scheme with voltage feed-forward and an internal switching DMOS FET provides high effi­ciency over a wide input voltage range. This pulse­width-modulated converter operates at a fixed 127kHz switching frequency or can be synchronized with an external system clock frequency. The device also fea­tures automatic pulse-skipping mode to provide high efficiency at light loads. Under no load, the MAX5090 consumes only 310µA, and in shutdown mode, con­sumes only 20µA. The MAX5090 also features under­voltage-lockout, hiccup-mode output short-circuit protection and thermal shutdown.
ON/
OFF
/Undervoltage Lockout (UVLO)
Use the ON/OFF function to program the external UVLO threshold at the input. Connect a resistive voltage­divider from VINto SGND with the center node to ON/OFF, as shown in Figure 1. Calculate the threshold value by using the following formula:
Set the external V
UVLO(TH)
to greater than 6.45V. The
maximum recommended value for R2 is less than 1MΩ. ON/OFF is a logic input and can be safely driven to the
full VINrange. Connect ON/OFF to VINfor automatic startup. Drive ON/OFF to ground to shut down the MAX5090. Shutdown forces the internal power MOSFET off, turns off all internal circuitry, and reduces the V
IN
supply current to 20µA (typ). The ON/OFF rising thresh­old is 1.546V (max). Before any operation begins, the voltage at ON/OFF must exceed 1.546V. The ON/OFF input has 100mV hysteresis.
If the external UVLO threshold setting divider is not used, an internal undervoltage-lockout feature monitors the supply voltage at VINand allows the operation to start when VINrises above 6.45V (max). The internal UVLO rising threshold is set at 6.17V with 0.5V hystere­sis. The VINand V
ON/OFF
voltages must be above 6.5V
and 1.546V, respectively, for proper operation.
V
R R
x
UVLO TH()
.=+
 
 
1
1 2
138
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters
8 _______________________________________________________________________________________
MAX5090
REGULATOR
(FOR ANALOG)
ENABLE
LX
BST
V
IN
ON/OFF
VREF
REGULATOR
(FOR DRIVER)
OSC RAMP
IREF-PFM
IREF-LIM
CPFM
1.38V
CILIM
FB
EAMP
THERMAL
SHUTDOWN
CPWM
VD
PGND
RAMP
CLK
CONTROL
LOGIC
TYPE 3
COMPENSATION
SGND
x1
*R
H
DRAIN
SYNC
SS
MIN
SRAMP
MUX
SRMP
SCK
*R
L
CLKI RMP
N
HIGH-SIDE
CURRENT SENSE
*RH = 0 AND RL = FOR MAX5090C
Simplified Functional Diagram
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down
DC-DC Converters
_______________________________________________________________________________________ 9
Boost High-Side Gate Drive (BST)
Connect a flying bootstrap capacitor between LX and BST to provide the gate-drive voltage to the high-side n-channel DMOS switch. The capacitor is alternately charged from the internally regulated output-voltage VD and placed across the high-side DMOS driver. Use a
0.22µF, 16V ceramic capacitor located as close to the device as possible.
On startup, an internal low-side switch connects LX to ground and charges the BST capacitor to (VD - V
DIODE
). Once the BST capacitor is charged, the internal low-side switch is turned off and the BST capacitor voltage pro­vides the necessary enhancement voltage to turn on the high-side switch.
Synchronization (SYNC)
SYNC controls the oscillator frequency. Connect SYNC to SGND to select 127kHz operation. Use the SYNC input to synchronize to an external clock. SYNC has a guaranteed frequency range of 119kHz to 200kHz when using an external clock.
When SYNC is connected to SGND, the internal clock is used to generate a ramp with the amplitude in pro­portion to VINand the period corresponding to the internal clock frequency to modulate the duty cycle of the high-side switch.
If an external clock (SYNC clock) is applied at SYNC for four cycles, the MAX5090 selects the SYNC clock. The MAX5090 generates a ramp (SYNC ramp) with the amplitude in proportion to VINand the period corre­sponding to the SYNC clock frequency. The MAX5090 initially blanks the SYNC ramp for 375µs (typ) to allow the ramp to reach its target amplitude (proportion to the VINsupply). After the SYNC blanking time, the SYNC ramp and the SYNC clock switch to the PWM controller and replace the internal ramp and the internal clock, respectively. If the SYNC clock is removed for three internal clock cycles, the internal clock and the internal ramp switch back to the PWM controller.
The minimum pulse-width requirement for the external clock is 350ns, and if the requirement is not met, the MAX5090 could ignore the clock as a noisy bounce.
Soft-Start (SS)
The MAX5090 provides the flexibility to externally pro­gram a suitable soft-start time for a given application. Connect an external capacitor from SS to SGND to use the external soft-start. Soft-start gradually ramps up the reference voltage seen by the error amplifier to control the output’s rate of rise and reduce the input surge cur­rent during startup. For soft-start time longer than 700µs, use the following equation to calculate the soft-start capacitor (CSS) required for the soft-start time (tSS):
where tSS> 700µs and CSSis in Farads.
The MAX5090 also provides an internal soft-start (700µs, typ) with a current source to charge an internal capacitor to rise up to the bandgap reference voltage. The internal soft-start voltage will eventually be pulled up to 3.4V. The internal soft-start reference also feeds to the error amplifier. The error amplifier takes the low­est voltage among SS, the internal soft-start voltage, and the bandgap reference voltage as the input refer­ence for V
OUT
.
Soft-start occurs when power is first applied and when the device exits shutdown. The MAX5090 also goes through soft-start when coming out of thermal-overload protection. During a soft-start, if the voltage at SS (VSS) is charged up to 1.46V in less than 700µs, the MAX5090 takes its default internal soft-start (700µs) to ramp up as its reference. After the SS and the internal soft-start ramp up over the bandgap reference, the error amplifier takes the bandgap reference.
Thermal-Overload Protection
The MAX5090 features integrated thermal-overload protection. Thermal-overload protection limits power dissipation in the device, and protects the device from a thermal overstress. When the die temperature exceeds +175°C, an internal thermal sensor signals the shutdown logic, turning off the internal power MOSFET, resetting the internal soft-start and allowing the IC to cool. The thermal sensor turns the internal power MOSFET back on after the IC’s die temperature cools down to +155°C, resulting in a pulsed output under continuous thermal-overload conditions.
CSS=
××
10 10
146
6
.t
SS
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters
10 ______________________________________________________________________________________
PGND
BST
LX
V
IN
SGND
FB
V
OUT
3.3V, 2A
R1
VD
0.22µF
100µH
3.3µF
R2
ON/OFF
C
OUT
100µF
SS
SYNC
D1 PDS5100H
DRAIN
0.047µF
C
IN
68µF
C
BYPASS
0.47µF
R
IN
10
V
IN
6.5V TO 76V
MAX5090A
Figure 1. Fixed Output-Voltage Configuration
Figure 2. Adjustable Output-Voltage Configuration
V
IN
7.5V TO 76V
R
IN
V
IN
ON/OFF
SYNC
SGND
10
MAX5090C
PGND
DRAIN
LX
BST
FB
SS
VD
0.22µF
3.3µF
100µH
D1 PDS5100H
0.047µF
R
3
R
4
C
IN
C
BYPASS
0.47µF
68µF
V
OUT
5.25V, 2A
C
OUT
100µF
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down
DC-DC Converters
______________________________________________________________________________________ 11
Thermal-overload protection is intended to protect the MAX5090 in the event of a fault condition. For normal circuit operation, do not exceed the absolute maximum junction temperature rating of TJ= +150°C.
Setting the Output Voltage
The MAX5090A/MAX5090B have preset output volt­ages of 3.3V and 5.0V, respectively. Connect FB to V
OUT
for the preset output voltage (Figure 1).
The MAX5090C offers an adjustable output voltage. Set the output voltage with a resistive divider connected from the circuit’s output to ground (Figure 2). Connect the center node of the divider to FB. Choose R4 less than 15k, then calculate R3 as follows:
The MAX5090 features internal compensation for opti­mum closed-loop bandwidth and phase margin. Because of the internal compensation, the output must be sensed immediately after the primary LC.
Inductor Selection
The MAX5090 is a fixed-frequency converter with fixed internal frequency compensation. The internal fixed compensation assumes a 100µH inductor and 100µF output capacitor with 50mESR. It relies on the loca­tion of the double LC pole and the ESR zero frequency for proper closed-loop bandwidth and the phase mar­gin at the closed-loop unity-gain frequency. See Table 2 for proper component values. Usually, the choice of an inductor is guided by the voltage difference between VINand V
OUT
, the required output current and the operating frequency of the circuit. However, use the recommended inductors in Table 2 to ensure stable operation with optimum bandwidth.
Use an inductor with a maximum saturation current rat­ing greater than or equal to the maximum peak current limit (5A). Use inductors with low DC resistance for a higher efficiency converter.
Selecting a Rectifier
The MAX5090 requires an external Schottky rectifier as a freewheeling diode. Connect this rectifier close to the device using short leads and short PC board traces. The rectifier diode must fully conduct the inductor cur­rent when the power FET is off to have a full rectifier function. Choose a rectifier with a continuous current
rating greater than the highest expected output current. Use a rectifier with a voltage rating greater than the maximum expected input voltage, V
IN
. Use a low for­ward-voltage Schottky rectifier for proper operation and high efficiency. Avoid higher than necessary reverse­voltage Schottky rectifiers that have higher forward-volt­age drops. Use a Schottky rectifier with forward-voltage drop (V
F
) less than 0.55V and 0.45V at +25°C and +125°C, respectively, and at maximum load current to avoid forward biasing of the internal parasitic body diode (LX to ground). See Figure 3 for forward-voltage drop vs. temperature of the internal body diode of the MAX5090. Internal parasitic body-diode conduction may cause improper operation, excessive junction tem­perature rise, and thermal shutdown. Use Table 1 to choose the proper rectifier at different input voltages and output current.
Input Bypass Capacitor
The discontinuous input current waveform of the buck converter causes large ripple currents in the input capacitor. The switching frequency, peak inductor cur­rent, and the allowable peak-to-peak voltage ripple reflecting back to the source dictate the capacitance requirement. The MAX5090 high switching frequency allows the use of smaller value input capacitors.
The input ripple is comprised of ∆VQ(caused by the capacitor discharge) and ∆V
ESR
(caused by the ESR of the capacitor). Use low-ESR aluminum electrolytic capacitors with high-ripple current capability at the input. Assuming that the contribution from the ESR and capaci­tor discharge is equal to 90% and 10%, respectively, cal­culate the input capacitance and the ESR required for a specified ripple using the following equations:
R3 =
(.)
.
VxR
OUT
1 228
1 228
4
Table 1. Diode Selection
VIN (V)
DIODE PART
NUMBER
MANUFACTURER
B340LB Diodes Inc.
RB051L-40
Central Semiconductor
6.5 to 36
MBRS340T3 ON Semiconductor
MBRM560 Diodes Inc.
RB095B-60
Central Semiconductor
6.5 to 56
MBRD360T4 ON Semiconductor
50SQ80 IR
6.5 to 76
PDS5100H Diodes Inc.
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters
12 ______________________________________________________________________________________
where:
I
OUT
is the maximum output current of the converter and fSWis the oscillator switching frequency (127kHz). For example, at VIN= 48V, V
OUT
= 3.3V, the ESR and input capacitance are calculated for the input peak-to­peak ripple of 100mV or less, yielding an ESR and capacitance value of 40mand 100µF, respectively.
Low-ESR ceramic multilayer chip capacitors are recom­mended for size-optimized application. For ceramic capacitors assume the contribution from ESR and capaci­tor discharge is equal to 10% and 90%, respectively.
The input capacitor must handle the RMS ripple current without significant rise in the temperature. The maxi­mum capacitor RMS current occurs at approximately 50% duty cycle. Ensure that the ripple specification of the input capacitor exceeds the worst-case capacitor RMS ripple current. Use the following equations to cal­culate the input capacitor RMS current:
where:
I
PRMS
is the input switch RMS current, I
AVGin
is the
input average current, and η is the converter efficiency.
The ESR of the aluminum electrolytic capacitor increas­es significantly at cold temperatures. Use a 1µF or greater value ceramic capacitor in parallel with the alu­minum electrolytic input capacitor, especially for input voltages below 8V.
Output Filter Capacitor
The output capacitor C
OUT
forms double pole with the inductor and a zero with its ESR. The MAX5090’s inter­nal fixed compensation is designed for a 100µF capaci­tor, and the ESR must be from 20mto 100m. The use of an aluminum or tantalum electrolytic capacitor is recommended. See Table 2 to choose an output capacitor for stable operation.
The output ripple is comprised of ∆VOQ(caused by the capacitor discharge), and ∆V
OESR
(caused by the ESR of the capacitor). Use low-ESR tantalum or aluminum electrolytic capacitors at the output. Use the following equations to calculate the contribution of output capac­itance and its ESR on the peak-to-peak output ripple voltage:
The MAX5090 has a programmable soft-start time (t
SS
). The output rise time is directly proportional to the out­put capacitor, output voltage, and the load. The output rise time also depends on the inductor value and the current-limit threshold. It is important to keep the output rise time at startup the same as the soft-start time (tSS) to avoid output overshoot. Large output capacitors take longer than the programmed soft-start time (tSS) and cause error-amplifier saturation. This results in output overshoot. Use greater than 2ms soft-start time for a 100µF output capacitor.
∆∆
VIxESR
V
I
xC x f
OESR L
OQ
L
OUT SW
=≈
8
III x
D
I
VI
Vx
II
I
II
I
D
V
V
PRMS PK DC IPKxI
DC
AVGin
OUT x OUT
IN
PK OUT
L
DC OUT
L
OUT
IN
=+
=
=+
=−
=
+
( )
2
2
3
2
2
η
III
CRMS PRMS AVGin
=−
2
2
I
VV V
Vf L
D
V
V
L
IN OUT OUT
IN SW
OUT
IN
=
−× ××
=
()
ESR
V
I
I
C
IDD
Vf
IN
ESR
OUT
L
IN
OUT
QSW
=
+
 
 
=
×−
×
2
1()
0
100
200
300
400
500
600
700
800
-40 10025 125 150
TEMPERATURE (°C)
V
F_D1
(mV)
Figure 3. Forward-Voltage Drop vs. Temperature of the Internal Body Diode of MAX5090
2A, 76V, High-Efficiency MAXPower Step-Down
DC-DC Converters
______________________________________________________________________________________ 13
MAX5090A/B/C
In a dynamic load application, the allowable deviation of the output voltage during the fast transient load dic­tates the output capacitance value and the ESR. The output capacitors supply the step-load current until the controller responds with a greater duty cycle. The response time (t
RESPONSE
) depends on the closed­loop bandwidth of the converter. The resistive drop across the capacitor ESR and capacitor discharge cause a voltage droop during a step-load. Use a com­bination of low-ESR tantalum and ceramic capacitors for better transient load and ripple/noise performance. Use the following equations to calculate the deviation of output voltage due to the ESR and capacitance value of the output capacitor:
where I
STEP
is the load step and t
RESPONSE
is the response time of the controller. Controller response time is approximately one-third of the reciprocal of the closed-loop unity-gain bandwidth, 20kHz typically.
Board Layout Guidelines
1) Minimize ground noise by connecting the anode of
the Schottky rectifier, the input bypass capacitor ground lead, and the output filter capacitor ground lead to a large PGND plane.
2) Minimize lead lengths to reduce stray capacitance, trace resistance, and radiated noise. In particular, place the Schottky rectifier diode right next to the device. Also, place the BST and VD bypass capaci­tors very close to the device.
3) Connect the exposed pad of the IC to the SGND plane. Do not make a direct connection between the exposed pad plane and SGND (pin 7) under the IC. Connect the exposed pad and pin 7 to the SGND plane separately. Connect the ground connection of the feedback resistive divider, ON/OFF threshold resistive divider, and the soft-start capacitor to the SGND plane. Connect the SGND plane and PGND plane at one point near the input bypass capacitor at VIN.
4) Use large SGND plane as a heatsink for the MAX5090. Use large PGND and LX planes as heatsinks for the rectifier diode and the inductor.
∆∆VIxESR
V
Ixt
C
OESR STEP OUT
OQ
STEP RESPONSE
OUT
=
=
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters
14 ______________________________________________________________________________________
Table 2. Typical External Components Selection (Circuit of Figure 4)
VIN (V)
EXTERNAL COMPONENTS
6.5 to 76 3.3 2
MAX5090AATE C
IN
= 2 x 68µF/100V EEVFK2A680Q, Panasonic
C
BYPASS
= 0.47µF/100V, GRM21BR72A474KA, Murata
C
OUT
= 220µF/6.3V 6SVP220MX, Sanyo
C
BST
= 0.22µF/16V, GRM188R71C224K, Murata
R1 = 0 R2 = Open R
IN
= 10, ±1% (0603)
D1 = PDS5100H, Diodes Inc. L1 = 47µH, DO5022P-473
7.5 to 76 5 2
MAX5090BATE C
IN
= 2 x 68µF/100V EEVFK2A680Q, Panasonic
C
BYPASS
= 0.47µF/100V, GRM21BR72A474KA, Murata
C
OUT
= 100µF/6.3V 6SVP100M, Sanyo
C
BST
= 0.22µF/16V, GRM188R71C224K, Murata
R1 = 0 R2 = Open R
IN
= 10, ±1% (0603)
D1 = PDS5100H, Diodes Inc. L1 = 47µH, DO5022P-473
Application Circuit
PGND
BST
LX
V
IN
V
IN
SGND
FB
V
OUT
R1
VD
L1
C
BST
3.3µF
R2
C
OUT
SS
SYNC
D1
DRAIN
C
SS
C
IN
C
BYPASS
R
IN
MAX5090B
ON/OFF
Figure 4. Fixed Output Voltage
V
OUT
(V) I
OUT
(A)
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down
DC-DC Converters
______________________________________________________________________________________ 15
Table 2. Typical External Components Selection (Circuit of Figure 4) (continued)
VIN (V)
V
OUT
(V)
I
OUT
(A)
EXTERNAL COMPONENTS
6.5 to 40 3.3 2
MAX5090AATE C
IN
= 330µF/50V EEVFK1H331Q, Panasonic
C
BYPASS
= 0.47µF/50V, GRM21BR71H474KA, Murata
C
OUT
= 100µF/6.3V 6SVP100M, Sanyo
C
BST
= 0.22µF/16V, GRM188R71C224K, Murata
R1 = 0 R2 = Open R
IN
= 10, ±1% (0603)
D1 = B360, Diodes Inc. L1 = 100µH, DO5022P-104
7.5 to 40 5 2
MAX5090BATE C
IN
= 330µF/50V EEVFK1H331Q, Panasonic
C
BYPASS
= 0.47µF/50V, GRM21BR71H474KA, Murata
C
OUT
= 100µF/6.3V 6SVP100M, Sanyo
C
BST
= 0.22µF/16V, GRM188R71C224K, Murata
R1 = 0 R2 = Open R
IN
= 10, ±1% (0603)
D1 = B360, Diodes Inc. L1 = 100µH, DO5022P-104
15 to 40 11 2
MAX5090CATE (V
OUT
programmed to 11V)
C
IN
= 330µF/50V EEVFK1H331Q, Panasonic
C
BYPASS
= 0.47µF/50V, GRM21BR71H474KA, Murata
C
OUT
= 100µF/16V 16SVP100M, Sanyo
C
BST
= 0.22µF/16V, GRM188R71C224K, Murata
R1 = 910k R2 = 100k R3 = 88.2k, ±1% (0603) R4 = 10k, ±1% (0603) R
IN
= 10, ±1% (0603)
D1 = B360, Diodes Inc. L1 = 100µH, DO5022P-104
Table 3. Component Suppliers
SUPPLIER WEBSITE
AVX www.avxcorp.com
Coilcraft www.coilcraft.com
Diodes Incorporated www.diodes.com
Panasonic www.panasonic.com
Sanyo www.sanyo.com
TDK www.component.tdk.com
Vishay www.vishay.com
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down DC-DC Converters
16 ______________________________________________________________________________________
Chip Information
PROCESS: BCD
TRANSISTOR COUNT: 7893
PART
TEMP RANGE
PIN­PACKAGE*
OUTPUT
VOLTAGE
(V)
MAX5090CATE+
Adj
MAX5090CATE
Adj
Ordering Information (continued)
*The package code is T1655-3. **EP = Exposed pad. +Denotes lead-free package.
Figure 5. Load-Temperature Monitoring with ON/OFF (Requires Accurate V
IN
)
PGND
BST
LX
V
IN
SGND
FB
V
OUT
5V, 2A
R
t
Ct
VD
C
BST
100µH
3.3µF
C
OUT
100µF
SS
SYNC
D1 B360
DRAIN
*LOCATE PTC AS CLOSE TO HEAT-DISSIPATING COMPONENT AS POSSIBLE.
C
SS
C
IN
68µF
C
BYPASS
R
IN
V
IN
12V
MAX5090B
PTC
ON/OFF
-40°C to +125°C 16 TQFN-EP**
-40°C to +125°C 16 TQFN-EP**
MAX5090A/B/C
2A, 76V, High-Efficiency MAXPower Step-Down
DC-DC Converters
Maxim cannot assume responsibility for use of any circuitry other than circuitry entirely embodied in a Maxim product. No circuit patent licenses are implied. Maxim reserves the right to change the circuitry and specifications without notice at any time.
Maxim Integrated Products, 120 San Gabriel Drive, Sunnyvale, CA 94086 408-737-7600 ____________________ 17
© 2006 Maxim Integrated Products Printed USA is a registered trademark of Maxim Integrated Products, Inc.
Heslington
Package Information
(The package drawing(s) in this data sheet may not reflect the most current specifications. For the latest package outline information go to www.maxim-ic.com/packages
.)
QFN THIN.EPS
D2
(ND-1) X e
e
D
C
PIN # 1 I.D.
(NE-1) X e
E/2
E
0.08 C
0.10 C
A
A1
A3
DETAIL A
E2/2
E2
0.10 M C A B
PIN # 1 I.D.
b
0.35x45°
D/2
D2/2
L
C
L
C
e e
L
CC
L
k
L
L
DETAIL B
L
L1
e
AAAAA
MARKING
I
1
2
21-0140
PACKAGE OUTLINE, 16, 20, 28, 32, 40L THIN QFN, 5x5x0.8mm
-DRAWING NOT TO SCALE-
L
e/2
COMMON DIMENSIONS
MAX.
EXPOSED PAD VARIATIONS
D2
NOM.MIN.
MIN.
E2
NOM. MAX.
NE
ND
PKG. CODES
1. DIMENSIONING & TOLERANCING CONFORM TO ASME Y14.5M-1994.
2. ALL DIMENSIONS ARE IN MILLIMETERS. ANGLES ARE IN DEGREES.
3. N IS THE TOTAL NUMBER OF TERMINALS.
4. THE TERMINAL #1 IDENTIFIER AND TERMINAL NUMBERING CONVENTION SHALL CONFORM TO JESD 95-1 SPP-012. DETAILS OF TERMINAL #1 IDENTIFIER ARE OPTIONAL, BUT MUST BE LOCATED WITHIN THE ZONE INDICATED. THE TERMINAL #1 IDENTIFIER MAY BE EITHER A MOLD OR MARKED FEATURE.
5. DIMENSION b APPLIES TO METALLIZED TERMINAL AND IS MEASURED BETWEEN
0.25 mm AND 0.30 mm FROM TERMINAL TIP.
6. ND AND NE REFER TO THE NUMBER OF TERMINALS ON EACH D AND E SIDE RESPECTIVELY.
7. DEPOPULATION IS POSSIBLE IN A SYMMETRICAL FASHION.
8. COPLANARITY APPLIES TO THE EXPOSED HEAT SINK SLUG AS WELL AS THE TERMINALS.
9. DRAWING CONFORMS TO JEDEC MO220, EXCEPT EXPOSED PAD DIMENSION FOR T2855-3 AND T2855-6.
NOTES:
SYMBOL
PKG.
N
L1
e
E
D
b
A3
A
A1
k
10. WARPAGE SHALL NOT EXCEED 0.10 mm.
JEDEC
0.70 0.800.75
4.90
4.90
0.25
0.250--
4
WHHB
4
16
0.350.30
5.10
5.105.00
0.80 BSC.
5.00
0.05
0.20 REF.
0.02
MIN. MAX.NOM.
16L 5x5
L
0.30 0.500.40
---
---
WHHC
20
5
5
5.00
5.00
0.30
0.55
0.65 BSC.
0.45
0.25
4.90
4.90
0.25
0.65
--
5.10
5.10
0.35
20L 5x5
0.20 REF.
0.75
0.02
NOM.
0
0.70
MIN.
0.05
0.80
MAX.
---
WHHD-1
28
7
7
5.00
5.00
0.25
0.55
0.50 BSC.
0.45
0.25
4.90
4.90
0.20
0.65
--
5.10
5.10
0.30
28L 5x5
0.20 REF.
0.75
0.02
NOM.
0
0.70
MIN.
0.05
0.80
MAX.
---
WHHD-2
32
8
8
5.00
5.00
0.40
0.50 BSC.
0.30
0.25
4.90
4.90
0.50
--
5.10
5.10
32L 5x5
0.20 REF.
0.75
0.02
NOM.
0
0.70
MIN.
0.05
0.80
MAX.
0.20 0.25 0.30
DOWN BONDS ALLOWED
YES3.103.00 3.203.103.00 3.20T2055-3
3.103.00 3.203.103.00 3.20
T2055-4
T2855-3 3.15 3.25 3.35 3.15 3.25 3.35
T2855-6
3.15 3.25 3.35 3.15 3.25 3.35
T2855-4 2.60 2.70 2.80 2.60 2.70 2.80 T2855-5 2.60 2.70 2.80 2.60 2.70 2.80
T2855-7 2.60 2.70
2.80
2.60 2.70 2.80
3.20
3.00 3.10T3255-3 3 3.203.00 3.10
3.203.00 3.10T3255-4 3 3.203.00 3.10
NO
NO NO
NO
YES YES
YES
YES
3.203.00T1655-3 3.10 3.00 3.10 3.20 NO NO3.203.103.003.10T1655N-1 3.00 3.20
3.353.15T2055-5 3.25 3.15 3.25 3.35
YES
3.35
3.15
T2855N-1
3.25 3.15 3.25 3.35
NO
3.353.15T2855-8 3.25 3.15 3.25 3.35
YES
3.203.10T3255N-1 3.00
NO
3.203.103.00
L
0.40
0.40
** ** **
**
** ** ** ** **
** ** **
**
**
SEE COMMON DIMENSIONS TABLE
±0.15
11. MARKING IS FOR PACKAGE ORIENTATION REFERENCE ONLY.
I
2
2
21-0140
PACKAGE OUTLINE, 16, 20, 28, 32, 40L THIN QFN, 5x5x0.8mm
-DRAWING NOT TO SCALE-
12. NUMBER OF LEADS SHOWN ARE FOR REFERENCE ONLY.
3.30T4055-1 3.20 3.40 3.20 3.30 3.40
**
YES
0.050 0.02
0.600.40 0.50
10
-----
0.30
40 10
0.40 0.50
5.10
4.90 5.00
0.25 0.35 0.45
0.40 BSC.
0.15
4.90
0.250.20
5.00 5.10
0.20 REF.
0.70
MIN.
0.75 0.80
NOM.
40L 5x5
MAX.
13. LEAD CENTERLINES TO BE AT TRUE POSITION AS DEFINED BY BASIC DIMENSION "e", ±0.05.
T1655-2
**
YES3.203.103.003.103.00 3.20
T3255-5 YES3.003.103.00
3.20
3.203.10
**
exceptions
Loading...