19-2469; Rev 0; 5/02
MAX1972 Evaluation Kit
General Description
Features
The MAX1972 evaluation kit (EV kit) is a fully assembled
and tested circuit board that evaluates the MAX1970
family of dual step-down regulators. The circuit oper-
ates from an input voltage of 2.6V to 5.5V, and delivers
a minimum of 750mA on each output. The output volt-
ꢀ Current-Mode, 1.4MHz Fixed-Frequency PWM
Operation
ꢀ Dual-Output 180° Out-of-Phase Operation
Reduces Input Ripple Current
ages are programmable from 0.8V to V using external
IN
ꢀ
1ꢀ Output ꢁccuracy Oꢂer ꢃoad, ꢃine, and
Temperature Ranges
feedback resistors, or they can be preset to 3.3V or
1.8V for output 1, and 2.5V or 1.5V for output 2. The
board has a MAX1972 installed, but it can also be used
to evaluate the MAX1970 and the MAX1971. The
MAX1971 features a reset input (RSI), while the
MAX1970/MAX1972 feature a power-fail output (PFO).
ꢀ 750mꢁ Guaranteed Output Current
ꢀ 2.6V to 5.5V Input
ꢀ Power-On Reset Output (POR)
ꢀ Power-Fail Output (MꢁX1970 and MꢁX1972)
ꢀ Power-On Reset Input (MꢁX1971)
Selector Guide
ꢀ Ultra-Compact Design with Small External
Components
POR DELAY
TIME (TYP)
PART
RSI PFO FREQUENCY
ꢀ Outputs ꢁdjustable from 0.8V to V
ꢀ 1.8V/3.3V and 1.5V/2.5V Preset
ꢀ ꢁll Ceramic Capacitor ꢁpplication
ꢀ Soft-Start Reduces Inrush Current
ꢀ Fully ꢁssembled and Tested
IN
MAX1970EEE
MAX1971EEE
MAX1972EEE
16.6ms
175ms
175ms
No
Yes
No
Yes
No
1.4MHz
0.7MHz
1.4MHz
Yes
Ordering Information
Component Suppliers
SUPPLIER
Murata
PHONE
WEBSITE
www6murata6com
www6sumida6com
www6taiyo-yuden6com
PART
TEMP RANGE
IC PACKAGE
ꢃꢃ0-4.ꢁ-1.00
84ꢃ-9Xꢁ-0ꢁꢁꢁ
408-Xꢃ.-41X0
MAX1972EVKIT
-40°C to +85°C
16 QSOP
Sumida
Note: To evaluate the MAX1970 or MAX1971, request free sam-
ples of these parts with the MAX1972EVKIT.
Taiyo-Yuden
Component List
DESIGNATION QTY
DESCRIPTION
DESIGNATION QTY
DESCRIPTION
46ꢃµH ±.0ꢀ% 069A% 80mΩ inductors
Sumida CD5H.D1ꢁ-45ꢃ
10µF ±±0ꢀ% ꢁ6.3 ꢂX5
ceramic capacitor (1±0ꢁ)
L1% L±
±
C1
1
±
±
Taiyo-Yuden JMK.1ꢁBJ10ꢁML
51
5±% 5.
54
1
±
1
±
0
1
1
.
1
10Ω ±Xꢀ resistor (0ꢁ0.)
100kΩ ±Xꢀ resistors (0ꢁ0.)
8±kΩ ±Xꢀ resistor (0ꢁ0.)
0Ω resistors (0ꢁ0.)
061µF ±10ꢀ% 1ꢁ3 ꢂꢃ5
ceramic capacitors (0ꢁ0.)
Taiyo-Yuden EMK10ꢃBJ104KA
C±% C.
C4% Cꢃ
5X% 58
5ꢁ% 59% 510
5ꢃ
Not installed
ꢁ±0pF ±10ꢀ% X03 ꢂꢃ5
ceramic capacitors (0ꢁ0.)
Murata G5M.9ꢂꢃ5ꢁ±1K0X0AD
.9kΩ ±Xꢀ resistor (0ꢁ0.)
MAꢂ19ꢃ±EEE (1ꢁ-pin QSOP)
Shunts
U1
None
None
10µF ±±0ꢀ% 43 ꢂX5
ceramic capacitors (080X)
Taiyo-Yuden AMK±1±BJ10ꢁMG
MAꢂ19ꢃ±E3KIT PC board
CX% Cꢁ
±
.
MAꢂ19ꢃ0/MAꢂ19ꢃ1/MAꢂ19ꢃ±
data sheet
None
1
JU1% JU±% JU.
.-pin headers
________________________________________________________________ Maxim Integrated Products
1
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.