MAX1710 View Datasheet(PDF) - Maxim Integrated
Part Name
Description
Manufacturer
MAX1710 Datasheet PDF : 28 Pages
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High-Speed, Digitally Adjusted
Step-Down Controllers for Notebook CPUs
_____________________________Typical Operating Characteristics (continued)
(7A CPU supply circuit of Figure 1, TA = +25°C, unless otherwise noted.)
OUTPUT OVERLOAD WAVEFORM
LOAD-TRANSIENT RESPONSE
SHUTDOWN WAVEFORM
A
CERAMIC COUT
B
A
A
B
C
C
50µs/div
VOUT = 1.6V
A = VIN, AC-COUPLED, 2V/div
B = VOUT, 0.5V/div
C = INDUCTOR CURRENT, 5A/div
B
D
C
5µs/div
L = 0.7µH, VOUT = 1.6V, VIN = 15V, COUT = 47µF (x4), f = 550kHz
A = VOUT, AC-COUPLED, 100mV/div
B = INDUCTOR CURRENT, 5A/div
C = DL, 5V/div
5µs/div
VIN = 15V, V0 = 1.6V, I0 = 7A
A = VOUT, 0.5V/div
B = INDUCTOR CURRENT, 5A/div
C = SHDN, 2V/div
D = DL, 5V/div
Pin Description
PIN NAME
FUNCTION
1
V+
Battery Voltage Sense Connection. V+ is used only for PWM one-shot timing. DH on-time is inversely propor-
tional to V+ input voltage over a range of 2V to 28V.
2
SHDN
Shutdown Control Input, active low. SHDN cannot withstand the battery voltage. In shutdown mode, DL is
forced to VDD in order to enforce overvoltage protection, even when powered down (unless OVP is high).
3
FB
Fast Feedback Input, normally connected to VOUT. FB is connected to the bulk output filter capacitors local-
ly at the power supply. An external resistor-divider can optionally set the output voltage.
Feedback Remote-Sense Input, normally connected to VOUT directly at the load. FBS internally connects to
4
FBS
the integrator that fine tunes the DC output voltage. Tie FBS to VCC to disable all three integrator amplifiers.
Tie FBS to FB (or disable the integrators) when externally adjusting the output voltage with a resistor-divider.
5
CC
Integrator Capacitor Connection. Connect a 100pF to 1000pF (470pF typical) capacitor to GND to set the
integration time constant.
Current-Limit Threshold Adjustment. Connects to an external resistor to GND. The LX-PGND current-limit
6
ILIM
threshold defaults to +100mV if ILIM is tied to VCC. The current-limit threshold is 1/10 of the voltage forced at
ILIM. In adjustable mode, the threshold is VTH = RLIM ✕ 5µA/10.
7
VCC
Analog Supply Voltage Input for PWM Core, 4.5V to 5.5V. Bypass VCC to GND with a 0.1µF minimum
capacitor.
8
TON
On-Time Selection Control Input. This is a four-level input that sets the K factor to determine DH on-time.
GND = 550kHz, REF = 400kHz, open = 300kHz, VCC = 200kHz.
2.0V Reference Output. Bypass REF to GND with a 0.22µF minimum capacitor. REF can source 50µA for
9
REF
external loads. Loading REF degrades FB accuracy according to the REF load-regulation error
(see Electrical Characteristics).
8 _______________________________________________________________________________________
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